Method for calculating cost coefficient of power grid project construction increase cost in severe cold region

Abstract

The invention discloses a calculation method for a cost taking coefficient of power grid project construction increase cost in a severe cold region. The calculation method comprises the following steps: S1, determining the range of the severe cold region of a power grid technical improvement and maintenance project; analyzing severe cold condition construction influence factors in the severe cold area of the power grid technical improvement and maintenance project; s2, collecting the existing construction data of the implemented power grid technical improvement and maintenance project in the severe cold area of the power grid technical improvement and maintenance project determined in the step S1; the existing construction data is related to the severe cold condition construction influence factors in the step S1; s3, analyzing the construction engineering data in the step S2 to obtain processed average data, and S4, comparing the average data obtained in the step S3 with an existing pricing standard to obtain a required cost taking coefficient of the construction increase cost in the severe cold region. Compared with the prior art, the method can reasonably control the technical improvement and maintenance project cost of the power grid in the severe cold region, and maintains the legitimate rights and interests of all participants.

Description

Technical Field

[0001] The invention belongs to the technical field of power grid project cost, and in particular relates to a method for calculating a charging coefficient of an additional construction fee for a power grid project in a severely cold region. Background Art

[0002] With the development of my country's economy and society, the demand for electricity in remote and cold areas of Northeast and Northwest China has increased rapidly. In order to ease the power supply shortage and promote local economic development, the investment in power grid construction has continued to increase. As a result, the investment in power grid technical transformation and maintenance projects has also increased year by year, achieving full coverage of technical transformation and maintenance areas, balanced project construction and commissioning, and comprehensively strengthening and improving the grid structure of regional power grids, especially those in remote and cold areas.

[0003] At present, the construction and pricing standards for power grid technical transformation and maintenance projects in extremely cold regions adopt the standards of the "Regulations on the Preparation and Calculation of Budgets for Power Grid Technical Transformation and Maintenance Projects" (2015 edition). With the development of social economy and the advancement of power grid technology, the original quota price level can no longer meet the needs of reasonable construction costs and cannot ensure the legitimate rights and interests of all parties involved in the project.

[0004] Therefore, it is necessary to provide a new calculation method for the charging coefficient of the additional fee for power grid project construction in severe cold areas to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to address the deficiencies in the above-mentioned prior art and disclose a method for calculating the charging coefficient of the additional fee for construction of power grid projects in severe cold regions, so as to solve the technical problem that the existing standard price level can no longer meet the needs of reasonable construction costs and cannot ensure the legitimate rights and interests of all parties involved in the project.

[0006] The technical solution adopted by the present invention to solve its technical problem is: the present invention discloses a method for calculating the charging coefficient of the additional fee for construction of power grid projects in severe cold areas, comprising the following steps: S1, determining the scope of the severe cold areas of power grid technical transformation and maintenance projects; analyzing the factors affecting the construction under severe cold conditions in the severe cold areas of the power grid technical transformation and maintenance projects; S2, collecting the existing construction data of the implemented power grid technical transformation and maintenance projects in the severe cold areas of the power grid technical transformation and maintenance projects determined in step S1; the existing construction data is related to the factors affecting the construction under severe cold conditions in step S1; S3, analyzing the construction project data in step S2 to obtain processed average data, and S4, comparing the average data obtained in step S3 with the current pricing standard to obtain the required charging coefficient of the additional fee for construction in severe cold areas.

[0007] In the content of this invention, the current pricing standard is the 2015 version of the power grid technical transformation and maintenance project quota and cost calculation standard.

[0008] Preferably, in step S1, according to the standards and technical measures of the state, industry and various power grid companies for construction under severe cold conditions, the scope of the severe cold area for the power grid technical renovation and maintenance project is determined to be: the area north of 45° north latitude.

[0009] In the content of the present invention, the scope of the severely cold regions of the current power grid technical transformation and maintenance project is within the scope of China.

[0010] Preferably, in step S1, the factors affecting construction under severe cold conditions include: reduced efficiency of labor, reduced efficiency of machinery, increased material consumption and increased cost of measures.

[0011] Preferably, the artificial efficiency reduction includes: the impact of severe cold conditions on human physiological functions and the impact of severe cold conditions on personnel work efficiency; the mechanical efficiency reduction includes: the impact of severe cold on the performance of construction machinery and equipment and the impact of severe cold on the work efficiency of construction machinery and equipment; the increased material consumption includes: the impact of severe cold on material consumption and the impact of severe cold on material unit price; the increase in measures costs includes the impact of increased labor protection supplies, thermal insulation measures and anti-slip measures.

[0012] Preferably, the number of the implemented power grid technical renovation and maintenance projects is at least 10, and the implementing entities of the implemented power grid technical renovation and maintenance projects are at least 2. This is to ensure the extensiveness of the basic data and avoid data deviation.

[0013] Preferably, in step S4, the severe cold region construction includes severe cold region technical transformation project construction, and the severe cold region technical transformation project construction includes: construction projects, installation projects and power transmission line projects.

[0014] Preferably, the existing construction data in step S2 include the measured values ​​of the manual efficiency reduction of typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects, and the internal average method and the arithmetic mean method are used to obtain: the manual efficiency reduction of construction projects, the manual efficiency reduction of substation installation projects, and the manual efficiency reduction of transmission line projects, respectively.

[0015] Preferably, the existing construction data in step S2 also include measured values ​​of mechanical efficiency reduction of typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects, and the internal average method and the arithmetic mean method are used to obtain: mechanical efficiency reduction of construction projects, mechanical efficiency reduction of substation installation projects, and mechanical efficiency reduction of transmission line projects, respectively.

[0016] Preferably, the existing construction data in step S2 also include the measured values ​​of increased material consumption in typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects. A comparative analysis method is adopted, with the measured values ​​of increased material consumption in typical construction processes of construction projects, substation installation projects, and transmission line projects in the technical transformation and maintenance projects as comparative data, and the quota consumable material costs are used as benchmark data. The same unit project is used as the analysis object, and they are consistent and comparable in meeting the same functional requirements, so as to analyze the increase ratio of the quota consumable material costs in severe cold environments, and use the internal average method of returning the data set for data processing to obtain the increase rate of material costs for each professional unit project in severe cold areas; and then the arithmetic mean method is used to calculate and obtain the increase rate of material costs for construction projects, the increase rate of material costs for substation installation projects, and the increase rate of material costs for transmission line projects.

[0017] Preferably, the existing construction data in step S2 also include the measured values ​​of the increase in measures fees for typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects, with the same project as the analysis target and consistency and comparability in meeting the same functional requirements, so as to analyze the increase ratio of measures fees in severe cold environments, and use the internal average method of returning the data set for data sorting, and calculate the increase rate of measures fees for each professional unit project in severe cold areas; then use the arithmetic mean method to calculate and obtain the increase rate of measures fees for construction projects, installation projects, and transmission line projects.

[0018] Compared with the prior art, the present invention can reasonably control the cost of technical transformation and maintenance projects in power grids in severe cold regions, accurately grasp the pricing basis and pricing standards for technical transformation and maintenance projects in power grids in severe cold regions, scientifically and reasonably control investment, standardize the order of the power construction market, improve the comprehensiveness and scientific applicability of quotas, and safeguard the legitimate rights and interests of all participants. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0021] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0022] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0023] The following is combined with Figure 1 The calculation method of the charging coefficient of the additional fee for the construction of power grid projects in severe cold regions of the present invention is further described. In order to clearly describe the scheme of the present invention and ensure the full disclosure of the present invention, the calculation method of the charging coefficient of the additional fee for the construction of power grid projects in severe cold regions of the present invention and the contents related to the present invention are described in multiple parts and from different perspectives.

[0024] Part I: Contents related to the overall situation of the present invention

[0025] 1.1 Main research contents of the present invention

[0026] Based on the existing pricing system and basis for power grid technical transformation and maintenance projects, the additional construction costs in extremely cold areas are demonstrated and calculated, the scope of application is improved, and the adjustment level is unified. This will provide a basis for the preparation of the 2020 version of the "Provisions on the Preparation and Calculation of Budgets for Power Grid Technical Transformation and Maintenance Projects", thereby achieving reasonable determination of project costs and effectively controlling the costs of power grid technical transformation and maintenance.

[0027] The focus is on collecting and investigating the construction status and cost control of technical transformation and maintenance projects of power grids in extremely cold regions. Through project data collection and on-site investigations, we will understand the problems and suggestions in the use of current pricing standards, and at the same time collect data on various expenses actually incurred during the construction process.

[0028] According to the standards and technical measures of the state, industry and power grid companies for construction under severe cold conditions, reasonably determine the scope of severe cold areas, and analyze the impact and measures on construction under severe cold conditions.

[0029] Calculate and analyze to determine the consumption and cost standards of labor, materials, machines, measures, etc. during construction under severe cold conditions, compare and analyze the differences in current pricing standards, and compare and analyze the actual cost expenditures of project construction.

