Quality evaluation method for cement product

Abstract

The invention discloses a quality evaluation method for a cement product, which comprises the following steps: defining indexes and contents of quality scoring factors, the quality scoring factors comprising a sampling process, working performance, mechanical performance and durability; constructing a judgment matrix according to the indexes and contents of the quality scoring factors, and reflecting the weights of the indexes in the judgment matrix; determining and calculating a single evaluation factor Ki in combination with the weight of the index of the quality scoring factor; defining a total evaluation factor K0, and calculating the total evaluation factor K0 according to the numerical value and the judgment condition of the single evaluation factor Ki; and determining a quality evaluation result of the cement product according to the total evaluation factor K0, wherein the quality evaluation result is the quality grade of the cement product. According to the technical scheme, detection personnel can be guided to judge the quality and the stability of the cement products such as cement concrete and mortar, so that the detection personnel are guided to optimize the mix proportion, the detection method and the like of the cement products, and the efficiency and the utilization rate of data analysis are further improved.

Description

Technical Field

[0001] The invention relates to the technical field of cement product quality assessment and treatment, and in particular to a quality assessment method for cement products. Background Art

[0002] As for cement products such as cement concrete and mortar quality, the current evaluation focuses mainly on the performance of cement products after hardening, such as whether the compressive strength and impermeability meet the specifications or design requirements, etc., but does not systematically evaluate the quality of cement products from the aspects of sampling process and working performance, such as concrete slump, air content, mortar consistency, etc.

[0003] In view of the problems existing in the above technologies, the present invention systematically analyzes the factors affecting the quality of concrete and mortar from four aspects: sampling process, working performance, mechanical properties, and durability, and establishes a set of systematic evaluation and treatment methods for evaluating the quality of concrete and mortar. Summary of the invention

[0004] To achieve the above object, the present invention provides a method for evaluating the quality of cement products, comprising the following steps:

[0005] Define the indicators and contents of quality scoring factors, including sampling process, working performance, mechanical properties and durability;

[0006] A hierarchical structure model is established according to the indicators and contents of the quality scoring factors, and a judgment matrix is ​​constructed, in which the weights of the indicators are reflected; the judgment matrix is ​​constructed by calculating the weights of the indicators included in each quality scoring factor using the AHP hierarchical analysis method;

[0007] Combined with the weights of the indicators of the quality scoring factors, determine and calculate the single assessment factor K i , where i = 1, 2, 3, 4, and the single item evaluation factor K i They are sampling process factor, working performance factor, mechanical property factor and durability performance factor;

[0008] Define the overall assessment factor K0, based on the individual assessment factors K i The total evaluation factor K0 is calculated based on the numerical value and judgment conditions;

[0009] The quality assessment result of the cement product is determined according to the total assessment factor K0, and the quality assessment result is the quality grade of the cement product. Wherein, cement products include: cement concrete and mortar.

[0010] Among them, the indicators of the sampling process include: sampling method, sampling means and sampling quantity;

[0011] The evaluation contents of each index during the sampling process include: whether the index value meets the specification requirements;

[0012] When the indicator is the sampling quantity, the evaluation content also includes: whether the sampling quantity can represent the pouring volume.

[0013] The indicators of working performance include: slump / spread, consistency, air content, water bleeding rate, setting time and bulk density;

[0014] When the indicators are slump / spread and consistency, the evaluation contents include: whether the indicator value meets the design requirements, the relationship between the measured value of the indicator and the design value;

[0015] When the index is gas content, the evaluation contents include: whether the index value meets the design requirements, the ratio of the calculated value of the index to the design value;

[0016] When the indicator is water seepage rate, the assessment content is the actual water seepage rate;

[0017] When the indicator is setting time, the evaluation content is: whether the setting time is appropriate and meets the requirements of on-site construction;

[0018] When the indicator is bulk density, the evaluation content is: whether the bulk density meets the requirements of the specification, and the difference between the calculated bulk density and the designed mix ratio.

[0019] The indicators of mechanical properties include: compressive strength; the evaluation content of the indicators refers to: whether the design and specification requirements are met.

