Comprehensive evaluation method for concrete performance

Abstract

The invention discloses a comprehensive evaluation method for concrete performance, and relates to the technical field of concrete.The method comprises the following steps that life cycle evaluation is conducted on concrete, and the environmental influence of the whole life cycle of the concrete is obtained; testing the porosity, apparent density and mechanical properties of the concrete, wherein the mechanical properties comprise compressive strength; recording the ratio of the environmental influence to the compressive strength as ecological strength efficiency; the environmental influence, the porosity, the apparent density, the compressive strength and the ecological strength efficiency are used as evaluation indexes, normalization processing is carried out, and the performance of different kinds of concrete is comprehensively evaluated. The method provided by the invention can evaluate the potential of different concretes in the aspect of reducing the environmental footprint, and can realize multi-scale evaluation of the comprehensive performance of different concretes, thereby providing a means for research and performance improvement of the concretes; and technical support is provided for better application of the concrete, how to reduce the influence of the concrete on the environment and development of green and environment-friendly concrete.

Description

Technical Field

[0001] The invention relates to the technical field of concrete, and in particular to a comprehensive evaluation method for concrete performance. Background Art

[0002] Concrete is one of the most widely used materials in construction projects. With its advantages of high strength, easy molding and economy, it plays a core role in a variety of structures. However, the performance evaluation of concrete (such as bottom ash concrete) is relatively simple, and it is impossible to fully understand the performance of concrete. In addition, in concrete construction, due to the large demand for concrete and the complicated construction process, it is inevitable that it will cause inestimable energy and material consumption. How to objectively and comprehensively evaluate the performance of different concretes has become an urgent problem to be solved.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] Based on the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a comprehensive evaluation method for concrete performance.

[0005] The technical solution of the present invention is as follows:

[0006] A first aspect of the present invention provides a method for comprehensive evaluation of concrete performance, comprising the following steps:

[0007] Conduct a life cycle assessment of concrete to obtain the environmental impact of concrete throughout its life cycle;

[0008] Testing the porosity, apparent density and mechanical properties of the concrete, wherein the mechanical properties include compressive strength; recording the ratio of environmental impact to compressive strength as ecological strength efficiency;

[0009] Environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency were used as evaluation indicators and normalized to comprehensively evaluate the performance of different concretes.

[0010] Optionally, the whole life cycle of concrete includes a raw material acquisition stage, a raw material transportation stage and a concrete production stage, wherein the raw material acquisition stage includes acquiring various raw materials required for concrete production, the raw material transportation stage includes transporting various raw materials required for concrete production to a concrete production site, and the concrete production stage includes producing concrete using the various raw materials;

[0011] The steps of conducting a life cycle assessment on concrete to obtain the environmental impact of the entire life cycle of concrete specifically include:

[0012] Obtain the environmental impact of the raw material acquisition stage, the environmental impact of the raw material transportation stage and the environmental impact of the concrete production stage;

[0013] The environmental impact of the raw material acquisition stage, the environmental impact of the raw material transportation stage and the environmental impact of the concrete production stage are added together to obtain the environmental impact of the entire life cycle of concrete.

[0014] Optionally, the steps of obtaining the environmental impact of the raw material acquisition stage specifically include:

[0015] Ecoinvent 3 and ELCD databases were used to conduct life cycle assessments on each raw material, and the environmental impact of each raw material over its entire life cycle was obtained, and then the environmental impact of the raw material acquisition stage was obtained.

[0016] Optionally, the step of obtaining the environmental impact of the raw material transportation stage specifically includes:

[0017] Determine the location of each raw material supplier and measure the distance between each raw material supplier and the concrete production site;

[0018] Get the environmental impact of transporting 1kg of raw materials for 1km;

[0019] The environmental impact of the raw material transportation stage is obtained based on the quality of each raw material required for concrete, the distance between each raw material supplier and the concrete production site, and the environmental impact of transporting 1kg of raw material for 1km.

[0020] Optionally, the environmental impact includes six indicators, namely, abiotic depletion potential, global warming potential, photochemical ozone production potential, acidification potential, eutrophication potential, and primary energy and non-renewable energy;

[0021] The abiotic depletion potential of the whole life cycle of concrete is the sum of the abiotic depletion potential of the raw material acquisition stage, the abiotic depletion potential of the raw material transportation stage and the abiotic depletion potential of the concrete production stage;

[0022] The global warming potential of the whole life cycle of concrete is the sum of the global warming potential of the raw material acquisition stage, the global warming potential of the raw material transportation stage and the global warming potential of the concrete production stage;

[0023] The photochemical ozone generation potential of the concrete in its entire life cycle is the sum of the photochemical ozone generation potential in the raw material acquisition stage, the photochemical ozone generation potential in the raw material transportation stage, and the photochemical ozone generation potential in the concrete production stage;

[0024] The acidification potential of the concrete in its entire life cycle is the sum of the acidification potential in the raw material acquisition stage, the acidification potential in the raw material transportation stage, and the acidification potential in the concrete production stage;

[0025] The eutrophication potential of the concrete in its entire life cycle is the sum of the eutrophication potential in the raw material acquisition stage, the eutrophication potential in the raw material transportation stage, and the eutrophication potential in the concrete production stage;

[0026] The primary energy and non-renewable energy in the entire life cycle of concrete are the sum of the primary energy and non-renewable energy in the raw material acquisition stage, the primary energy and non-renewable energy in the raw material transportation stage, and the primary energy and non-renewable energy in the concrete production stage.

[0027] Optionally, the raw materials include cement, municipal solid waste incineration bottom ash, water, coarse aggregate and fine aggregate.