[0030] Determine the coefficient for charging additional construction fees in extremely cold areas, the scope of use and the principles of calculation.

[0031] 1.2 Research methods and principles used in this invention

[0032] (1) Key Factor Analysis

[0033] The analysis is conducted based on the key factors that affect the cost of power grid technical transformation and maintenance projects, namely unit price, consumption and time. On the one hand, the market unit prices of labor and machinery for power grid projects in severe cold areas and conventional areas are analyzed. On the other hand, the actual consumption of labor and machinery in different special intervals of typical construction processes of power grid projects is analyzed.

[0034] (2) Statistical analysis

[0035] 1) Returns the internal mean of a data set

[0036] The internal average method of returning a data set is often used in statistical analysis of similar data. It removes the maximum and minimum values ​​in the data group and reduces the deviation of analysis results caused by inaccurate data in the process of data reporting, collection, and collation. It cannot accurately reflect the true characteristics of the data.

[0037] This method can be used for data statistical analysis with the help of EXCEL. It is simple and practical. It uses the EXCEL function formula to return the internal average of the data set (assuming the data is in column A) = (SUM(A:A)-MAX(A:A)-MIN(A:A)) / (COUNT(A:A)-2).

[0038] It can also be calculated using the mathematical mean method, which is to arrange the data set by size, remove the maximum and minimum values ​​in the data set, and then obtain the average value of the data.

[0039] 2) Statistical test

[0040] After removing outliers, the remaining data set is subjected to statistical tests, the frequency of sample occurrence is counted, the sample probability density function is established, the sample probability density curve is plotted, and the shape of the curve is observed to determine the distribution function of the sample. The mean and variance of the sample data are calculated, and then the reasonable analysis value of the sample data is determined.

[0041] This method is used to process the data collected on the market unit prices of labor and machinery for power grid technical transformation and maintenance projects in severe cold regions and conventional regions, as well as the actual labor and machinery consumption of typical construction procedures.

[0042] (3) Comparative analysis

[0043] On the premise that the statistical caliber is completely consistent, the comparative analysis method is used to analyze the differences and reasons between the actual construction cost and the 2015 version of the standard cost level and the cost level after adjusting the additional construction costs in severe cold areas.

[0044] The comparative analysis method is used to analyze the differences in labor and machinery consumption levels between severe cold areas and conventional areas.

[0045] (4) Timing observation method

[0046] The time observation method, also known as the on-site observation method, is a technical measurement method for studying the consumption of working time. It takes the study of working time consumption as the object and observation and measurement as the means to conduct direct time research through intensive sampling and extensive sampling techniques. The characteristic of the time observation method is that it can link the on-site working time consumption with the technical conditions of construction organization for investigation. On the basis of the classification of construction processes and working time, it uses a set of methods to comprehensively observe, measure, measure, record, organize and analyze the selected process to obtain technically based basic data on the technical organization conditions and working time consumption of the construction process.

[0047] The timing observation method is used to accurately record the actual labor consumption of workers completing tasks in typical projects in severe cold regions, the actual unit consumption of the main machinery used, and related influencing factors, directly obtain first-hand measured data of typical processes, and after scientific research and analysis of the recorded results, compile reliable original data.

[0048] (5) Analogy analysis

[0049] Referring to the relevant adjustment methods and levels for severely cold regions in the "Basis for Construction Project Pricing in Heilongjiang Province" (2019 edition), the "Construction Project Cost Quota in Inner Mongolia Autonomous Region" (2017 edition), and the "Regulations on the Preparation and Calculation of Power Grid Project Construction Budgets" (2018 edition), compare the relevant adjustment methods and levels for technical transformation and maintenance project construction in severely cold regions, and compare with the actual project construction levels.

[0050] (6) Principal component analysis

[0051] Principal component analysis, also known as principal component analysis, aims to use the idea of ​​dimensionality reduction to transform multiple indicators into a few comprehensive indicators (i.e., principal components), where each principal component can reflect most of the information of the original variable, and the information contained is not repeated. This method reduces complex factors to several principal components while introducing multiple variables, simplifies the problem, and the results obtained are more scientific and effective data information. In the study of practical problems, in order to analyze the problem comprehensively and systematically, we must consider many influencing factors. These factors involved are generally called indicators, also known as variables in multivariate statistical analysis. Because each variable reflects certain information of the problem being studied to varying degrees, and there is a certain correlation between the indicators, the information reflected by the statistical data obtained overlaps to a certain extent.

[0052] The principal component analysis method is used to analyze the relevant data collected in the extremely cold regions, and the matrix sample data is analyzed scientifically and rationally to ensure the scientificity and rationality of the adjusted level and the actual level.

[0053] 1.3 Compilation methods and principles of existing quota studies

[0054] (1) Research and funding

[0055] 1) Survey form for additional construction costs of technical renovation and maintenance projects in severe cold regions;

[0056] 2) Settlement statement of technical transformation and maintenance project;

[0057] (2) Quota sub-items sorting

[0058] Based on the on-site investigation of the project, preliminary design documents, technical specifications, installation projects, construction plans and work instructions, construction and acceptance specifications, compare and sort out installation projects, construction projects and other projects to determine whether the quota sub-items need to be adjusted.

[0059] (3) Investigation of construction personnel, materials and equipment consumption and measures costs

[0060] According to the typical construction plan of each quota sub-item, a survey form on construction labor, priced materials, machinery consumption and measures costs under severe cold conditions is prepared to collect basic data.

[0061] (4) Data processing

[0062] According to the survey data and forms, select the processes with a large proportion of manpower, materials and machines to check the specific circumstances of their manpower, materials and machines configuration, confirm the accuracy and validity of the survey form data, and process the manpower, materials and machines consumption according to the quota level calculation principle.

[0063] The quota level calculation principles are as follows:

[0064] ① Unify the measurement units (if there are similar quota sub-items in the 2015 version of the quota, the measurement units of similar quota sub-items shall be adopted; if there are no similar quota sub-items in the 2015 version of the quota, the appropriate measurement units shall be determined according to the actual situation of the project);

[0065] ② The materials filled in should be the materials for pricing. Wrenches, pliers, etc. are tools and should be excluded if they are filled in as materials;

[0066] ③ For small-scale machinery or instruments that do not constitute fixed assets, the machine-shift usage is not included in the machinery, and the related expenses are included in the construction tool and equipment usage fees;

[0067] ④Manual and mechanical work is based on an 8-hour workday;

[0068] ⑤ The consumption of priced materials should be calculated according to the number of turnovers;

[0069] ⑥ Other material costs: Materials with relatively low physical value are reflected in other material costs and are not listed separately.

[0070] (5) Calculation of quota level

[0071] Based on the basic data processing of the labor, material and machine consumption of the quota sub-items, the labor-day unit price, consumable material price and construction machinery shift price are determined according to the construction machinery shift price in the new version of the quota "material and machine library", and the quota level of each quota sub-item is calculated. After the quota compilation is operated in the quota compilation software, the quota can be directly generated.

[0072] (6) Calculation of pre-regulatory fee levels

[0073] Based on settlement documents and other information, the original budget estimates of additional construction fees in extremely cold regions were analyzed, and suggestions for additions, deletions, and modifications were made.

[0074] (7) Comparative analysis of project cost levels

[0075] The quota is calculated together with the estimated charges to form the corresponding project costs, which are compared and analyzed with the bidding, contract or settlement prices to verify and adjust the rationality of the quota price level.

[0076] Part II: Research on the current status of project management of technical transformation and maintenance projects in severe cold regions

[0077] A brief analysis is made on the construction status and cost calculation of technical transformation and maintenance projects under severe cold conditions. The problems reflected in the analysis will be discussed in detail later, and corresponding solutions will be provided.

[0078] 2.1 Overview of the current construction of technical transformation and maintenance projects in severe cold regions

[0079] The Northeast and parts of Northwest my country are located at high latitudes and close to the source of winter winds. They mainly have a temperate monsoon climate, with long and cold winters and short and warm summers. There is a significant temperature difference between the north and the south in winter, with precipitation mostly concentrated in the summer. There is more snowfall in winter, and the snow on the surface stays on the ground for a long time.

[0080] According to the winter construction regulations for construction projects, winter construction begins when the outdoor daily average temperature is stable below 5°C for 5 consecutive days. In winter, the temperature drops, and in many areas the temperature is below 0°C. The moisture contained in the soil, concrete, mortar, etc. freezes, and the construction and installation materials are prone to cracking, which brings many difficulties to the construction. When the average temperature is below 5°C for 5 consecutive days or the daily minimum temperature is below -3°C, winter construction measures must be taken to ensure the quality of the project.

[0081] In extremely cold areas, the winter period generally lasts 3 to 6 months, and the implementation of technical transformation and maintenance projects often affects the normal operation of the power grid. In order to ensure the safe and reliable operation of the power grid, ensure the reliability of power supply, put the project into use as soon as possible, and give full play to its economic and social benefits, technical transformation and maintenance projects of the power grid will also be arranged during the nearly half-year winter period.