[0020] The indicators of durability include: anti-seepage performance, anti-freezing performance and anti-abrasion performance;

[0021] When the indicator is durability performance, the evaluation content is: whether it meets the design requirements.

[0022] Among them, according to the durability, the cement products are classified into: those without durable materials and those with durable materials.

[0023] Furthermore, the single evaluation factor K i The calculation method is:

[0024] Where: i = 1, 2, 3, 4, j is the index number of each quality scoring factor, and index is m j is the corresponding weight of each indicator in the judgment matrix, x j is the score of each indicator, and n is the number of unit indicators of each factor.

[0025] The calculation method for the total assessment factor K0 is:

[0026] Where: m qis the weight of each factor unit; K i is the unit factor value of each factor.

[0027] Furthermore, the quality assessment result of cement products is determined according to the total assessment factor K0 by drawing a grade classification diagram;

[0028] Among them, the horizontal axis of the grade classification diagram is the interval state value of the K0 value, the vertical axis is the type of the test piece to be evaluated, and the content is the quality grade corresponding to the K0 value of the type of the test piece to be evaluated.

[0029] The quality assessment method for cement products provided by the present invention can systematically evaluate the quality and stability of cement products from the aspects of sampling process, working performance, mechanical properties and durability, define and calculate evaluation factors, establish grading principles, and draw grading charts, so as to intuitively determine the grades, treatment methods and suggestions of cement products such as cement concrete and mortar; through evaluation and analysis, it can guide test personnel to determine the quality and stability of cement products, guide test personnel to optimize the mix ratio and testing methods of cement products, and further improve the efficiency and utilization of data analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a step diagram of a method for evaluating the quality of cement products provided in an embodiment of the present invention;

[0031] Figure 2 is a logic flow chart of a quality assessment method for cement products provided in accordance with an embodiment of the present invention;

[0032] Figure 3 It is a level division diagram provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The present invention extracts relevant test and detection indicators from the test specifications of cement products (cement concrete and mortar), such as "Test Specifications for Hydraulic Concrete" and "Test Specifications for Cement and Cement Concrete for Highway Engineering", and extracts relevant sampling indicators from "Hydraulic Concrete Construction Specifications" and "Highway Engineering Quality Inspection and Evaluation Standards Volume 1 Civil Engineering". Combined with specific requirements in the detection work, the influence of various factors on the quality of cement products is analyzed, and an evaluation and processing method for systematically evaluating the quality of concrete and mortar is established to improve the efficiency and utilization rate of data analysis. The evaluation results can be used as a basis for detection personnel to judge the quality and stability of concrete and mortar, thereby guiding detection personnel to optimize and adjust the mix ratio, detection method, etc. of cement concrete and mortar.

[0034] The specific implementation of the present invention is described in detail below with reference to the accompanying drawings.

[0035] Figure 1The specific steps of the quality assessment method are provided, which specifically include the following steps:

[0036] Step S100: defining the indicators and contents of quality scoring factors;

[0037] In this step, determine the quality scoring factors and the indicators of the scoring factors, analyze the impact of various indicators on quality and related requirements, and further determine the evaluation content;

[0038] The quality scoring factors determined include: sampling process, working performance, mechanical properties and durability;

[0039] 1) Indicators of the sampling process include: sampling method, sampling means and sampling quantity;

[0040] The evaluation contents of each index in the sampling process mainly include: whether the index value meets the specification requirements;

[0041] When the indicator is the sampling quantity, the assessment also includes: whether the sampling quantity can represent the pouring volume.

[0042] 2) Performance indicators include: slump / spread, consistency, air content, water seepage rate, setting time and bulk density;

[0043] When the indicator is slump / spread, the evaluation contents include: whether the indicator value meets the design requirements, the relationship between the measured value of the indicator and the design value (whether it is close to the upper limit, close to the lower limit, or in the middle, etc.);

[0044] When the indicator is consistency, the evaluation content includes: whether the indicator value meets the design requirements, the relationship between the measured value of the indicator and the design value (close to the upper limit, close to the lower limit, or in the middle, etc.);

[0045] When the indicator is gas content, the evaluation contents include: whether the indicator value meets the design requirements, the ratio of the calculated value of the indicator to the design value;

[0046] When the indicator is water seepage rate, the assessment content is the actual water seepage rate;

[0047] When the indicator is setting time, the evaluation content is: whether the setting time is appropriate and meets the requirements of on-site construction;

[0048] When the indicator is bulk density, the evaluation content is: whether the bulk density meets the requirements of the specification, and the difference between the calculated bulk density and the designed mix ratio.