[0028] Alternatively, the environmental impact of the entire life cycle of municipal solid waste incineration bottom ash is calculated using the following formula:

[0029]

[0030] Among them, EI BA The environmental impact of the entire life cycle of municipal solid waste incineration bottom ash, EI FA is the environmental impact of fly ash throughout its life cycle, R FA is the mass ratio of fly ash in the incineration ash of municipal solid waste, R BA It is the mass proportion of bottom ash in the incineration ash of municipal solid waste.

[0031] Alternatively, the porosity and apparent density of concrete can be tested using mercury intrusion porosimetry.

[0032] Optionally, the step of taking environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators and performing normalization processing to comprehensively evaluate the performance of different concretes specifically includes:

[0033] The environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency of different concretes are taken as evaluation indicators. After normalization, a radar chart is drawn to construct a comprehensive evaluation model of concrete performance to comprehensively evaluate the performance of different concretes.

[0034] Optionally, the mechanical properties also include tensile strength;

[0035] The comprehensive evaluation method of concrete performance also includes the following steps:

[0036] Testing concrete for workability, shrinkage and durability;

[0037] Environmental impact, porosity, apparent density, compressive strength, ecological strength efficiency, tensile strength, workability, shrinkage and durability were used as evaluation indicators and normalized to comprehensively evaluate the performance of different concretes.

[0038] Beneficial effects: The comprehensive evaluation method of concrete performance provided by the present invention can evaluate the potential of different concretes in reducing environmental footprint, and uses environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators, and performs normalization processing to achieve multi-scale evaluation of the comprehensive performance of different concretes, providing means for the research and performance improvement of concrete, and also providing technical support for the better application of concrete, how to reduce the impact of concrete on the environment, and the development of green and environmentally friendly concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The normalized values ​​of ADP, GWP, POCP, AP, EP and PE-NRE of each concrete were obtained using the normalization factor in Example 1.

[0040] Figure 2 is the compressive strength of different concretes in Example 1.

[0041] Figure 3 This is a radar chart of various properties of different concretes in Example 1. DETAILED DESCRIPTION

[0042] The present invention provides a comprehensive evaluation method for concrete performance. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0044] The embodiment of the present invention provides a comprehensive evaluation method for concrete performance, which includes the following steps:

[0045] S1. Conduct a life cycle assessment of concrete to obtain the environmental impact of concrete throughout its entire life cycle (i.e., from cradle to grave);

[0046] S2. Testing the porosity, apparent density and mechanical properties of the concrete, wherein the mechanical properties include compressive strength; recording the ratio of environmental impact to compressive strength as ecological strength efficiency;

[0047] S3. Environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency are used as evaluation indicators, and normalized processing is performed to comprehensively evaluate the performance of different concretes.

[0048] The comprehensive evaluation method for concrete performance provided by the present invention can evaluate the potential of different concretes in reducing environmental footprint, and uses environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators, and performs normalization processing to achieve multi-scale evaluation of the comprehensive performance of different concretes, providing means for the research and performance improvement of concrete, and also providing technical support for the better application of concrete, how to reduce the impact of concrete on the environment, and the development of green and environmentally friendly concrete.

[0049] In step S1, in some embodiments, the whole life cycle of concrete includes a raw material acquisition stage, a raw material transportation stage and a concrete production stage, wherein the raw material acquisition stage includes acquiring various raw materials required for concrete production, the raw material transportation stage includes transporting various raw materials required for concrete production to a concrete production site, and the concrete production stage includes producing concrete using the various raw materials (in the present invention, the whole life cycle of concrete does not consider the use, maintenance and removal of concrete);

[0050] The step of conducting a life cycle assessment on concrete to obtain the environmental impact of the entire life cycle of concrete (i.e., from cradle to grave) specifically includes the following step S11 (including steps S111, S1121, S1122, and S1123) and step S12:

[0051] S11. Environmental impacts of the raw material acquisition stage (which can be understood as the production process from scratch), the raw material transportation stage, and the concrete production stage;

[0052] In some specific implementations, the step of obtaining the environmental impact of the raw material acquisition stage specifically includes:

[0053] S111. Use Ecoinvent 3 and ELCD databases to conduct life cycle assessments on each raw material, and obtain the environmental impact of each raw material throughout its life cycle from cradle to grave, and then obtain the environmental impact of the raw material acquisition stage.

[0054] Among them, the environmental impact includes six indicators, namely abiotic depletion potential (ADP), global warming potential (GWP), photochemical ozone production potential (POCP), acidification potential (AP), eutrophication potential (EP) and primary energy and non-renewable energy (PE-NRE).

[0055] Taking the raw materials including cement, municipal solid waste incineration bottom ash (MSWIBA), water, coarse aggregate and fine aggregate as an example, the steps of obtaining the environmental impact of the raw material acquisition stage specifically include: using Ecoinvent 3 and ELCD databases, and utilizing the LCA (life cycle assessment or life cycle analysis) method, respectively, to conduct life cycle assessments on cement, municipal solid waste incineration bottom ash, water, coarse aggregate and fine aggregate, and respectively obtain the environmental impact of cement over its entire life cycle (including the above 6 indicators), the environmental impact of MSWIBA over its entire life cycle (including the above 6 indicators), the environmental impact of water over its entire life cycle (including the above 6 indicators), the environmental impact of coarse aggregate over its entire life cycle (including the above 6 indicators) and the environmental impact of fine aggregate over its entire life cycle (including the above 6 indicators), and add up each indicator to obtain the environmental impact of the raw material acquisition stage (including the above 6 indicators).