[0082] 2.2 Calculation of technical renovation and maintenance project costs under severe cold conditions at present

[0083] At present, the calculation of the additional construction costs of technical transformation and maintenance projects under severe cold conditions adopts the standards of the "Regulations on the Preparation and Calculation of Budgets for Power Grid Technical Transformation and Maintenance Projects" (2015 Edition), and the additional construction costs in the winter rainy season and the construction costs in severe cold areas in the pre-regulatory measures fee are used as the additional construction costs. However, in reality, the additional construction costs in the winter rainy season cannot take special account of the extra-long winter in severe cold areas. The additional construction costs in the winter rainy season only consider the additional costs caused by temperature conditions above -5°C; the additional construction costs in severe cold areas are calculated according to the 15-year construction process standards. With the strengthening of the management of technical transformation and maintenance projects by the state and the industry, and the implementation of new technologies, new processes and new construction strategies, the original additional construction costs in severe cold areas can no longer meet the reasonable pricing requirements; according to the requirements of the winter construction regulations for construction projects, special measures such as material heating, maintenance and insulation are required for construction projects below zero meters under conditions below -5°C, but the existing technical transformation and maintenance quotas do not include the corresponding items, and it is impossible to reasonably determine the project cost.

[0084] Part III: Analysis of research scope in severe cold regions

[0085] Severely cold regions refer to areas where construction costs need to be increased due to special cold conditions. Based on the collected funds, a brief analysis of the current regulations on the classification of severely cold regions in various industries in my country is conducted to define the scope of construction areas in severely cold regions for power grid technical transformation and maintenance projects.

[0086] 3.1 Overview of the scope of severe cold regions defined by meteorology

[0087] In 1918, German climatologist W. ) created a climate classification method based on temperature and precipitation as indicators and referring to the distribution of natural vegetation. It is called the Köppen climate classification in the geological community. This classification has five bioclimatic indicators: the temperature of the hottest month, the temperature of the coldest month, the annual temperature difference, the annual precipitation and the possible evapotranspiration. Based on these indicators, the climate is divided into five categories: tropical climate, arid climate, mild climate, winter cold climate and polar climate. The Köppen climate classification is a typical representative of the empirical climate classification method and is the most widely circulated climate classification scheme in the geological community.

[0088] With the advancement of science and technology, people have discovered that this method is affected by human factors and altitude, which makes the climate division not comprehensive enough.

[0089] In 1956, the Chinese Academy of Sciences published the Draft of China's Climate Zoning on the basis of the research of Chinese scientists, and published the Preliminary Draft of China's Climate Zoning in 1959. In 1958 and 1962, the Central Meteorological Bureau deployed meteorological units in provinces, prefectures and counties to conduct climate resource surveys and climate zoning in their respective areas, and published the China Climate Atlas, making a new national climate zoning.

[0090] This zoning scheme uses the accumulated temperature during the stable period when the daily average temperature is ≥10℃ as the heat index, the dryness (the ratio of evaporation power to precipitation during the same period) as the moisture index, and the accumulated temperature during the stable period when the daily average temperature is ≥10℃ multiplied by 0.16 as the evaporation power. The sunshine data is used as a reference for zoning; based on the heat index, the country is divided into six climate zones, namely, equatorial monsoon climate, tropical monsoon climate, subtropical monsoon climate, warm temperate monsoon climate, temperate monsoon climate, and cold temperate monsoon climate, and one plateau climate zone; based on the two standards of heat and moisture, and with reference to light conditions, the country is divided into eight first-level zones, 32 second-level zones, and 68 third-level zones. According to this zoning scheme, the cold temperate zone is the severe cold area in the usual sense.

[0091] 3.2 Overview of the scope of severe cold regions defined by the construction industry

[0092] According to my country's research on meteorology, the "General Code for Design of Civil Buildings (GB50352-2005)" issued by the Ministry of Construction of the People's Republic of China divides my country into climate zones. The building climate zoning includes 7 main climate zones and 20 sub-climate zones.

[0093] In the Code for Thermal Design of Civil Buildings (GB 50176-2016) issued by the Ministry of Housing and Urban-Rural Development of the People's Republic of China, severe cold areas refer to areas in my country where the average temperature of the coldest month is ≤-10℃ or the number of days with the average daily temperature is ≤5℃ is ≥145 days. It is one of the five climate zones in my country and is mainly distributed in Northeast China, Inner Mongolia Autonomous Region and the northern part of Xinjiang Uygur Autonomous Region, the northern part of Tibet Autonomous Region, Qinghai Province and other provinces and regions. The code makes detailed provisions for the indicators of severe cold areas: Main indicators: The average temperature of the coldest month is between 0 and -10℃ for cold areas; the average temperature of the coldest month is ≤-10℃ for severe cold areas. Auxiliary indicators: When the number of days with the average daily temperature ≤5℃ is between 90 and 145 days per year, it is a cold area; when the number of days with the average daily temperature ≤5℃ is ≥145 days per year, it is a severe cold area.

[0094] The definition of extremely cold areas in the "Handbook of Common Professional Vocabulary in Engineering Construction" published by the Construction Professional Committee of the China Association for Engineering Construction Standardization is an area where the average temperature of the coldest month in the cumulative year and the winter ventilated outdoor calculated temperature are less than or equal to -10℃.

[0095] 3.3 Overview of the scope of severe cold regions defined by the highway industry

[0096] The Method for Compilation of Budget Estimates for Capital Construction Projects of Highway Engineering (JTGB06-2007) issued by the Ministry of Transport of the People's Republic of China stipulates that the division of relevant temperature zones is determined based on temperature data provided by the meteorological department for more than 15 years. The winter period starts from the first day when the outdoor daily average temperature is below 5℃ and the daily minimum temperature is below -3℃ for 5 consecutive days in autumn and winter each year, and ends on the last day when the same temperature appears for 5 consecutive days in spring and summer of the following year. The winter period is defined as the winter zone 1 when the average temperature is above -1℃; the winter zone 2 when the temperature is between -1 and -4℃; the winter zone 3 when the temperature is between -4 and -7℃; the winter zone 4 when the temperature is between -7 and -10℃; the winter zone 5 when the temperature is between -10 and -14℃; and the winter zone 6 when the temperature is below -14℃. The number of consecutive days with average temperature below 0℃ in winter zone 1 is less than 70 days, which is sub-zone Ⅰ, and more than 70 days is sub-zone Ⅱ. The number of consecutive days with average temperature below 0℃ in winter zone 2 is less than 100 days, which is sub-zone Ⅰ, and more than 100 days is sub-zone Ⅱ. The area with temperature higher than winter zone 1, but certain measures must be taken for masonry and concrete engineering construction is quasi-winter zone. The quasi-winter zone is divided into two sub-zones, referred to as quasi-zone 1 and quasi-zone 2. Any area with more than 20 days of daily minimum temperature below 0℃ and less than 15 days of daily average temperature below 0℃ in a year is quasi-zone 1, and more than 15 days is quasi-zone 2.

[0097] 3.4 Overview of the scope of severe cold regions defined by the power industry

[0098] The 2015 edition of the "Regulations on the Preparation and Calculation of Budgets for Power Grid Technical Transformation Projects" and the 2018 edition of the "Regulations on the Preparation and Calculation of Budgets for Power Grid Project Construction" issued by the National Energy Administration divide the temperature zones into areas north of 45° north latitude as high-latitude cold areas, or severe cold areas, which basically conform to the definition of severe cold areas in my country's meteorology.

[0099] 3.5 Definition of the scope of power grid technical transformation and maintenance projects in severe cold regions

[0100] To summarize, the number of days with a daily average temperature of ≤5℃ in the area north of 45° north latitude is ≥145 days per year, which is located in the cold temperate monsoon climate zone defined by meteorology. Considering the continuity of the pricing standards, it is still recommended to define the area north of 45° north latitude as a severely cold area for power grid technical transformation and maintenance projects.

[0101] Part 4: Analysis of the main factors affecting construction in severe cold conditions

[0102] Under severe cold conditions, personnel activities and the operation of mechanical equipment are greatly affected, and their efficiency is reduced; low temperatures have a significant impact on the performance of materials such as steel and plastic concrete; during construction in severe cold weather, attention must be paid to keeping personnel warm, preventing personal accidents, fires, explosions, freezing, poisoning, and traffic accidents.

[0103] 4.1 Artificial efficiency reduction

[0104] 4.1.1 Effects of severe cold conditions on human physiological functions

[0105] Working in severe cold conditions can easily cause a decrease in body or local temperature, resulting in damage to the body. Frostbite can cause a disorder in the internal environment of the person and changes in organ function, leading to serious consequences. In addition to causing damage to the hands and feet, frostbite can also have a certain impact on the body's internal environment system.

[0106] Cells and blood vessels: Frostbite causes changes in endothelial cell function, which in turn changes the coagulation system function, leads to thrombosis, vascular spasm or stenosis, and promotes blood circulation disorders in the frozen tissue. These changes ultimately cause tissue destruction and cell necrosis.