[0049] 3) Mechanical performance indicators include: compressive strength; the evaluation content of this indicator refers to: whether the compressive strength meets the design and specification requirements.

[0050] Specifically, if the compressive strength meets the design and specification requirements, it is further subdivided according to the ratio of the measured value to the design value.

[0051] For example: the ratio of the measured value to the design value of cement concrete in cement products cu The specific breakdown is as follows: ①f cu <0.95;②f cu ∈[0.95,1.15);③f cu ∈[1.15,1.50);④f cu ≥1.50.

[0052] The ratio f of the measured value and the designed value of mortar is specifically divided into the following categories: ①f<0.85; ②f∈[0.85,1.10); ③f∈[1.10,1.50); ​​④f≥1.50.

[0053] 4) Durability indicators include: anti-seepage performance, anti-freezing performance and anti-abrasion performance;

[0054] Among them, when the indicator is durability performance, the assessment content refers to: whether the durability performance meets the design requirements.

[0055] The present invention provides specific examples of quality scoring factors, corresponding indicators, contents and scoring principles for cement concrete and mortar, as shown in the following table:

[0056]

[0057]

[0058] Step S110: establishing a hierarchical model based on the indicators and contents of the quality scoring factors, constructing a judgment matrix, and determining the weights of the quality scoring factors in the judgment matrix;

[0059] In this step, the AHP hierarchy analysis method is used to calculate the weights of the indicators included in each quality scoring factor; during the calculation process, a judgment matrix of the indicators of each quality scoring factor is constructed, and the weights of each indicator are reflected in the judgment matrix.

[0060] 1) Sampling process: Establish a hierarchical structure model according to the sampling method, sampling means and sampling quantity in the industry, adopt the "1-9" scaling method to construct the sampling process judgment matrix, and reflect the weight of each indicator in the judgment matrix:

[0061] For example, a sample can be calculated as follows: ω1 = (0.1603, 0.1488, 0.6908) T, λ=3.0055, CR=0.005779, where ω1 is the weight set of three indicators, namely: the weights of sampling method, sampling means and sampling quantity are 0.16, 0.15 and 0.69 respectively, λ is the maximum eigenvalue, which is used to calculate the CI value by the scaling method and further calculate the CR value, CR is the consistency ratio CR=0.005779<0.1, indicating satisfactory consistency;;

[0062] According to the AHP analytic hierarchy process, the sampling process judgment matrix is ​​determined

[0063] 2) Workability: A hierarchical model is established based on the slump / expansion, air content, water bleeding rate, setting time and bulk density of cement concrete, and a workability judgment matrix is ​​constructed using the "1-9" scale method:

[0064] For example, a cement concrete sample can be calculated as follows:

[0065] ω2=(0.2691, 0.2806, 0.1979, 0.1361, 0.1104) T , λ=5.3888, CR=0.08643, that is, the slump / expansion, air content, water bleeding rate, setting time and bulk density weights are 0.27, 0.28, 0.20, 0.14 and 0.11 respectively; the consistency ratio CR=0.08643<0.1, indicating satisfactory consistency.