[0056] Among them, since the environmental impact of the entire life cycle of MSWIBA cannot be directly obtained from the database, the environmental impact of the entire life cycle of MSWIBA (that is, from cradle to grave) is calculated using the following formula:

[0057]

[0058] Among them, EI BA The environmental impact of the entire life cycle of MSWIBA, EI FA is the environmental impact of the entire life cycle of fly ash (FA) (which can be directly obtained through the database), R FA is the mass ratio of fly ash in the incineration ash of municipal solid waste, R BA It is the mass proportion of bottom ash in the incineration ash of municipal solid waste.

[0059] MSWIBA and FA are both slags after waste incineration, in which larger solid particles are deposited at the bottom of the incinerator and on the grate, which is called bottom ash, while fine particles float in the flue gas and enter the flue gas purification system with the flue gas. These fine particles constitute part of the fly ash. Another part of the fly ash comes from the limestone or activated carbon added during the flue gas purification process. They are captured together in the dust collector (electrostatic precipitator, bag filter, etc.), and some fine particles also settle at the bottom of the flue and chimney. These captured and settled fine particles are called incineration fly ash.

[0060] In some specific embodiments, the step of obtaining the environmental impact of the raw material transportation stage specifically includes:

[0061] S1121. Determine the location of each raw material supplier, and measure the distance between each raw material supplier and the concrete production site (for example, a concrete mixing plant);

[0062] Specifically, taking the raw materials including cement, municipal solid waste incineration bottom ash, water, coarse aggregate and fine aggregate as an example, the steps of determining the location of each raw material supplier and measuring the distance between each raw material supplier and the concrete production site specifically include:

[0063] Determine the locations of cement suppliers, municipal solid waste incineration bottom ash suppliers, water suppliers, coarse aggregate suppliers and fine aggregate suppliers, and measure the distances between the locations of cement suppliers, municipal solid waste incineration bottom ash suppliers, water suppliers, coarse aggregate suppliers and fine aggregate suppliers and the concrete production site.

[0064] S1122. Obtain the environmental impact of transporting 1kg of raw materials for 1km (including the above 6 indicators);

[0065] Specifically, it can be obtained through Ecoinvent 3 and ELCD databases.

[0066] S1123. According to the quality of each raw material required for concrete, the distance between each raw material supplier and the concrete production site, and the environmental impact of transporting 1 kg of raw material for 1 km (including the above 6 indicators), the environmental impact of the raw material transportation stage (including the above 6 indicators) is obtained.

[0067] For example, the raw materials include cement, MSWIBA, water, coarse aggregate and fine aggregate, wherein water can be directly obtained at the concrete production site, so the transportation of water is not considered.

[0068] Specifically, according to the quality of cement required for concrete, the distance between the cement supplier and the concrete production site, and the environmental impact of transporting 1 kg of raw materials for 1 km (such as ADP), the ADP of transporting cement is obtained, and the other 5 indicators of transporting cement are obtained in the same way. Similarly, the environmental impacts of transporting MSWIBA, coarse aggregate and fine aggregate are obtained respectively (including 6 indicators). Then, the ADP of transporting cement, the ADP of transporting MSWIBA, the ADP of transporting water, the ADP of transporting coarse aggregate and the ADP of transporting fine aggregate are added to obtain the ADP of the raw material transportation stage. Similarly, the GWP, POCP, AP, EP and PE-NRE of the raw material transportation stage are obtained.

[0069] In some specific embodiments, the environmental impact of the concrete production stage can be obtained through Ecoinvent 3 and ELCD data.

[0070] S12. Add the environmental impact of the raw material acquisition stage (including the above 6 indicators), the environmental impact of the raw material transportation stage (including the above 6 indicators) and the environmental impact of the concrete production stage (including the above 6 indicators) to obtain the environmental impact of the entire life cycle of concrete.

[0071] Specifically, the ADP of the raw material acquisition stage, the ADP of the raw material transportation stage, and the ADP of the concrete production stage are added to obtain the total ADP of the concrete throughout its life cycle; the GWP of the raw material acquisition stage, the GWP of the raw material transportation stage, and the GWP of the concrete production stage are added to obtain the total GWP of the concrete throughout its life cycle; the POCP of the raw material acquisition stage, the POCP of the raw material transportation stage, and the POCP of the concrete production stage are added to obtain the total POCP of the concrete throughout its life cycle; the AP of the raw material acquisition stage, the AP of the raw material transportation stage, and the AP of the concrete production stage are added to obtain the total AP of the concrete throughout its life cycle; the EP of the raw material acquisition stage, the EP of the raw material transportation stage, and the EP of the concrete production stage are added to obtain the total EP of the concrete throughout its life cycle; the PE-NRE of the raw material acquisition stage, the PE-NRE of the raw material transportation stage, and the PE-NRE of the concrete production stage are added to obtain the total PE-NRE of the concrete throughout its life cycle.

[0072] In addition, in order to facilitate the analysis of environmental impact, the normalized values ​​of the six indicators of environmental impact can be calculated by the normalization factors of each of the six indicators, and the normalized values ​​of the six indicators can be added to obtain the total normalized value of environmental impact, so as to compare the environmental impact separately. Furthermore, the ratio of the total normalized value of environmental impact to the compressive strength is recorded as the ecological strength efficiency.

[0073] For example, the ADP value is divided by the normalization factor of ADP to obtain the normalized value of ADP. Specific examples can be found in Tables 9 to 10 in Example 1. The ratio of the total normalized value of environmental impact to the compressive strength is used as the ecological strength efficiency. Specific examples can be found in Table 18 in the embodiment.

[0074] In step S2, in some embodiments, the porosity and apparent density of the concrete are tested using a mercury intrusion method.