[0107] Central nervous system: Frostbite can cause brain damage. Brain edema is one of the most common and serious secondary injuries of craniocerebral injury. Brain edema after frostbite is mainly vasogenic brain edema, and may also be combined with cytotoxic brain edema. Severe brain edema will lead to irreversible damage to neurons.

[0108] Cardiovascular system: Coldness can directly or indirectly cause skin vasoconstriction, which in turn increases the burden on the heart. In severe cases, it can lead to shock and the risk of inducing angina pectoris. Mild hypothermia can cause tachycardia and peripheral vasoconstriction, which increases cardiac output; moderate hypothermia often causes arrhythmia and progressive bradycardia; severe hypothermia can lead to heart failure.

[0109] Respiratory system: The effects of cold on the respiratory system are multifaceted. Lung damage after frostbite occurs earliest and is the most severe, with pulmonary edema as a notable feature, which can appear 12 hours after injury and gradually worsen. Cold stimulation can also cause pulmonary vein contraction, leading to progressive pulmonary hypertension, and in severe cases, right heart failure. Low temperature can cause incomplete degradation of body substances, and a large amount of incomplete metabolic products accumulate to cause acidosis. At the same time, tissue hypoxia causes brain hypoxia, respiratory depression, insufficient pulmonary ventilation, and respiratory acidosis and metabolic alkalosis. Inhalation of supercooled air can increase respiratory secretions, leading to bronchial mucus secretion and bronchospasm. Inhalation of cold air and cold stimulation of the face and trunk skin can reflexively cause increased airway resistance, which is the main cause of winter exercise asthma. When the body temperature drops to moderate hypothermia, aspiration and pneumonia may occur.

[0110] Liver: Experiments have shown that frostbite causes a significant increase in the toxicity of oxygen free radicals in the liver and kidneys. Oxygen free radical toxicity is one of the important factors that induce many human diseases. Therefore, frostbite seriously damages the liver and kidneys. Deep low-temperature frostbite can cause liver atrophy and fibrosis, bile duct necrosis, stenosis, bile fistula, suppurative cholangitis and other complications. Deep low-temperature frostbite can cause necrosis, stenosis, and even obstruction of the hepatic ducts of the liver lobe.

[0111] Kidneys: Prolonged low temperature can lead to metabolic acidosis, azotemia and acute renal failure, which in turn causes congestion of the glomerular capillaries, degeneration and necrosis of the renal tubules, and potassium excretion disorders in the body. Acute renal failure also reduces the synthesis of vitamin D, affecting the absorption of calcium from the small intestine.

[0112] To summarize, long-term exposure to low temperature environment causes insufficient blood flow to organ tissues, increased tissue hypoxia, and insufficient exchange of nutrients and metabolic products, which can easily cause organ lesions and damage, and lead to multiple organ dysfunction syndrome.

[0113] 4.1.2 Impact of severe cold conditions on personnel work efficiency

[0114] 1. Reduced work efficiency

[0115] People's activities are affected in severe cold environments, their finger flexibility decreases, their speech becomes slurred, their walking speed slows down, their body balance function decreases, their cognitive ability decreases, and their reaction speed slows down, greatly reducing their work efficiency.

[0116] In addition, severe cold conditions will lead to changes in some construction processes and increase labor consumption. For example, to ensure the strength of concrete, materials need to be heated before mixing, and insulation measures need to be taken after pouring; before laying cables, low-temperature cables need to be transferred to an insulation warehouse for heating, and after the cable temperature rises and reaches normal toughness and softness, they are wrapped with quilts and placed in containers with insulation equipment, and transported to the site for laying to ensure that the cables will not be damaged by low temperatures during the laying process; before making and installing cable heads and putting them into boxes, the cables should be evenly heated with a heater before bending operations can be performed.

[0117] 2. Increase rest time

[0118] Construction workers need to warm up for 15 to 20 minutes after working continuously for one hour in a severe cold environment, which greatly shortens the effective working time.

[0119] 3. Inevitable increase in downtime

[0120] In extremely cold regions, some construction processes have also changed, resulting in an inevitable increase in interruption time. For example, when constructing in extremely cold environments, low temperatures increase the difficulty of concrete construction and maintenance and extend the maintenance time; frost on the pole tower makes it impossible to climb the tower, and it is necessary to wait for the frost to thaw before climbing the tower; low temperatures cause changes in steel properties, and before welding steel bars, tests and trial welding must be carried out according to construction conditions, and welding construction can only be carried out after passing the inspection; earthwork backfilling operations should be carried out when the temperature is high from 10:00 to -15:00 to prevent the bottom of the pit from freezing. These changes in processes will increase the waiting time of operators in the same process and reduce manual work efficiency.

[0121] 4.2 Mechanical efficiency reduction

[0122] 4.2.1 Impact of severe cold on the performance of construction machinery and equipment

[0123] 1. Increased failure rate of mechanical equipment

[0124] In severe cold environments, various transmission connectors, bolts, wire ropes, etc. of construction machinery will be affected by low temperatures, resulting in a decrease in strength and rigidity, a decrease in battery capacity, an increase in component wear and tear, and an increase in mechanical failure rates. For example, seals such as hydraulic system connectors will crack and shrink, resulting in poor sealing and leakage; brake mechanism belts will fail due to low temperatures, etc. Therefore, when constructing in severe cold environments, it is necessary to inspect mechanical equipment before construction to prevent work with hidden dangers of failure.

[0125] Impact of fuel and fluid circulation systems on mechanical equipment

[0126] In most parts of my country, No. 20 diesel is sufficient in winter, but in some extremely cold areas in the Northeast and Northwest, No. 35 or higher diesel should be used to prevent the oil from solidifying. For lubricating oil, antifreeze engine oil and antifreeze gear oil should be selected according to the low temperature extremes in extremely cold environments. For the cooling system, antifreeze that meets the local low temperature extremes of the construction site should be selected. For construction machinery with a water cooling system, when it stops running for a long time, in order to prevent the cooling water from freezing, it is necessary to start it at intervals to maintain the machine temperature. After the operation is completed, the water should be drained in time to prevent the cooling water from freezing.

[0127] Increased difficulty in operating mechanical equipment

[0128] When mechanical equipment is hoisted in severe cold conditions, the equipment may freeze to the ground or freeze to each other. The equipment needs to be pried off the ground before lifting to avoid adding unknown lifting loads. Severe cold can easily cause the hook of large machinery to suddenly slip or fail to operate during operation, increasing the difficulty of operation and reducing work efficiency.

[0129] 4.2.2 Impact of severe cold on the working efficiency of construction machinery and equipment

[0130] 1. Reduced work efficiency

[0131] The performance of construction machinery is reduced in severe cold environments. At the same time, in order to prevent slipping and tipping, the transportation and lifting speed of equipment and materials are slowed down.

[0132] Secondly, the lubrication system of the machine itself starts up slowly. In the initial stage of starting up, the machine equipment cannot reach normal operating levels for a long time.

[0133] 2. Reduced utilization coefficient

[0134] In severe cold environments, the working capacity and efficiency of machinery and equipment operators decrease, and the continuous working time is shortened, resulting in a reduction in the operating time of machinery and equipment.

[0135] In severe cold conditions, some mechanical equipment needs to be preheated after starting, and the load can only be loaded when the oil temperature or engine water temperature reaches the standard.

[0136] The number of major overhauls and regular repairs of mechanical equipment increases. Severe cold weather causes increased adhesion and wear between mechanical equipment parts, more accidental accidents, and more maintenance of mechanical equipment. For example, a test shows that when an engine is started at -25℃, the wear of the parts is equivalent to three times the wear when running at normal temperature.

[0137] 4.3 Increased material consumption

[0138] 4.3.1 Impact of severe cold on material consumption

[0139] 1. Increased material processing loss

[0140] Under severe cold conditions, material properties are greatly reduced, resulting in increased material processing losses. For example, the toughness of steel and plastic materials decreases at low temperatures, resulting in an increase in processing scrap rates.

[0141] 2. Increased material construction loss

[0142] In severe cold conditions, human functions are affected, and sensitivity is reduced, resulting in increased material construction losses. For example, wearing heavy thermal gloves when tightening bolts in tower assembly can cause the bolts and nuts to be lost due to unstable grip, resulting in increased construction losses; at the same time, the performance of materials is reduced, resulting in increased material breakage rate. For example, signboards and ribbons will become brittle at low temperatures, and are easily damaged during unpacking inspection and installation, resulting in increased material losses.

[0143] 3. Increased material transportation losses

[0144] In severe cold conditions, materials will suffer increased losses during storage, delivery, and transportation due to human operation or reduced low-temperature performance of materials. For example, when glass insulators are unloaded or stacked on site, they become brittle due to low temperatures, increasing the breakage rate.

[0145] 4.3.2 Impact of severe cold on material unit prices

[0146] Under severe cold conditions, the costs of material processing and transportation increase accordingly, causing the unit price of materials to rise. For example, the winter heating expenses of material factories in severe cold regions and the increased difficulty in mining sand, stone and other ground materials all increase the production costs of materials and cause the unit price of materials to rise.