[0066] According to the AHP hierarchical analysis method, the working performance judgment matrix of cement concrete is determined as follows:

[0067]

[0068] On the other hand, for cement mortar, a hierarchical model is established according to consistency, air content, water bleeding rate, setting time and bulk density, and a "1-9" scale method is adopted to construct a work performance judgment matrix:

[0069] For example, a cement mortar sample can be calculated as follows: ω3 = (0.3540, 0.3540, 0.1607, 0.1353) T , λ=4.0206, CR=0.007565, that is, the weights of slump / expansion, air content, water bleeding rate, setting time and bulk density are 0.35, 0.35, 0.16 and 0.14 respectively, and the consistency ratio CR=0.04322<0.1, indicating satisfactory consistency;

[0070] According to the AHP hierarchical analysis method, the judgment matrix of cement mortar working performance is determined as the judgment matrix

[0071] 3) Mechanical properties: Since there is only one indicator, the weight is 1.00;

[0072] 4) The indicators included in the durability performance unit have the same importance, so their weights are directly divided equally, that is, the weights of cement concrete's impermeability, frost resistance and abrasion resistance are 0.33, 0.33 and 0.34 respectively; the weights of cement mortar's impermeability and frost resistance are 0.50 and 0.50 respectively.

[0073] Taking cement concrete and mortar as an example, they are divided into two categories according to whether they have durability requirements: materials without durability (cement concrete and mortar) and materials with durability (cement concrete and mortar).

[0074] 5) For materials without durability performance (cement concrete and mortar), a hierarchical model is established according to the sampling process, working performance and mechanical properties, and a judgment matrix without durability performance is constructed using a scaling method:

[0075] For example, a sample can be calculated to know that: ω4 = (0.1088, 0.1626, 0.7286) T , λ=3.0858, CR=0.08950, that is, the weights of sampling method, sampling means and sampling quantity are 0.11, 0.16 and 0.73 respectively; the consistency ratio CR=0.08950<0.1, indicating satisfactory consistency;

[0076] Then construct a judgment matrix without durability performance materials

[0077] 6) For materials with durability performance (cement concrete and mortar), a hierarchical model is established according to the sampling process, working performance and mechanical properties, and a judgment matrix of materials with durability performance is constructed using a scaling method:

[0078] For example, a sample can be calculated as follows: ω5 = (0.0823, 0.1195, 0.5304, 0.2753) T , λ=4.0811, CR=0.02971, that is: the weights of sampling process, working performance, mechanical properties and durability performance are 0.08, 0.11, 0.53 and 0.27 respectively; the consistency ratio CR=0.02971<0.1, indicating satisfactory consistency.

[0079] Then construct the material judgment matrix containing durability performance

[0080] Step S120: Determine and calculate the single item evaluation factor K in combination with the weight of the indicators of the quality scoring factor i , where i = 1, 2, 3, 4, and the single item evaluation factor K iThey are sampling process factor, working performance factor, mechanical property factor and durability performance factor;

[0081] Single item evaluation factor K i The calculation method is:

[0082]

[0083] Where: i is the serial number of the evaluation factor and i = 1, 2, 3, 4, j is the serial number of each indicator in the quality scoring factor, and the indicator is m j is the corresponding weight of each indicator in the judgment matrix, x j is the score of each indicator, and n is the number of unit indicators of each factor.

[0084] Step S130: define the overall evaluation factor K0, and i The total evaluation factor K0 is calculated based on the numerical value and judgment conditions;

[0085] The calculation method for the total assessment factor K0 is:

[0086]

[0087] Where: m q is the weight of each factor unit; K i is the unit factor value of each factor.

[0088] Step S140: determining a quality assessment result of the cement product according to the total assessment factor K0, where the quality assessment result is the quality grade of the cement product.

[0089] According to the weights and scores determined in step S120 and step S130, K is calculated. i (i=1,2,3,4); Before evaluating the mechanical properties and durability of cement concrete and mortar, the sampling process and working performance should meet certain basic conditions; based on this, the standard thresholds corresponding to the basic conditions are defined for K i (i=1,2,3,4) Initial judgment on the quality assessment of cement concrete and mortar performance.

[0090] For example:

[0091] For cement concrete: specify the standard threshold SK1 of the sampling process unit factor K1, and limit the sampling process to a number greater than or equal to the sampling frequency required by the specification, and the deviation allowed by the sampling method or sampling means is within a controllable range;

[0092] The standard threshold SK2 of the working performance unit factor K2 is specified, and the slump / spread, air content and water bleeding rate must meet the requirements of the specification. Under the premise of being qualified, the difference between the measured value and the design value is allowed; the setting time and bulk density are allowed to have a small deviation. In practical applications, SK1 = 0.85 and SK2 = 0.84 are set for cement concrete.