[0075] In step S3, in some embodiments, the step of taking environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators and performing normalization processing to comprehensively evaluate the performance of different concretes specifically includes:

[0076] The environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency of different concretes are taken as evaluation indicators. After normalization (i.e. normalization from 0 to 1), a radar chart is drawn, and a comprehensive evaluation model of concrete performance is constructed to comprehensively evaluate the performance of different concretes.

[0077] In this embodiment, the comprehensive performance of different concretes can be intuitively evaluated through the radar chart model.

[0078] In addition, in some specific embodiments, the mechanical properties also include tensile strength;

[0079] The comprehensive evaluation method of concrete performance also includes the following steps:

[0080] Testing concrete for workability, shrinkage and durability;

[0081] Environmental impact, porosity, apparent density, compressive strength, ecological strength efficiency, tensile strength, workability, shrinkage and durability were used as evaluation indicators, and normalized from 0 to 1 to comprehensively evaluate the performance of different concretes. Taking the porosity of different concretes as an example, the minimum value of the porosity of different concretes was normalized to 1, and the maximum value of the porosity of different concretes was normalized to 0, and then the porosity of different concretes was normalized.

[0082] For environmental impact, the six indicators of different concretes can be divided by their respective normalization factors, and then added together to obtain the total normalized value of environmental impact, and then the total normalized value of environmental impact can be normalized from 0 to 1.

[0083] Through the method of this embodiment, various properties of concrete can be analyzed and evaluated more comprehensively.

[0084] Among them, workability is to evaluate the fluidity of concrete through slump or flow test. Shrinkage is calculated by making specimens of specific size and measuring the change in length during curing. Durability is obtained by conducting anti-permeability tests (such as water penetration tests), freeze-thaw cycle tests, chloride ion penetration tests, etc.

[0085] The present invention will be further described below by means of specific examples.

[0086] Some of the data in the following examples are in scientific notation, for example, 3.29E-10 is 3.29×10 -10 , 4.054E+02 is 4.054×10 2 , which is 405.4. The rest of the values ​​are similar.

[0087] Example 1

[0088] At present, the concrete industry is facing the problem of high carbon emissions and urgently needs sustainable development strategies to reduce the environmental burden. In the prior art, there have been studies on the use of municipal solid waste incineration bottom ash (MSWIBA) as a concrete auxiliary material, but these studies often focus on a single performance indicator, lack a comprehensive performance evaluation system, and lack analysis of the nonlinear effect of MSWIBA dosage on concrete performance. Therefore, this embodiment provides a systematic method to comprehensively evaluate the environmental impact, mechanical properties, hydration process and microstructure of bottom ash concrete.

[0089] The amounts of various raw materials used in concrete are shown in Table 1.

[0090] Table 1, 1m 3 Raw materials needed for concrete

[0091]

[0092]

[0093] This embodiment provides a comprehensive evaluation method for the performance of different bottom ash concrete, comprising the following steps:

[0094] (1) Environmental impact (EI) of raw material acquisition

[0095] a. Obtain the EI of 1 kg of each raw material

[0096] Through Ecoinvent 3 and ELCD database, the ADP index, GWP index, POCP index, AP index, EP index and Pe-NRe index of 1kg cement were obtained; the ADP index, GWP index, POCP index, AP index, EP index and Pe-NRe index of 1kg water; the ADP index, GWP index, POCP index, AP index, EP index and Pe-NRe index of 1kg fine sand; the ADP index, GWP index, POCP index, AP index, EP index and Pe-NRe index of 1kg coarse sand were obtained.

[0097] pass (The meaning of each symbol is as described above), and the ADP index, GWP index, POCP index, AP index, EP index and Pe-NRe index of 1 kg of MSWIBA are obtained. The data results are shown in Figure 2. Among them, EI FA The data comes from the International EPD system. FA =65.8%, R BA =40.9%

[0098] Table 2. EI data of 1kg MSWIBA

[0099]

[0100]

[0101] The EI results of 1 kg of each raw material in the acquisition stage are shown in Table 3.

[0102] Table 3. EI of 1 kg of each raw material from cradle to grave

[0103]

[0104] b. Get (or calculate) 1m 3 EI of raw materials required for concrete at the raw materials acquisition stage

[0105] b1. Calculate 1m 3 ADP of raw materials required for concrete during the raw materials acquisition stage

[0106] 1m 3 The ADP of the raw materials required for concrete at the raw material acquisition stage is the ADP of cement (i.e. the ADP of 1 kg of cement is equal to the ADP of 1 m 3 The product of the mass of cement required for concrete), the ADP of MSWIBA (i.e. the ADP of 1 kg of MSWIBA and 1 m 3 The product of the mass of MSWIBA required for concrete), the ADP of water (i.e. the ADP of 1 kg of water and 1 m 3 The product of the mass of water required for concrete), the ADP of fine sand (i.e. the ADP of 1 kg of fine sand and 1 m 3 The product of the mass of fine sand required for concrete) and the ADP of coarse sand (i.e. the ADP of 1 kg of coarse sand and the ADP of 1 m 3 The sum of the mass of coarse sand required for concrete is calculated using Table 1 and Table 3, i.e. 1m 3 The ADP of concrete S is: 411.1×(1.00E-06)+0×(2.04E-10)+185×(1.57E-11)+648.865×0+1205.035×(6.24E-09)=4.186E-04; and so on, 1m 3 The ADP of concrete S1 is 3.774E-04; 1m 3 The ADP of concrete S2 is 3.363E-04; 1m 3 The ADP of concrete S3 is 2.952E-04; 1m 3 The ADP of concrete S4 is 2.542E-04; 1m 3 The ADP of concrete S5 is 2.131E-04; 1m 3 The ADP of concrete S6 is 1.720E-04;

[0107] b2. Calculate 1m 3 GWP of raw materials required for concrete during the raw material acquisition stage

[0108] 1m 3 The GWP of the raw materials required for concrete at the raw material acquisition stage is the sum of the GWP of cement, the GWP of MSWIBA, the GWP of water, the GWP of fine sand and the GWP of fine sand. It is calculated through Tables 1 and 3. Referring to the ADP algorithm, the GWP of 1m 3GWP of concrete S, S1, S2, S3, S4, S5 and S6.