[0147] 4.4 Increase in measures fees

[0148] 1. Labor protection products

[0149] In the cold winter season, in order to prevent frostbite, employees are provided with essential winter clothing, including warm clothes, non-slip warm boots, thermal waterproof gloves, cotton safety helmets and other personal labor protection supplies for winter construction. According to local actual conditions and different types of work, employees are provided with vests, knee pads, waist protectors, etc.

[0150] 2. Insulation measures

[0151] Prepare a warm room at the construction site so that construction workers can enter regularly to keep warm, to prevent colds and frostbite. Provide boiled water and food in the warm room to replenish energy for employees in time. Construction workers should keep warm when working for one hour in a cold environment.

[0152] Concrete curing requires the construction of an insulation shed, using charcoal heating or electric heating to ensure that the standard curing temperature conditions of concrete are met. For cast-in-place concrete, materials such as sand, stone, and water also need to be heated, generally through frying, steam, boilers, etc.

[0153] Take warming measures for mechanical equipment, such as: equipping with on-board fuel steam boilers to preheat large construction machinery with high-temperature steam; setting up insulated warehouses at the construction site to store construction machinery and equipment materials; covering medium-sized equipment such as welding machines, generator sets, and batteries with insulation layers; placing small equipment such as GPS and total stations in the cab of the oil heater or in a heat preservation shed before trial use, and putting them back immediately after use; starting the parking heating system for machinery and vehicles at night.

[0154] As the temperature drops, the mechanical properties of equipment components will also decline to varying degrees, making them more susceptible to damage. Therefore, measures must be taken and controls strengthened at all stages during storage, transportation, and installation to ensure that the equipment is intact.

[0155] 3. Anti-slip measures

[0156] Motor vehicles should be equipped with anti-skid tires or tire anti-skid chains for cold regions. After heavy snow, the exposed parts of construction machinery, stairs, and operating platforms should be cleared of snow; when stacking materials, anti-skid measures must be taken to prevent components from slipping and injuring people; workers working at high altitudes such as towers must take reliable anti-skid safety protection measures.

[0157] Part V: Calculation and Analysis of the Standards for Charging Additional Construction Fees in Severely Cold Regions

[0158] 5.1 Analysis of the additional costs of technical transformation projects in severe cold regions

[0159] 5.1.1 Analysis of Increased Labor and Machinery Costs

[0160] 1. Artificial efficiency reduction

[0161] The main construction processes of construction engineering, substation installation engineering, and transmission line engineering in technical transformation and maintenance projects were selected for actual measurement (data provided by 15 research units), and compared with manual efficiency reduction, the internal average method of returning the data set was adopted. With the help of EXCEL function formula, the internal average of the data set was returned (assuming that the data is in column A).

[0162] =(SUM(A:A)-MAX(A:A)-MIN(A:A)) / (COUNT(A:A)-2), the basic value of labor efficiency reduction in each construction process is calculated, and the statistical analysis data is shown in Appendix 1.

[0163] Through calculation, the labor efficiency reduction of typical processes of various professional unit projects in severe cold regions is shown in Table 5-1-1.

[0164] Table 5-1-1 Summary of labor efficiency reduction in typical construction processes in severe cold regions

[0165] Serial number Typical process Artificial efficiency reduction 1 Manual construction of earthwork excavation 11％ 2 Earthwork excavation machinery construction 10％ 3 Foundation pouring 12％ 4 Concrete pouring of walls, beams, slabs, columns, etc. 12％ 5 Masonry wall 12％ 6 Metal structural engineering railings, platforms, steel roofs, etc. 12％ 7 Structure support, lightning rod, etc. 12％ 8 Transformer installation 11％ 9 Circuit breaker installation 11％ 10 Disconnector 12％ 11 Insulator string installation 10％ 12 Lightning arrester installation 10％ 13 Capacitor installation 11％ 14 Flexible busbar installation 10％ 15 Rectangular busbar installation 11％ 16 Tower foundation pit excavation 12％ 17 Tower assembly 11％ 18 Wire laying 6％ 19 Insulator string installation 11％

[0166] As shown in the table above, it can be concluded that the labor efficiency of each typical process in construction projects in severe cold regions is reduced by 10% to 12%, the labor efficiency of each typical process in installation projects is reduced by 10% to 12%, and the labor efficiency of each typical process in transmission line projects is reduced by 6% to 12%.

[0167] The quota price level of power grid technical transformation and maintenance projects is obtained through comprehensive calculation based on the average social productivity level. Therefore, the labor efficiency reduction of each professional unit project in severe cold regions can be calculated using the arithmetic mean method of the labor efficiency reduction of each typical process. Through calculation, the labor efficiency reduction of each professional unit project can be obtained, as shown in Table 5-1-2.

[0168] Table 5-1-2 Artificial efficiency reduction of technical transformation projects in severe cold regions

[0169] Unit Project Construction Engineering Installation Engineering Transmission line engineering Artificial efficiency reduction 11.52％ 10.81％ 9.90％

[0170] 2. Mechanical efficiency reduction

[0171] The main typical construction processes of building projects, substation installation projects and transmission line projects in technical transformation and maintenance projects were selected for actual measurement (data were provided by 15 research units), and the mechanical efficiency reduction was compared. The internal average method of returning the data set was adopted. With the help of the EXCEL function formula, the internal average of the data set was returned (assuming the data is in column A) = (SUM(A:A)-MAX(A:A)-MIN(A:A)) / (COUNT(A:A)-2), the basic values ​​of mechanical efficiency reduction in each construction process were calculated. The statistical analysis data are shown in Appendix 2.

[0172] Through calculation, the mechanical efficiency reduction of typical processes of various professional unit projects in severe cold regions is shown in Table 5-1-3.

[0173] Table 5-1-3 Summary of reduced efficiency of construction machinery in typical processes in severe cold regions

[0174] Serial number Typical process Mechanical efficiency reduction 1 Manual construction of earthwork excavation 9％ 2 Earthwork excavation machinery construction 11％ 3 Foundation pouring 11％ 4 Concrete pouring of walls, beams, slabs, columns, etc. 12％ 5 Masonry wall 10％ 6 Metal structural engineering railings, platforms, steel roofs, etc. 11％ 7 Structure support, lightning rod, etc. 11％ 8 Transformer installation 11％ 9 Circuit breaker installation 10％ 10 Disconnector 11％ 11 Insulator string installation 10％ 12 Lightning arrester installation 10％ 13 Capacitor installation 11％ 14 Flexible busbar installation 10％ 15 Rectangular busbar installation 10％ 16 Tower foundation pit excavation 11％ 17 Tower assembly 11％ 18 Wire laying 7％ 19 Insulator string installation 10％

[0175] As shown in the table above, it can be concluded that the mechanical efficiency reduction of each typical process of construction projects in severe cold regions is 9% to 12%, the mechanical efficiency reduction of each typical process of installation projects is 10% to 11%, and the mechanical efficiency reduction of each typical process of transmission line projects is 7% to 11%.

[0176] At the same time, the standard price level of power grid technical transformation and maintenance projects is obtained by comprehensive calculation of the social average productivity level. Therefore, the efficiency reduction of engineering machinery of various professional units in severely cold areas is calculated using the arithmetic mean method of the efficiency reduction of machinery in each typical process. Based on the calculation, the efficiency reduction of engineering machinery of various professional units in severely cold areas is obtained, as shown in Table 5-1-4.

[0177] Table 5-1-4 Efficiency reduction of engineering machinery in severe cold regions after technical transformation

[0178] Unit Project Construction Engineering Installation Engineering Transmission line engineering Mechanical efficiency reduction 10.54％ 10.50％ 9.99％

[0179] 5.1.2 Analysis of increased material costs

[0180] The actual measurements of major typical projects such as construction projects, substation installation projects, and transmission line projects in the technical transformation and maintenance projects were selected (the data were provided by 15 survey units). Based on the pricing basis of power grid technical transformation and maintenance projects and combined with the actual project construction, the comparative analysis method was adopted. The measured consumable material costs were used as comparison data, and the quota consumable material costs were used as benchmark data. The same unit project was used as the analysis object, which was consistent and comparable in meeting the same functional requirements. The increase ratio of the quota consumable material costs in severe cold environments was analyzed, and the internal average method of returning to the data set was used for data sorting. The statistical analysis data are shown in Appendix 3.

[0181] Through calculation, the increase rate of engineering material costs for each professional unit in extremely cold regions is shown in Table 5-1-5.