[0093] Similarly, for cement mortar:

[0094] Specify the standard threshold SK1 of the sampling process unit factor K1, and limit the sampling process to a sampling quantity that is greater than or equal to the sampling frequency required by the specification, and allow deviations in the sampling method or sampling means within a controllable range;

[0095] The standard threshold SK2 of the working performance unit factor K2 is specified, and the consistency and water seepage rate must meet the specification requirements. Under the premise of being qualified, the difference between the measured value and the design value is allowed; the setting time and bulk density are allowed to have a small deviation. In practical applications, SK1 = 0.85 and SK2 = 0.70 are set for cement mortar.

[0096] If the requirements of SK1 and SK2 are not met, the judgment requirements are not met.

[0097] When the judgment requirements are met, the quality assessment result of the cement product is determined based on the total assessment factor K0.

[0098] The present invention provides a method for determining the quality evaluation result of cement products by drawing a grade classification diagram. Specifically, the structure of the grade classification diagram is as follows: Figure 3 As shown, the horizontal axis is the interval state value of the K0 value, the vertical axis is the type of the test piece to be evaluated, and the content is the quality grade corresponding to the K0 value of the type of the test piece to be evaluated.

[0099] In the present invention, the grading diagram is graded according to the numerical range of the total evaluation factor K0, and the grading principle is shown in the following table:

[0100]

[0101]

[0102] Assessment level I: It means that the quality of cement concrete or mortar meets the specifications and design requirements, and the quality is stable, and there is no need to optimize the mix ratio and adjust the working performance of the mixture;

[0103] Assessment level II: It means that the quality of cement concrete or mortar meets the specifications and design requirements, but the measured compressive strength of cement concrete or mortar is greater than 1.5 times the design value, which increases ineffective costs and requires optimization of the mix ratio;

[0104] Assessment level III: It means that the working performance of some cement concrete or mortar does not meet the specifications and design requirements, and the measured compressive strength of cement concrete or mortar is greater than 1.5 times the design value, which increases ineffective costs and requires optimization of mix ratio and adjustment of working performance of the mixture;

[0105] Assessment level IV: It means that the quality of cement concrete or mortar does not meet the specifications or design requirements, and re-sampling should be carried out for testing, and the working performance of the mixture needs to be optimized and adjusted.

[0106] The present invention provides specific embodiments:

[0107] Example 1: Quality assessment of C25 secondary concrete;

[0108] The assessment process is as follows Figure 2 As shown,

[0109] Step S200: for the sampling process, obtain the sampling process factor:

[0110] During the sampling process, after obtaining each indicator, the values ​​were assigned as follows: sampling method (0.50 points), sampling means (1.00 points), and sampling quantity (1.00 points);

[0111]

[0112] Since K1≥SK1, that is, K1=0.92≥0.85, we can proceed to the subsequent judgment process;

[0113] Step S210: Obtaining work performance factors for work performance:

[0114] These include various indicators and their values: slump (1.10 points), air content (1.00 points), water seepage rate (0.90 points), setting time (1.00 points), bulk density (1.00 points);

[0115] In this step, calculate each individual assessment factor:

[0116]

[0117] Since K2≥SK2, that is, K2=1.01≥0.84, the subsequent determination process can be entered;

[0118] Step S220: Determine whether the sample is a material containing durable performance or a material containing no durable performance; if it is a material containing durable performance, proceed to step S230:

[0119] Obtain the mechanical property factor, i.e., compressive strength (0.90 points), and calculate the single evaluation factor as follows:

[0120]

[0121] K3≥0, the judgment condition is met, and the next step is entered, step S240: calculate the total evaluation factor K0:

[0122]

[0123] According to the evaluation grade classification principle, the C25 secondary concrete is rated as "Grade III", which means that some of the working performance of the concrete does not meet the specifications and design requirements, and the actual measured value of the concrete compressive strength is greater than 1.5 times the design value, which increases invalid costs. It is necessary to optimize the mix ratio, reduce the cement dosage, and adjust the water seepage rate of the mixture.