[0109] b3. Calculate 1m 3 POCP of raw materials required for concrete at the raw materials acquisition stage

[0110] 1m 3 The POCP of the raw materials required for concrete at the raw material acquisition stage is the sum of the POCP of cement, the POCP of MSWIBA, the GWP of water, the POCP of fine sand and the POCP of fine sand. It is calculated according to Tables 1 and 3. Referring to the ADP algorithm, the POCP of 1m 3 POCP of concrete S, S1, S2, S3, S4, S5 and S6.

[0111] b4. Calculate 1m 3 AP of raw materials required for concrete in the raw materials acquisition stage

[0112] 1m 3 The AP of the raw materials required for concrete in the raw material acquisition stage is the sum of the AP of cement, the AP of MSWIBA, the AP of water, the AP of fine sand and the AP of fine sand. It is calculated by referring to the ADP algorithm and 1m 3 AP of concrete S, S1, S2, S3, S4, S5 and S6.

[0113] b5. Calculate 1m 3 Pe-NRe of raw materials required for concrete at the raw material acquisition stage

[0114] 1m 3 The Pe-NRe of the raw materials required for concrete in the raw material acquisition stage is the sum of the Pe-NRe of cement, the Pe-NRe of MSWIBA, the Pe-NRe of water, the Pe-NRe of fine sand and the Pe-NRe of fine sand. It is calculated by referring to the algorithm of ADP and 1m 3 Pe-NRe of concrete S, S1, S2, S3, S4, S5 and S6.

[0115] 1m 3 The EI of the raw materials required for concrete in the raw material acquisition stage is shown in Table 4.

[0116] Table 4, 1m 3 EI of concrete at the raw material acquisition stage

[0117]

[0118]

[0119] (2) Obtaining EI at the raw material transportation stage

[0120] a. Determine the location of the main raw material suppliers (such as Figure 1 As shown in the figure, the distance of each raw material transported to the concrete mixing station is measured. The location data is obtained in Shenzhen, China. The transportation distance from the fine sand and coarse sand supplier (the same supplier) to the concrete mixing station is 10km, the transportation distance from the MSWIBA supplier to the concrete mixing station is 10km, and the transportation distance from the cement supplier to the concrete mixing station is 9km (in this step, the transportation distance of water is not included, and it is assumed that the concrete mixing station provides water).

[0121] b. Obtain the EI per kilometer (km) of transporting 1 kg of raw materials, where the transport distance is increased by 70% taking into account the impact of air freight. See Table 5 for details.

[0122] Table 5. EI per km of transporting 1 kg of raw materials

[0123]

[0124] c. According to the distance of each raw material transported to the concrete mixing station, 1m 3 The mass of each raw material required for concrete and the EI of transporting 1kg of raw material per km are used to obtain the environmental impact of the logistics and transportation stage.

[0125] For concrete S, the ADP of its raw material transportation stage is the sum of the ADP of cement transportation, the ADP of MSWIBA transportation, the ADP of water transportation, and the ADP of fine sand and coarse sand transportation. 3 The mass of cement required for concrete S (411.1 kg) is multiplied by the transportation distance from the cement supplier to the concrete mixing plant (9 km) and the ADP per km for transporting 1 kg of raw material (2.62E-12). The same calculation is used for the ADP of other raw materials.

[0126] Then for concrete S, the ADP of its raw material transportation stage is specifically 411.1×9×(2.62E-12)+0×10×(2.62E-12)+(648.865+1205.035)×10×(2.62E-12)=5.827E-08. After calculation, its GWP of raw material transportation stage is 1.461, its POCP of raw material transportation stage is 4.982E-04, its AP of raw material transportation stage is 6.916E-03, its EP of raw material transportation stage is 1.601E-03, and its Pe-NRe is 20.615. Referring to the above method, the ADP, GWP, POCP, AP, EP, PE-NRE of concrete S, S1, S2, S3, S4, S5 and S6 are calculated respectively, and the results are shown in Table 6.

[0127] Table 6, 1m 3EI of concrete during raw material transportation

[0128]

[0129] (3) Prepare concrete and obtain EI during the concrete production stage

[0130] The preparation method of concrete is as follows:

[0131] Cement, MSWIBA, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S1 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S1.

[0132] Cement, MSWIBA, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S2 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S2.

[0133] Cement, MSWIBA, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S3 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S3.

[0134] Cement, MSWIBA, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S4 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S4.

[0135] Cement, MSWIBA, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S5 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S5.

[0136] Cement, bottom ash, water, fine natural aggregate and coarse natural aggregate were mixed according to the amounts of concrete S6 in Table 1, put into a mold, and cured for 28 days to obtain concrete, which was recorded as S6.

[0137] The amount of cement, bottom ash, water, fine natural aggregate and coarse natural aggregate in accordance with the concrete S in Table 1 and the specification GB JGJ 55-2011 were used to prepare concrete with C45 strength, denoted as S, which is the control group.

[0138] Obtain the EI of the concrete production stage, including energy consumption and water consumption. This data comes from the Ecoinvent3 and ELCD databases, as shown in Table 7.