[0182] Table 5-1-5 Summary of the increase rate of consumable material costs for professional unit projects in severe cold regions

[0183] Serial number Professional unit engineering Increase rate of consumer material cost 1 Construction Engineering 35 kV 0.74％ 2 Construction Engineering 66 kV 0.77％ 3 Construction Engineering 110 kV 0.80％ 4 Construction Engineering 220 kV 0.83％ 5 Installation Project 35 kV 9.41％ 6 Installation Project 66 kV 9.31％ 7 Installation project 110 kV 9.36％ 8 Installation project 220 kV 9.70％ 9 Transmission Line Project 35 kV 43.23％ 10 Transmission Line Project 66 kV 44.52％ 11 Transmission Line Project 110 kV 43.92％ 12 Transmission Line Project 220 kV 38.07％

[0184] As shown in the above table, it can be concluded that the increase rate of consumable material costs for construction projects in severe cold regions is 0.74% to 0.83%, the increase rate of consumable material costs for installation projects is 9.31% to 9.70%, and the increase rate of consumable material costs for transmission line projects is 38.07% to 44.52%.

[0185] The increase rate of consumable material costs for each professional unit project in severe cold regions was calculated using the arithmetic mean method, as shown in Table 5-1-6.

[0186] Table 5-1-6 Increase rate of material cost for each professional project

[0187] Unit Project Construction Engineering Installation Engineering Transmission line engineering Increase rate of consumer material cost 0.79％ 9.45％ 42.43％

[0188] 5.1.3 Analysis of increased cost of measures

[0189] The actual measurement of major typical projects such as construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects was selected (data provided by 15 research units). Based on the pricing basis of power grid technical transformation and maintenance projects, the increase in project measures fees for professional units of various voltage levels under severe cold environments was collected. The same project was taken as the analysis target, and it was consistent and comparable in meeting the same functional requirements. The increase proportion of measures fees under severe cold environments was analyzed, and the internal average method of returning to the data set was used for data sorting. The statistical analysis data are shown in Appendix 4.

[0190] Through calculation, the cost increase rate of engineering measures for each professional unit in severe cold regions is shown in Table 5-1-7.

[0191] Table 5-1-7 List of increase rates of engineering measures fees for professional units in severe cold regions

[0192] Serial number Professional unit engineering Increase rate of measures cost 1 Construction Engineering 35 kV 14.74％ 2 Construction Engineering 66 kV 18.17％ 3 Construction Engineering 110 kV 18.29％ 4 Construction Engineering 220 kV 18.71％ 5 Installation Project 35 kV 14.75％ 6 Installation Project 66 kV 15.31％ 7 Installation project 110 kV 15.35％ 8 Installation project 220 kV 15.94％ 9 Transmission Line Project 35 kV 16.27％ 10 Transmission Line Project 66 kV 16.94％ 11 Transmission Line Project 110 kV 17.04％ 12 Transmission Line Project 220 kV 17.91％

[0193] As shown in the above table, it can be concluded that the increase rate of construction project measures in severe cold regions is 14.74% to 18.71%, the increase rate of installation project measures is 14.75% to 15.94%, and the increase rate of transmission line project measures is 16.27% to 17.91%.

[0194] The increase rate of engineering measures fees for each professional unit in severe cold regions was calculated using the arithmetic mean method, as shown in Table 5-1-8.

[0195] Table 5-1-8 Increase rate of professional engineering measures fee

[0196] Unit Project Construction Engineering Installation Engineering Transmission line engineering Increase rate of measures cost 17.48％ 15.34％ 17.04％

[0197] 5.1.4 Summary of analysis on additional construction costs in severe cold regions

[0198] This chapter takes the technical renovation and maintenance projects in severe cold regions as the research object, mainly discusses the four aspects of labor efficiency reduction, machinery efficiency reduction, material increase and measure fee increase, and analyzes the difference and degree of difference from the quota level in conventional regions. Among them, the labor cost reduction efficiency is based on the quota labor cost, the machinery cost reduction efficiency is based on the quota machinery cost, the material cost growth rate is based on the quota consumable material cost, and the measure fee growth rate is calculated based on the quota measure fee.

[0199] Through the calculations and analysis in this chapter, the growth rate of the cost of technical transformation and maintenance projects for power grids in severely cold regions is shown in Table 5-1-9 below.

[0200] Table 5-1-9 Growth rate of technical renovation and maintenance project costs of power grids in severe cold regions

[0201] Cost Type Substation construction project Substation installation project Transmission line engineering Labor cost 11.52％ 10.81％ 9.90％ Machinery Fee 10.54％ 10.50％ 9.99％ Additional material costs 0.79％ 9.45％ 42.43％ Increase in measures costs 17.48％ 15.34％ 17.04％

[0202] 5.2 Analysis of the rate of additional construction costs for technical transformation projects in severe cold regions

[0203] 5.2.1 Analysis ideas

[0204] 1. The following principles should be followed in the analysis of the construction surcharge rate in severe cold regions:

[0205] (1) Comply with national laws, regulations, rules, ordinances, methods and documents.

[0206] (2) Based on the 2015 edition of the quota and cost calculation standards for power grid technical transformation and maintenance projects.

[0207] (3) The actual cost of the project shall be used as the main calculation value and as the basis for adjusting the costs in specific cold regions.

[0208] 2. The analysis of the rate of construction surcharge in severe cold regions mainly follows the following points:

[0209] (1) Determine the fee base

[0210] Taking into account the differences in engineering process content and combined with the setting of the charging base in the "Regulations on the Preparation and Calculation of Construction Budgets for Power Grid Technical Transformation and Maintenance Projects" (2015 edition), labor is most easily affected by the severe cold environment during the construction process, and the efficiency reduction is more obvious. Therefore, the technical transformation and maintenance projects still use the 2015 version of the budget regulations and use labor costs as the charging base.

[0211] (2) Calculate the comprehensive rate of construction cost increase

[0212] The above article analyzes the cost of four types of influencing factors in severe cold regions. However, in actual projects, there are certain differences in the degree of influence of different influencing factors on the increase in construction costs in severe cold regions. Simple arithmetic summation cannot reflect the increase in costs of various influencing factors during the actual construction process. Therefore, the report uses weights to represent the relative degree of influence between various factors, so as to obtain a comprehensive adjustment coefficient based on labor costs. Suppose the comprehensive adjustment coefficient is K, the adjustment coefficients for labor efficiency reduction, mechanical efficiency reduction, material increase, and measures cost are k1, k2, k3, and k4 respectively, and the weights of each influencing factor are ω1, ω2, ω3, and ω4 respectively, then the comprehensive adjustment coefficient is:

[0213] K=ω1k1+ω2k2+ω3k3+ω4k4

[0214] 5.2.2 Analysis model

[0215] In summary, the key to calculating the comprehensive rate is to determine the weights of each influencing factor. The principal component analysis method has the advantages of easy operation and simple data requirements in determining weights, so we choose the principal component analysis method to calculate and analyze the weights.

[0216] 1. The basic idea of ​​principal component analysis

[0217] In the study of empirical problems, in order to analyze the problems comprehensively and systematically, we must consider many influencing factors. These factors involved are generally called indicators, also known as variables in multivariate statistical analysis. Because each variable reflects certain information of the problem being studied to varying degrees, and there is a certain correlation between the indicators, the information reflected by the statistical data obtained overlaps to a certain extent. When using statistical methods to study multivariate problems, too many variables will increase the amount of calculation and the complexity of the analysis problem. People hope that in the process of quantitative analysis, fewer variables are involved and more information is obtained. Principal component analysis was created to meet this requirement and is an ideal tool for solving such problems.

[0218] Principal component analysis is a statistical method for dimensionality reduction. It uses an orthogonal transformation to transform the original random vector whose components are correlated into a new random vector whose components are uncorrelated. This is expressed algebraically as transforming the covariance matrix of the original random vector into a diagonal matrix, and geometrically as transforming the original coordinate system into a new orthogonal coordinate system so that it points to the p orthogonal directions with the largest sample point distribution. The multidimensional variable system is then subjected to dimensionality reduction processing so that it can be converted into a low-dimensional variable system with a higher accuracy. The low-dimensional system is further converted into a one-dimensional system by constructing an appropriate value function.

[0219] 2. Principles of principal component analysis

[0220] Principal component analysis is a statistical method that tries to regroup the original variables into a new set of several independent comprehensive variables, and at the same time, according to actual needs, several fewer sum variables can be extracted from them to reflect as much information as possible from the original variables. It is also a method of mathematically dealing with dimensionality reduction. Principal component analysis is a method of trying to regroup the original many related indicators (such as P indicators) into a new set of independent comprehensive indicators to replace the original indicators. Usually, the mathematical treatment is to linearly combine the original P indicators as a new comprehensive indicator.

[0221] 3. The role of principal component analysis

[0222] (1) Principal component analysis can reduce the dimensionality of the data space being studied. That is, the m-dimensional Y space is used to replace the p-dimensional X space (m<p), and the low-dimensional Y space replaces the high-dimensional x space with little information loss. That is, when there is only one principal component Y1 (i.e. m=1), this Y1 is still obtained using all X variables (p). For example, to calculate the mean of Y1, the mean of all x must be used. Among the first m principal components selected, if a certain X i If all coefficients of X are close to zero, we can i Deletion is also a way to delete redundant variables.

[0223] (2) Sometimes the factor loading a ij conclusions and clarify some relationships between X variables.