[0124] Example 2: Quality assessment of C40W6F100 three-graded anti-abrasion concrete: According to the scoring principle, the values ​​of each indicator are as follows: sampling method (1.00 point), sampling means (1.00 point), sampling quantity (0.50 point), slump (0.85 point), air content (1.00 point), water bleeding rate (0.50 point), setting time (1.00 point), bulk density (1.00 point), compressive strength (0.90 point), impermeability (1.00 point), antifreeze performance (1.00 point), anti-abrasion performance (1.00 point); the calculation of each single evaluation factor is as follows:

[0125]

[0126] From the calculation results, we can know that: K1=0.66<0.85, which does not meet the judgment conditions. According to the evaluation grade classification principle, the C40W6F100 three-graded impact-resistant concrete is rated as "Grade IV", which means that the concrete quality does not meet the specifications or design requirements. Re-sampling should be carried out for testing, and the detection method needs to be optimized and adjusted.

[0127] Example 3: Quality assessment of C25W6F100 secondary concrete: According to the scoring principle, the values ​​of each index are as follows: sampling method (1.00 point), sampling means (1.00 point), sampling quantity (1.05 point), slump (1.00 point), air content (0.80 point), water bleeding rate (1.00 point), setting time (1.00 point), bulk density (0.60 point), compressive strength (1.05 point), impermeability (1.00 point), frost resistance (1.00 point), and the calculation of each single evaluation factor is as follows:

[0128]

[0129] From the calculation results, we can know that: K1=1.03≥0.85 and K2=0.90≥0.84, which meets the judgment conditions. The total evaluation factor K0 is calculated as follows:

[0130]

[0131] According to the evaluation grade classification principle, the C25W6F100 secondary concrete is rated as "Grade I", which means that the quality of the concrete meets the specifications and design requirements, and the quality is stable, without the need to optimize the mix ratio and adjust the working performance of the mixture.

[0132] Example 4: Quality assessment of M25 antifreeze mortar: According to the scoring principle, the values ​​of each indicator are as follows: sampling method (0.50 points), sampling means (1.00 points), sampling quantity (1.00 points), consistency (1.10 points), water seepage rate (0.00 points), setting time (1.00 points), bulk density (0.60 points), compressive strength (1.00 points), antifreeze performance (1.00 points), and the calculation of each single evaluation factor is as follows:

[0133]

[0134]

[0135] From the calculation results, we can see that: K1=0.92≥0.85 but K2=0.63<0.70, which does not meet the judgment conditions. According to the evaluation grade classification principle, the M25 frost-resistant mortar is rated as "Grade IV", which means that the mortar quality does not meet the specifications or design requirements, and re-sampling should be carried out for testing. The working performance of the mixture, such as water seepage rate and bulk density, needs to be optimized and adjusted.

[0136] Example 5: Quality assessment of M30 anti-seepage mortar: According to the scoring principle, the values ​​of each indicator are as follows: sampling method (1.00 point), sampling means (1.00 point), sampling quantity (1.05 point), consistency (1.10 point), water seepage rate (1.00 point), setting time (1.00 point), bulk density (0.60 point), compressive strength (0.90 point), anti-seepage performance (1.00 point); the calculation of each single evaluation factor is as follows:

[0137]

[0138] From the calculation results, we know that: K1=1.03≥0.85 and K2=0.98≥0.70, which meets the judgment conditions. Calculate the total evaluation factor K0.

[0139]

[0140] According to the evaluation grade classification principle, the M30 anti-seepage mortar is rated as "Grade II", which means that the mortar quality meets the specifications and design requirements, but the actual measured compressive strength of the mortar is 1.5 times greater than the design value, which increases invalid costs and requires optimizing the mix ratio and reducing the cement consumption.