[0139] Table 7, per m 3 EI of concrete during production

[0140]

[0141] (4) Calculate 1m 3 Cradle-to-grave EI of concrete (including 6 indicators, namely total ADP, total GWP, total POCP, total AP, total EP and total PE-NRE)

[0142] 1m 3 The EI of concrete from cradle to grave is the sum of the EI of the raw material acquisition stage, the EI of the raw material transportation stage and the EI of the concrete preparation process. For example, the total ADP of concrete is the sum of the ADP of the raw material acquisition stage (4.186E-04), the ADP of the raw material transportation stage (5.827E-08) and the ADP of the concrete preparation process (5.50E-07), that is, 4.192E-04. The calculation method of total GWP, total POCP, total AP, total EP and total PE-NRE refers to the calculation method of total ADP. See Table 8 for specific data.

[0143] Table 8, 1m 3 Total EI of concrete from cradle to grave

[0144]

[0145] The normalization factors of the six indicators of EI (obtained from Global environmental impacts: data sources and methodological choices for calculating normalization factors for LCA, Eleonora Crenna1, The International Journal of Life Cycle Assessment) are shown in Table 9.

[0146] Table 9. Normalization factors

[0147]

[0148] In order to facilitate analysis and comparison, the EI of each concrete is normalized using the normalization factor of EI. Specifically, the normalized total ADP value of each concrete is the total ADP value (see Table 8) divided by the normalization factor of ADP (see Table 9), and the normalized total ADP value is obtained. For example, the normalized total ADP value of concrete S is the total ADP value (4.192E-04, see Table 8) divided by the normalization factor of ADP (4.39E+8, see Table 9), and the normalized total ADP value is 9.544E-13. The normalized values ​​of the remaining indicators of concrete S and the normalized values ​​of the indicators of the remaining concretes are similar.

[0149] The total normalized EI value of each concrete is the sum of the values ​​of each index divided by the normalization factor of each index (i.e., the sum of the total ADP normalized value, the total GWP normalized value, the total POCP normalized value, the total AP normalized value, the total EP normalized value and the total PE-NRE normalized value). For example, the EI normalized value of concrete S is (4.192E-04) / (4.39E+8)+(4.115E+02) / (5.55E+13)+(7. 167E-02) / (2.80E+11)+(8.522E-01 / (3.83E+11)+(1.368E-01) / (1.11E+10)+(2.105E+03) / (4.48E+14)=2.789E-11. According to this method, the total normalized EI values ​​of concrete S1, S2, S3, S4, S5, and S6 are calculated respectively. The results are shown in Table 10. The normalized values ​​of each concrete are also shown in Table 10. Figure 1 shown.

[0150] Table 10. Normalized values ​​of different EI of different concretes

[0151]

[0152] 1m 3 The proportions of EI in each stage of concrete from cradle to grave, such as EI in raw material acquisition stage, EI in raw material transportation stage and EI in concrete production stage, are shown in Tables 11 to 16.

[0153] Table 11. ADP percentage results for each stage

[0154]

[0155]

[0156] Table 12. Results of the proportion of GWP in each stage

[0157]

[0158] Table 13. Proportion of POCP in each stage

[0159]

[0160]

[0161] Table 14. Results of AP ratio in each stage

[0162]

[0163] Table 15. Results of the proportion of EPs in each stage

[0164]

[0165]

[0166] Table 16. Proportion of PE-NRe in each stage

[0167]

[0168] (5) Compressive strength test

[0169] The compressive strength of the concrete was tested according to the Chinese national standard GB / T 50081. The results are shown in Table 17 and Table 18. Figure 2 shown.

[0170] Table 17. Compressive strength of various concretes

[0171]

[0172]

[0173] (6) Calculation of ecological intensity efficiency

[0174] Using the data in Tables 10 and 17, the ratio of the total normalized value of each EI to the compressive strength is calculated as the ecological strength efficiency. The results are shown in Tables 18 and Figure 3 shown.

[0175] Table 18. Ecological strength efficiency of various concretes

[0176]

[0177] (7) Porosity and surface density test

[0178] The porosity and surface density of the above concrete were tested by mercury intrusion porosimetry. The results are shown in Table 19.

[0179] Table 19. Porosity and apparent density of each concrete

[0180]

[0181] (8) The total normalized EI value (Table 10), compressive strength, porosity, apparent density and ecological strength efficiency of the above concretes were normalized from 0 to 1. The results are shown in Tables 20 and Figure 3 shown.

[0182] For example, the smaller the total normalized value of EI, the better. Therefore, the minimum total normalized value of EI in concrete (1.557E-11, see Table 10) is normalized to 1, and the maximum total normalized value of EI (2.789E-11) is normalized to 0. Then, the normalized value of the total normalized value of EI of concrete S2 is [(2.372E-11)-(2.789E-11)] / [(1.557E-11)-(2.789E-11)]=0.338, and the algorithms for other concretes are similar.

[0183] For another example, the larger the compressive strength, the better. Therefore, the maximum compressive strength (56.81 MPa, see Table 17) of each concrete is normalized to 1, and the minimum compressive strength (12.64 MPa, see Table 15) is normalized to 0. Then, the normalized compressive strength value of concrete S2 is (31.26-12.64) / (58.61-12.64)=0.421, and the algorithms for the remaining concretes are similar.

[0184] For another example, the smaller the porosity, the better. Therefore, the minimum porosity value (12.236%, see Table 19) in each concrete is normalized to 1, and the maximum porosity value (19.055%, see Table 19) is normalized to 0. Then, the normalized porosity value of concrete S2 is (15.361%-19.055%) / (12.236%-19.055%)=0.542, and the algorithms for other concretes are similar.

[0185] The larger the apparent density, the better. Therefore, the algorithm for normalizing the apparent density refers to the normalization of the compressive strength.

[0186] The smaller the value of ecological intensity efficiency, the better. Therefore, the algorithm for normalizing the ecological intensity efficiency refers to the normalization of porosity.

