CN-115775603-B - Design method of composite cementing material composition of rapid hardening early-strength concrete

Abstract

The application discloses a design method of composite cementing material composition of quick-hardening early-strength concrete, which comprises the steps of selecting each component of the composite cementing material according to the molar ratio of chemical components meeting specific conditions, taking the compressive strength of clean slurry as a response variable, carrying out polynomial fitting regression on test data to obtain a mathematical model related to the composite cementing material composition design, carrying out regression calculation on the mathematical model related to the composite cementing material composition design by setting the target content range of expected components and the expected target compressive strength, and obtaining the design proportion of the composite cementing material composition meeting the requirements after combining and evaluating the mathematical method and the system stacking state. The design method of the application prepares the rapid hardening early-strength concrete which can meet different functional requirements and is suitable for different use conditions from the mechanism itself, and provides design basis for the rapid hardening early-strength concrete material under the composite cementing material system based on the composite cement system.

Inventors

• LI XIANG
• Guo zhijiong
• BU YU
• XU FANG
• TIAN GUIYOU
• WANG JIANAN
• FU WENXIANG
• HU JIANGHAI
• KONG FANSHENG
• Xiong Qiuyang

Assignees

• 湖北武麻高速公路有限公司
• 山东高速湖北发展有限公司
• 中国地质大学（武汉）

Dates

Publication Date

20260505

Application Date

20221202

Claims (6)

1. 1. A design method of a composite cementing material composition of quick-hardening early-strength concrete is characterized by comprising the following steps: selecting each component of a composite cementing material of quick-hardening early-strength concrete, wherein each component comprises a cement component A, a cement component B, silica fume, fly ash microbeads and mineral powder, the cement component A is Portland cement with the strength grade of P.II52.5, the cement component B is sulphoaluminate cement with the strength grade of 42.5, the composite cementing material comprises the following components in percentage by mass, 0.2-0.7 of the cement component A, 0-0.3 of the cement component B and not 0, and the total mass ratio of the cement component A to the cement component B is 0.5-0.7; The molar contents of SiO 2 、Al 2 O 3 , caO and SO 3 contained in the composite cementing material meet the following proportion relationship that SiO 2 :Al 2 O 3 :CaO:SO 3 =0.57-0.83:0.07-0.17:0.52-0.72:0-0.02; The method comprises the steps of taking the content of each component as independent variable, designing the proportion of each component in each group of experiments based on a D-optimal design principle, adopting a response surface design method, taking the compressive strength Y1 on the 1 st day and the compressive strength Y2 on the 28 th day of the net paste made of the composite cementing material as independent variables respectively, respectively establishing mathematical relations between Y1 and the content of each component and between Y2 and the content of each component for each group of experimental data, carrying out polynomial fitting regression to obtain a mathematical model about the composition design of the composite cementing material, and carrying out mathematical evaluation on the mathematical model; The design principle of the D-optimal is as follows: constructing an information matrix M, wherein M=F T (x) F (x), so that the determinant of the information matrix M is maximized, and F (x) meeting the condition is obtained; Wherein F (x) = ; Wherein x 1 ,x 2 ,…,x N represents 1,2, respectively, group N tests, f m (x N ) represents the content of the m-th of said components in said composite cementitious material in group N tests; setting target content ranges, target compressive strength Y1 and target compressive strength Y2 of the components, solving the content of each component meeting the requirements by using the mathematical model meeting the mathematical evaluation conditions, and evaluating the system stacking state of a system meeting the requirements, wherein a specific evaluation model is an MAA model, and the expression of the MAA model is as follows: ; Wherein, when the particle size of P (D) is D, the cumulative screen residue percentage in the system is D max , D min is the maximum particle size, q is the distribution modulus, and the value is 0.23.
2. 2. The method for designing a composite cementing material composition of quick-hardening early-strength concrete according to claim 1, wherein the mineral powder is not lower than grade S105, the specific surface area is not lower than 500 m 2 /kg, the activity index of 7 d is not lower than 95%, and the activity index of 28 d is not lower than 105%.
3. 3. The method for designing the composite cementing material composition of the rapid hardening early-strength concrete according to claim 2, wherein the mass content of SiO 2 of the silica fume is not less than 98%, the specific surface area is not less than 15500 m 2 /kg, the activity index of 28 d is not less than 100%, the loss on ignition of fly ash microbeads is not more than 5%, the water demand ratio is not more than 90%, the volume ratio of spherical particles is not less than 95%, and the activity index of 28 d is not less than 140% of the mineral powder is of grade S140.
4. 4. The method for designing the composite cementing material composition of the rapid hardening early-strength concrete according to claim 1, wherein the composite cementing material further comprises the following components, by mass, 0.1-0.2 of silica fume, 0.1-0.2 of fly ash microbeads and 0.03-0.2 of mineral powder; the mathematical model is as follows: Y1=7.32449A-130.985B-432.351C+753.024D-211.931E+337.515AB+658.449AC-1066.3AD+201.289AE+1036.36BC-966.881BD+361.133BE-623.808CD+1027.07CE-578.778DE; Y2=198.088A-81.8649B+1345.02C+1020.64D+106.583E+293.373AB-2083.06AC-1440.75AD-147.007AE-1838.27BC-1242.74BD+93.6159BE-2774.53CD-1297.46CE-1314.97DE; Wherein A is the mass proportion content of the cement component A, B is the mass proportion content of the cement component B, C is the mass proportion content of the silica fume, D is the mass proportion content of the fly ash microbeads, E is the mass proportion content of the mineral powder, Y1 is the compressive strength on the 1 st day, and Y2 is the compressive strength on the 28 th day.
5. 5. The method for designing a composite cementitious material composition of quick-hardening early-strength concrete according to claim 1, wherein the paste is prepared by the following method: weighing each component according to the D-optimal design principle; Dry-mixing the components; adding water and a water reducing agent into the mixture after dry mixing, and carrying out wet mixing; And (3) filling the slurry after wet mixing, vibrating, curing the film, removing the mold, and finally carrying out standard curing or steam curing to a specified age to obtain the clean slurry.
6. 6. The method for designing a composite cementitious material composition of early-strength concrete according to any one of claims 1 to 5, wherein the response surface Design method is designed with assistance by any one of Design-Expert, minitab, JMP software.