[0141] Through the quality assessment method of cement products provided by the present invention, the quality and stability of cement products such as cement concrete and mortar are systematically evaluated from the aspects of sampling process, working performance, mechanical properties and durability, evaluation factors are defined and calculated, grading principles are established, and grading diagrams are drawn to intuitively determine the grade, treatment methods and suggestions of cement products; through evaluation and analysis, the test personnel are guided in the judgment of the quality and stability of cement products, thereby guiding the test personnel to optimize the mix ratio, testing methods and the like of cement products, and further improve the efficiency and utilization of data analysis.

[0142] The above disclosures are only several specific embodiments of the present invention; however, the present invention is not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A method for evaluating the quality of cement products, characterized in that: The following steps are involved: Define the indicators and contents of quality scoring factors, which include: sampling process, working performance, mechanical properties and durability; A hierarchical model is established according to the indicators and contents of the quality scoring factors, and a judgment matrix is ​​constructed, in which the weights of the indicators are reflected; the judgment matrix is ​​constructed by calculating the weights of the indicators included in each quality scoring factor using the AHP hierarchical analysis method; Combined with the weights of the indicators of the quality scoring factors, determine and calculate the single assessment factor K i , where i = 1, 2, 3, 4, and the single item evaluation factor K i They are sampling process factor, working performance factor, mechanical property factor and durability performance factor; Define the overall assessment factor K0, based on the individual assessment factors K i The total evaluation factor K0 is calculated based on the numerical value and judgment conditions; The quality assessment result of the cement product is determined according to the total assessment factor K0, and the quality assessment result is the quality grade of the cement product.

2. The quality assessment method according to claim 1, characterized in that: The indicators of the sampling process include: sampling method, sampling means and sampling quantity; The evaluation contents of each index in the sampling process include: whether the index value meets the specification requirements; When the indicator is the sampling quantity, the evaluation content also includes: whether the sampling quantity can represent the pouring volume.

3. The quality assessment method according to claim 1, characterized in that: The indicators of the working performance include: slump / spread, consistency, air content, water bleeding rate, setting time and bulk density; When the indicators are slump / spread and consistency, the evaluation contents include: whether the indicator value meets the design requirements, the relationship between the measured value of the indicator and the design value; When the index is gas content, the evaluation contents include: whether the index value meets the design requirements, the ratio of the calculated value of the index to the design value; When the indicator is water seepage rate, the assessment content is the actual measured water seepage rate; When the indicator is setting time, the evaluation content is: whether the setting time is appropriate and meets the requirements of on-site construction; When the indicator is bulk density, the evaluation content is: whether the bulk density meets the requirements of the specification, and the difference between the calculated bulk density and the designed mix ratio.

4. The quality assessment method according to claim 1, characterized in that: The indicators of the mechanical properties include: compressive strength; the evaluation content of the indicators refers to: whether the design and specification requirements are met.

5. The quality assessment method according to claim 1, characterized in that: The indicators of durability include: anti-seepage performance, anti-freezing performance and anti-abrasion performance; When the indicator is durability performance, the evaluation content is: whether it meets the design requirements.

6. The quality assessment method according to claim 1, characterized in that: According to the durability, the cement products are classified into: those without durable materials and those with durable materials.

7. The quality assessment method according to claim 1, characterized in that: The single evaluation factor K i The calculation method is: Where: i = 1, 2, 3, 4, j is the index number of each quality scoring factor, and index is m j is the corresponding weight of each indicator in the judgment matrix, x j is the score of each indicator, and n is the number of unit indicators of each factor.

8. The quality assessment method according to claim 1, characterized in that: The calculation method of the total evaluation factor K0 is: Where: m q is the weight of each factor unit; K i is the unit factor value of each factor.

9. The quality assessment method according to claim 1, characterized in that: Determining the quality assessment result of the cement product according to the total assessment factor K0 is achieved by drawing a grade classification diagram; The horizontal axis of the grade classification diagram is the interval state value of the K0 value, the vertical axis is the type of the test piece to be evaluated, and the content is the quality grade corresponding to the K0 value of the type of the test piece to be evaluated.

10. The quality assessment method according to claim 1, characterized in that: The cement products include: cement concrete and mortar.

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