[0187] Use the normalized values ​​of the above indicators to draw a radar chart, such as Figure 3 shown.

[0188] Table 20. Data of various indicators of concrete after normalization from 0 to 1

[0189]

[0190]

[0191] analyze:

[0192] Abiotic depletion potential (ADP) is an EI index that can be used to evaluate the exploitation of limited resources (fossil fuels, minerals, etc.). Table 11 shows the proportion of ADP in the total ADP at different stages of the concrete life cycle. The proportion of the raw material acquisition stage in the total ADP is almost equivalent to 100% of the total. Therefore, the addition of MSWIBA is a good solution to reduce the ADP of concrete. At the same time, it can be seen from Table 11 that with the increase of the content of MSWIBA in concrete, the total ADP gradually decreases.

[0193] Global warming potential (GWP) is an indicator used to evaluate "greenhouse gas" emissions. Greenhouse gases cause temperatures to rise. Table 12 shows that when the MSWIBA replacement ratio for cement is in the range of 0% to 60%, the GWP is reduced by 54%. The same trend is also seen in ADP. In addition, a large amount of CO2 is produced due to the decomposition of calcium carbonate during cement production, and cement contributes about 87%-96% to the global warming potential. Therefore, MSWIBA replacing cement can reduce GWP. Further, Table 12 shows that the raw material transportation stage (transportation) accounts for approximately 0.36% to 0.77% of the total GWP.

[0194] Photochemical ozone generation potential (POCP) is highly toxic, affects human health and damages ecosystems. Table 13 shows that when the MSWIBA replacement ratio of cement increases from 0 to 60%, POCP decreases by 49%. In addition, it can be seen from Table 3 that in the raw material acquisition stage, the contribution of MSWIBA (POCP is 3.41E-07kg C2H4 eq, see Table 3) to the total POCP is much smaller than the contribution of cement (1.42E-04kgC2H4 eq, see Table 2) to the total POCP. Therefore, replacing cement with MSWIBA can significantly reduce the photochemical ozone generation potential of concrete.

[0195] Sulfur dioxide from fossil fuels is the main cause of acidification. Soil moisture affects the pH value of the environment and destroys the balance between ecosystems and buildings. Table 14 shows the AP of concrete over the entire life cycle under different MSWIBA replacement cement ratios. When the MSWIBA replacement cement ratio increases from 0 to 60%, the total AP decreases by 43%. The raw material acquisition stage is the main contributor to AP, among which the AP of cement is 0.00148kg SO2eq (see Table 3), which is much larger than the AP of MSWIBA (4.51E-06kg SO2eq, see Table 3).

[0196] Eutrophication potential (EP) refers to the enrichment of nutrients in a particular area due to pollution from wastewater and fertilizers. This can lead to low solar energy utilization and the death of plants and flowers due to excessive development of algae. Table 15 shows that when the MSWIBA replacement cement ratio increases from 0% to 60%, the EP decreases by 43%. The raw material acquisition stage is the main contributor to the total EP of concrete. Among them, the EP of cement is 2.11E-04kg PO4 3- eq, higher than 6.53E-07kg PO4 of MSWIBA 3- eq (see Table 3), so replacing cement with MSWIBA will significantly reduce the EP of concrete.

[0197] Primary energy and non-renewable energy (PE-NRe) is an important indicator of EI. As can be seen from Table 16, when the MSWIBA replacement ratio of cement increases from 0% to 60%, PE-NRe decreases by 43%. In addition, it can be seen from Table 16 that the proportion of concrete production stage and raw material transportation stage increases with the increase of MSWIBA replacement rate. In addition, the raw material acquisition stage is also the main contributor to the total PE-NRe. According to the raw material PE-NRE data, the PE-NRE of cement is 3.7MJ (see Table 3), and that of MSWIBA is 2.67E-02MJ (see Table 3). Therefore, the addition of MSWIBA will reduce the utilization rate of primary non-renewable energy in concrete.

[0198] In addition, it can be seen from Tables 8 and 10 that the six EI indicators of concrete show similar trends. The six EI indicators all show a downward trend with the increase of MSWIBA content in concrete (the proportion of MSWIBA replacing cement increases). This is because, compared with other raw materials, the production process of cement in concrete will produce many harmful gases, including greenhouse gases such as SO2 and CO2, and consume a lot of energy. However, using MSWIBA to partially replace cement can effectively reduce the generation of toxic and harmful gases and reduce energy consumption.

[0199] Figure 1 , Figure 2 The results in Table 10 show that although the addition of MSWIBA reduces the compressive strength of concrete, the total normalized value of EI decreases with the increase of the content of MSWIBA in concrete. Among them, EP and GWP are the main factors causing the difference in the total normalized value of EI. In addition, compared with the control group (concrete S), the total normalized values ​​of EI of S1, S2, S3, S4, S5 and S6 decreased by 7.5%, 15.1%, 22.2%, 29.7%, 36.9% and 44.1%, respectively.

[0200] After normalization from 0 to 1, the environmental impact, compressive strength, porosity, apparent density and ecological strength efficiency are listed in Table 20, and a radar chart is drawn as shown in Figure 3 As shown in the figure, the larger the closed area of ​​the curve, the better the comprehensive performance. The results show that the comprehensive properties of S3 are relatively balanced. When the MSWIBA content is 20% to 40%, the concrete can maintain good mechanical properties, which provides a theoretical basis for practical application.

[0201] In summary, the present invention provides a comprehensive evaluation method for concrete performance. The comprehensive evaluation method for concrete performance provided by the present invention can evaluate the potential of different concretes in reducing environmental footprint, and uses environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators, and performs normalization processing to achieve multi-scale evaluation of the comprehensive performance of different concretes, providing means for the research and performance improvement of concrete, and also providing technical support for better application of concrete, how to reduce the impact of concrete on the environment, and develop green and environmentally friendly concrete.