[0224] (3) A graphical representation method for multidimensional data. We know that when the dimension is greater than 3, geometric figures cannot be drawn. Most of the problems studied in multivariate statistics involve more than 3 variables. It is impossible to represent the research problem graphically. However, after principal component analysis, we can select the first two principal components or two of them, and draw the distribution of n samples on a two-dimensional plane based on the scores of the principal components. The graph can intuitively show the position of each sample in the principal component, and then the samples can be classified and processed. The graph can be used to find outliers far away from most sample points.

[0225] (4) Construct a regression model using principal component analysis. That is, use each principal component as a new independent variable to replace the original independent variable x for regression analysis.

[0226] (5) Use principal component analysis to screen regression variables. The selection of regression variables has important practical significance. In order to make the model itself easier to perform structural analysis, control and prediction, it is best to select the best variables from the subset of original variables to form the best variable set. Using principal component analysis to screen variables can select variables with less computational effort and achieve the effect of selecting the best variable subset.

[0227] 4. Establishment of principal component analysis model

[0228] (1) Standardized collection of original indicator data p-dimensional random vector X = (x1, x2...x p ) n samples X in T i =(x i1 ,x i2 ......x ip )T, i=1,2...n.

[0229] n>p, construct a sample array, and perform the following standardized transformation on the sample array elements: in Get the standardized matrix Z.

[0230] (2) Calculate the correlation coefficient matrix for the standardized matrix Z

[0231] in,

[0232] (3) Solve the characteristic equation of the sample correlation matrix R |R-λI p |=0 to obtain p characteristic roots and determine the principal components.

[0233] according to Determine the value of m so that the information utilization rate reaches more than 85%. j , j=1,2...m, solve the equation system R b =λj b The unit eigenvector

[0234] (4) Convert the standardized indicator variables into principal components

[0235]

[0236] U1 is called the first principal component, U2 is called the second principal component, ..., U p It is called the pth principal component.

[0237] (5) Comprehensive evaluation of m principal components

[0238] The final evaluation value is obtained by weighted summing of the m principal components, where the weight is the variance contribution rate of each principal component.

[0239] 5. Advantages of principal component analysis

[0240] (1) It can eliminate the correlation between evaluation indicators. This is because the principal component analysis method forms independent principal components after transforming the original data indicator variables, and practice has shown that the higher the correlation between indicators, the better the principal component analysis effect.

[0241] (2) It can reduce the workload of indicator selection. For other evaluation methods, it is difficult to eliminate the correlation between evaluation indicators, so it takes a lot of effort to select indicators. However, since principal component analysis can eliminate this correlation, it is relatively easier to select indicators.

[0242] (3) In principal component analysis, the principal components are arranged in order according to the size of the variance. When analyzing a problem, some principal components can be discarded and only the first few principal components with larger variances can be used to represent the original variable, thereby reducing the computational workload. When using principal component analysis for comprehensive evaluation, the principle of selection is that the cumulative contribution rate is ≥ 85%, so that the evaluation results will not be affected by saving workload but missing key indicators.

[0243] 5.2.3 Calculation of the rate of additional construction costs in severe cold regions

[0244] This section selects 53 typical projects of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects (data provided by 15 research units), and brings the relative efficiency reduction ratio coefficient calculated in Chapter 5.1 into the 53 projects to calculate the efficiency reduction amount. The efficiency reduction amount is then used to calculate the proportion of professional unit projects such as construction, installation, and lines, as shown in the engineering cost analysis table. At the same time, SPSS is used to analyze the proportion of labor efficiency reduction, mechanical efficiency reduction, material increase, and measure cost increase in the 53 projects to the engineering cost, and the weight coefficient is obtained. The calculation results of each unit project are as follows:

[0245] 1. Construction project costs

[0246] Through the analysis and collation of the surveyed project data, the adjustment ratios of construction project costs due to various influencing factors in severely cold regions were obtained, as shown in Table 5-2-1.

[0247] Table 5-2-1 Analysis of construction project costs in severe cold regions

[0248]

[0249] Through SPSS software analysis, the weights of the four factors were normalized and the effective weights ω1, ω2, ω3, and ω4 were 0.4855, 0.2652, 0.1665, and 0.0828, respectively.

[0250] Taking labor costs as the charging base, we calculated the proportion of machinery costs, material costs and measures costs in the above-mentioned projects to labor costs respectively, and obtained that the increase coefficients of the four types of influencing factors relative to labor costs under the same caliber were k1, k2, k3, and k4, which were 6.69%, 6.43%, 2.96%, and 19.26% respectively.

[0251] Combining the weight and the increase coefficient, the additional construction fee rate for construction projects in severe cold areas is: K = ω1k1 + ω2k2 + ω3k3 + ω4k4 = 0.4855*6.69% + 0.2652*6.43% + 0.1665*2.96% + 0.0828*19.26% = 7.04%.

[0252] 2. Installation engineering fee

[0253] Through the analysis and collation of the surveyed project data, the adjustment ratios of installation project costs due to various influencing factors in severely cold regions were obtained, as shown in Table 5-2-2.

[0254] Table 5-2-2 Analysis of installation engineering costs in severe cold regions Through SPSS software analysis, the weights of the four factors were normalized and the effective weights ω1, ω2, ω3, and ω4 were 0.5283, 0.2719, 0.1314, and 0.0684, respectively.

[0255] Taking labor costs as the charging base, we calculated the proportion of machinery costs, material costs and measures costs in the above-mentioned projects to labor costs respectively, and obtained that the increase coefficients of the four types of influencing factors relative to labor costs under the same caliber were k1, k2, k3, and k4, which were 9.71%, 9.50%, 9.45%, and 10.24% respectively.

[0256] Combining the weight and the increase coefficient, the additional fee rate for installation projects in severe cold regions is:

[0257] K=ω1k1+ω2k2+ω3k3+ω4k4=0.5283*9.71%+0.2719*9.50%+0.1314*9.45%+0.0684*10.2

[0258] 4% = 9.65%

[0259] 3. Transmission line engineering

[0260] Through the analysis and collation of the surveyed project data, the adjustment ratios of the transmission line project costs due to various influencing factors in severely cold regions were obtained, as shown in Table 5-2-3.

[0261] Table 5-2-3 Analysis of additional costs for line construction in severe cold regions

[0262]

[0263] Through SPSS software analysis, the weights of the four factors were normalized and the effective weights ω1, ω2, ω3, and ω4 were 0.4869, 0.2427, 0.1305, and 0.1399, respectively.

[0264] Taking labor costs as the charging base, we calculated the proportion of machinery costs, material costs and measures costs in the above-mentioned projects to labor costs respectively, and obtained that the increase coefficients of the four types of influencing factors relative to labor costs under the same caliber were k1, k2, k3, and k4, which were 9.90%, 9.99%, 12.43%, and 10.04% respectively.

[0265] Combining the weight and the increase coefficient, the additional fee rate for construction in cold regions of the line project is:

[0266] K=ω1k1+ω2k2+ω3k3+ω4k4=0.4869*9.90%+0.2427*9.99%+0.1305*12.43%+0.1399*10.

[0267] 04% = 10.27%

[0268] 5.2.4 Summary of analysis on construction surcharge rates in severe cold regions

[0269] This chapter sorts out and analyzes the original data of power grid technical transformation and maintenance projects in severe cold regions, determines that the four influencing factors of labor efficiency reduction, mechanical efficiency reduction, material increase and measure fees are the basis for analysis, and analyzes the adjustment coefficient in the form of weight calculation using the principal component analysis model. It is finally determined that the construction fee increase rate for construction projects, installation projects, and transmission line projects in severe cold regions is based on labor costs. The comprehensive rate is calculated as shown in Table 5-2-4.

[0270] Table 5-2-4 Rates of additional construction fees for technical transformation projects in severe cold regions

[0271] Severely cold areas Fee base Fee Rate Construction Engineering Labor cost 7.04％ Installation Engineering Labor cost 9.65％ Transmission line engineering Labor cost 10.27％

[0272] 5.3 Analysis of the rate of additional fees for maintenance projects in severe cold regions

[0273] This chapter sorts out and analyzes the original data of power grid maintenance projects in severe cold regions. It is found that labor efficiency reduction, machinery efficiency reduction, material increase and measures fees are still the main influencing factors of engineering construction additional costs. At the same time, the price level of the 2015 maintenance quota and the technical transformation quota is the same. Therefore, this article no longer separately calculates the additional cost rate of construction in severe cold regions for power grid maintenance projects. The growth rate of the additional cost rate of construction in severe cold regions measured by the technical transformation project compared with the additional cost rate of construction in severe cold regions in the 2015 technical transformation pre-regulation is used as the basis for calculating the additional cost rate of construction in severe cold regions for maintenance projects. The power grid maintenance project continues to use the 2015 calculation rules, with labor costs as the charging base, and the rate = ((9.65-6.21) / 6.21+1)*11.94% = 18.55%.

[0274] Part VI: Example Verification and Conclusion

[0275] According to the construction surcharge rate in severe cold areas under theoretical research, a 110kV substation technical transformation project and a line technical transformation project in severe cold areas were selected, and the data results of the two projects were calculated and compared with the actual values.

[0276] The verification results of the construction surcharge rate in severe cold regions are shown in Table 6-1-1:

[0277] Table 6-1-1 Verification results of construction surcharge rates in severe cold regions Unit: Yuan

[0278]

[0279] A 110kV substation project in a severely cold region was selected. The actual construction cost of the construction fee in the severely cold region was about 63,983 yuan, and the installation cost was about 16,451 yuan. After adjusting the rate, the construction cost of the construction fee in the severely cold region was about 62,735 yuan, and the installation cost was about 18,763 yuan. From the verification results, the actual construction fee in the severely cold region increased by about 16,047 yuan compared with the budget data of the 2015 version of the budget. After adjusting the rate of the construction fee in the severely cold region, the actual construction fee in the severely cold region in this area was only about 1,064 yuan less than the adjusted total. It can be seen that after adjusting the rate, the construction fee in the severely cold region is more consistent with the actual cost.

[0280] For a 110KV line project in a severely cold region, the actual additional cost of construction in a severely cold region is about 238,730 yuan, and the additional cost of construction in a severely cold region after adjusting the rate is about 238,178 yuan. Therefore, during the actual construction, the additional cost of construction in a severely cold region is about 238,730 yuan more than the budget; after adjusting the rate of additional cost of construction in a severely cold region, the actual additional cost of construction in a severely cold region is only about 553 yuan more than the total after adjustment. It can be seen that after adjusting the rate, the additional cost of construction in a severely cold region is more consistent with the actual cost.

[0281] 6.2 Conclusion

[0282] 6.2.1 Research Conclusion

[0283] This report studies the severely cold regions from the aspects of boundary scope, construction impact, and increased costs. Based on extensive research and consultation with multiple parties, it deeply studies the impact of different factors in various regions, combines the construction of power grid technical transformation and maintenance projects, uses scientific methods as a means, objectively and reasonably reflects the characteristics of engineering construction in severely cold regions and the social average cost as a code of conduct. Through research, measurement, comparison, and verification of the rationality and accuracy of the increased costs of construction in severely cold regions, the following conclusions are drawn:

[0284] 1. The area north of 45° north latitude is defined as a severely cold area for power grid technical transformation and maintenance projects.

[0285] 2. The calculation of construction surcharges in extremely cold areas is not based on voltage levels.

[0286] 3. The rates of additional construction fees in severe cold regions are as follows: Table 6-1 and Table 6-2:

[0287] Table 6-1 Rates of additional construction fees for technical transformation projects in severe cold regions

[0288]

[0289] Table 6-2 Rates of additional fees for maintenance projects in severe cold regions

[0290]

[0291] The modification description is that the power grid technical renovation and maintenance project of the present invention is constructed under severe cold conditions, and the construction increase fee reflects the reduction in labor efficiency, mechanical efficiency, increase in consumable material costs and increase in wrong charges on the basis of unchanged construction technology. However, in the actual construction process, the concrete construction of the building project will be affected by the temperature and the process will change significantly. Concrete mixing and curing require the construction of insulation sheds, etc. The supplementary quota for winter construction of concrete for power grid projects has been compiled and implemented by the State Grid Heilongjiang Electric Power Construction Quota Station. Because the winter construction process is the same, it is recommended that the technical renovation and maintenance project involving concrete winter construction projects refer to the supplementary quota for winter construction of concrete for power grid projects.

[0292] Appendix 1 Statistical analysis of labor efficiency reduction data of technical transformation projects

[0293]

[0294] Appendix 2 Statistical analysis of efficiency reduction data of engineering machinery for technical transformation

[0295]

[0296] Appendix 3 Statistical analysis table of the increase rate of fixed consumable material costs

[0297]

[0298] Appendix 4 Statistical analysis table of the increase ratio of fixed-rate measures fees

[0299]

[0300] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

[0301] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for calculating the additional fee coefficient for construction of power grid projects in severe cold regions, characterized in that: The steps include: S1, determine the scope of the severely cold regions for the power grid technical renovation and maintenance project; analyze the factors affecting the construction under severe cold conditions in the severely cold regions for the power grid technical renovation and maintenance project; S2, collecting the existing construction data of the power grid technical renovation and maintenance project that has been implemented in the severe cold area of ​​the power grid technical renovation and maintenance project determined in step S1; the existing construction data is related to the severe cold conditions construction influencing factors in step S1; S3, analyzing the construction engineering data in step S2 to obtain processed average data, S4, comparing the average data obtained in step S3 with the current pricing standard to obtain the required additional fee coefficient for construction in severe cold regions.

2. The calculation method of the charging coefficient of the additional fee for construction of power grid projects in severe cold regions according to claim 1 is characterized in that: In step S1, according to the standards and technical measures of the state, industry and power grid companies for construction under severe cold conditions, the scope of the severe cold region for the power grid technical renovation and maintenance project is determined to be: the area north of 45° north latitude.

3. The calculation method of the charging coefficient of the additional fee for construction of power grid projects in severe cold regions according to claim 2 is characterized in that: In step S1, the factors affecting construction under severe cold conditions include: reduced efficiency of labor, reduced efficiency of machinery, increased material consumption and increased cost of measures.

4. The calculation method of the charging coefficient of the construction fee increase for power grid projects in severe cold regions according to claim 3 is characterized in that: The artificial efficiency reduction includes: the impact of severe cold conditions on human physiological functions and the impact of severe cold conditions on personnel work efficiency; the mechanical efficiency reduction includes: the impact of severe cold on the performance of construction machinery and equipment and the impact of severe cold on the work efficiency of construction machinery and equipment; the increase in material consumption includes: the impact of severe cold on material consumption and the impact of severe cold on the unit price of materials; the increase in measures costs includes the impact of increased labor protection supplies, thermal insulation measures and anti-slip measures.

5. The calculation method of the charging coefficient of the additional fee for construction of power grid projects in severe cold regions according to claim 4 is characterized in that: The number of the implemented power grid technical transformation and maintenance projects is at least 10, and the implementing entities of the implemented power grid technical transformation and maintenance projects are at least 2.

6. The calculation method of the charging coefficient of the additional fee for construction of power grid projects in severe cold regions according to claim 5 is characterized in that: In step S4, the severe cold region construction includes severe cold region technical transformation project construction, and the severe cold region technical transformation project construction includes: construction projects, installation projects and power transmission line projects.

7. The method for calculating the charging coefficient of the additional construction fee for power grid projects in severe cold regions according to claim 6 is characterized in that the existing construction data in step S2 includes the actual measured values ​​of the artificial reduction efficiency of typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects, and the internal average method and the arithmetic mean method are used to obtain: the artificial reduction efficiency of the construction project, the artificial reduction efficiency of the substation installation project, and the artificial reduction efficiency of the transmission line project.

8. The method for calculating the additional fee coefficient for construction of power grid projects in severe cold regions according to claim 7 is characterized in that: The existing construction data in step S2 also include the measured values ​​of mechanical efficiency reduction of typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects, and the internal average method and the arithmetic mean method are used to obtain: the mechanical efficiency reduction of construction projects, the mechanical efficiency reduction of substation installation projects, and the mechanical efficiency reduction of transmission line projects, respectively.

9. The method for calculating the additional fee coefficient for construction of power grid projects in severe cold regions according to claim 8 is characterized in that: The existing construction data in step S2 also include the measured values ​​of the increase in material consumption of typical construction processes of construction projects, substation installation projects, and transmission line projects in the technical transformation and maintenance projects. A comparative analysis method is adopted, and the measured values ​​of the increase in material consumption of typical construction processes of construction projects, substation installation projects, and transmission line projects in the technical transformation and maintenance projects are used as comparative data. The quota consumable material cost is used as the benchmark data, and the same unit project is used as the analysis object. It is consistent and comparable in meeting the same functional requirements, so as to analyze the increase ratio of the quota consumable material cost in the severe cold environment, and use the internal average method of returning the data set for data processing to obtain the increase rate of material cost of each professional unit project in the severe cold area; then the arithmetic mean method is used to calculate and obtain the increase rate of material cost of construction projects, the increase rate of material cost of substation installation projects, and the increase rate of material cost of transmission line projects.

10. The method for calculating the additional fee coefficient for construction of power grid projects in severe cold regions according to claim 9 is characterized in that: The existing construction data in step S2 also include the measured values ​​of the increase in measures fees for typical construction processes of construction projects, substation installation projects, and transmission line projects in technical transformation and maintenance projects. The same project is taken as the analysis target, and it is consistent and comparable in meeting the same functional requirements, so as to analyze the increase ratio of measures fees in severe cold environments, and use the internal average method of returning the data set for data sorting, and calculate the increase rate of measures fees for each professional unit project in severe cold areas; then use the arithmetic mean method to calculate and obtain the increase rate of measures fees for construction projects, installation projects, and transmission line projects.

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