[0202] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A comprehensive evaluation method for concrete performance, It is characterized in that The steps include: Conduct a life cycle assessment of concrete to obtain the environmental impact of concrete throughout its life cycle; Testing the porosity, apparent density and mechanical properties of the concrete, wherein the mechanical properties include compressive strength; recording the ratio of environmental impact to compressive strength as ecological strength efficiency; Environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency were used as evaluation indicators and normalized to comprehensively evaluate the performance of different concretes.

2. The comprehensive evaluation method for concrete performance according to claim 1, It is characterized in that The whole life cycle of concrete includes a raw material acquisition stage, a raw material transportation stage and a concrete production stage, wherein the raw material acquisition stage includes acquiring various raw materials required for concrete production, the raw material transportation stage includes transporting various raw materials required for concrete production to a concrete production site, and the concrete production stage includes producing concrete using the various raw materials; The steps of conducting a life cycle assessment on concrete to obtain the environmental impact of the entire life cycle of concrete specifically include: Obtain the environmental impact of the raw material acquisition stage, the environmental impact of the raw material transportation stage and the environmental impact of the concrete production stage; The environmental impact of the raw material acquisition stage, the environmental impact of the raw material transportation stage and the environmental impact of the concrete production stage are added together to obtain the environmental impact of the entire life cycle of concrete.

3. The comprehensive evaluation method for concrete performance according to claim 2, It is characterized in that The steps to obtain the environmental impact of the raw material acquisition stage include: Ecoinvent 3 and ELCD databases were used to conduct life cycle assessments on each raw material, and the environmental impact of each raw material over its entire life cycle was obtained, and then the environmental impact of the raw material acquisition stage was obtained.

4. The comprehensive evaluation method for concrete performance according to claim 2, It is characterized in that The specific steps to obtain the environmental impact of the raw material transportation stage include: Determine the location of each raw material supplier and measure the distance between each raw material supplier and the concrete production site; Get the environmental impact of transporting 1kg of raw materials for 1km; The environmental impact of the raw material transportation stage is obtained based on the quality of each raw material required for concrete, the distance between each raw material supplier and the concrete production site, and the environmental impact of transporting 1kg of raw material for 1km.

5. The comprehensive evaluation method for concrete performance according to any one of claims 1 to 4, It is characterized in that The environmental impacts include six indicators, namely abiotic depletion potential, global warming potential, photochemical ozone production potential, acidification potential, eutrophication potential, and primary and non-renewable energy; The abiotic depletion potential of the whole life cycle of concrete is the sum of the abiotic depletion potential of the raw material acquisition stage, the abiotic depletion potential of the raw material transportation stage and the abiotic depletion potential of the concrete production stage; The global warming potential of the whole life cycle of concrete is the sum of the global warming potential of the raw material acquisition stage, the global warming potential of the raw material transportation stage and the global warming potential of the concrete production stage; The photochemical ozone generation potential of the concrete in its entire life cycle is the sum of the photochemical ozone generation potential in the raw material acquisition stage, the photochemical ozone generation potential in the raw material transportation stage, and the photochemical ozone generation potential in the concrete production stage; The acidification potential of the concrete in its entire life cycle is the sum of the acidification potential in the raw material acquisition stage, the acidification potential in the raw material transportation stage, and the acidification potential in the concrete production stage; The eutrophication potential of the concrete in its entire life cycle is the sum of the eutrophication potential in the raw material acquisition stage, the eutrophication potential in the raw material transportation stage, and the eutrophication potential in the concrete production stage; The primary energy and non-renewable energy in the entire life cycle of concrete are the sum of the primary energy and non-renewable energy in the raw material acquisition stage, the primary energy and non-renewable energy in the raw material transportation stage, and the primary energy and non-renewable energy in the concrete production stage.

6. The comprehensive evaluation method for concrete performance according to claim 3, It is characterized in that The raw materials include cement, bottom ash from the incineration of urban solid waste, water, coarse aggregate and fine aggregate.

7. The comprehensive evaluation method for concrete performance according to claim 6, It is characterized in that The environmental impact of the entire life cycle of municipal solid waste incineration bottom ash is calculated using the following formula: Among them, EI BA The environmental impact of the entire life cycle of municipal solid waste incineration bottom ash, EI FA is the environmental impact of fly ash throughout its life cycle, R FA is the mass ratio of fly ash in the incineration ash of municipal solid waste, R BA It is the mass proportion of bottom ash in the incineration ash of municipal solid waste.

8. The comprehensive evaluation method for concrete performance according to claim 1, It is characterized in that The porosity and apparent density of concrete were tested by mercury intrusion porosimetry.

9. The comprehensive evaluation method for concrete performance according to claim 1, It is characterized in that The steps of taking environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency as evaluation indicators and performing normalization processing to comprehensively evaluate the performance of different concretes specifically include: The environmental impact, porosity, apparent density, compressive strength and ecological strength efficiency of different concretes are taken as evaluation indicators. After normalization, a radar chart is drawn to construct a comprehensive evaluation model of concrete performance to comprehensively evaluate the performance of different concretes.

10. The comprehensive evaluation method for concrete performance according to claim 1, It is characterized in that The mechanical properties also include tensile strength; The comprehensive evaluation method of concrete performance also includes the following steps: Testing concrete for workability, shrinkage and durability; Environmental impact, porosity, apparent density, compressive strength, ecological strength efficiency, tensile strength, workability, shrinkage and durability were used as evaluation indicators and normalized to comprehensively evaluate the performance of different concretes.

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