Description

Design method of composite cementing material composition of rapid hardening early-strength concrete Technical Field The application belongs to the technical field of building materials, and particularly relates to a design method of a composite cementing material composition of quick-hardening early-strength concrete. Background While highway bridge construction, along with the increase of different situations such as vehicle tonnage, vehicle flow, even overrun overload, highway bridge is more required to pay attention to road maintenance. The full-scale analysis and investigation on highway bridge diseases show that concrete members such as bridge expansion joints, bridge hollow slabs and bridge head butt strap become the most easily damaged parts in highway bridge structures. Because of repeated impact of vehicle tonnage, vehicle flow and vehicle load on the highway bridge and erosion of external environment, the service lives of concrete members such as bridge expansion joints, bridge hollow slabs, bridge head access slabs and the like are far lower than the design life of the highway bridge. At present, the type of bridge expansion joint transition area concrete commonly used in engineering mainly comprises steel fiber concrete. The steel fiber concrete is a novel composite material formed by mixing short steel fibers distributed in a random direction into common concrete. The steel fibers distributed in a disordered way can effectively inhibit the expansion of concrete microcracks and the formation of macroscopic cracks, and the tensile, bending, impact and fatigue resistance of the concrete are obviously improved. Although steel fiber concrete has become the mainstream choice of concrete in the bridge expansion joint transition area at present because of its superior tensile, bending resistance, impact resistance and fatigue resistance, its range of application is the widest, and the application proportion is the biggest, but because the not enough of early performance, in expansion joint transition area repair maintenance process, not only easily cause the waste of traffic resource, still to a certain extent to expansion joint transition area concrete repair maintenance's effect adverse effect. Therefore, in the repair and maintenance process of the highway bridge, the concrete preferably meets the characteristics of quick hardening and early strength, so that the waste of traffic resources and the adverse effects during repair and maintenance can be avoided as much as possible. In recent years, related scholars propose a quick-hardening early-strength concrete for repairing, for example, an authority bulletin No. CN 103360001B is based on 525 early-strength silicate cement, and a liquid KDSP-1 type composite additive is introduced, so that the quick-hardening early-strength concrete for repairing is prepared. The cement adopted by the invention is single in type and cannot be well blended and designed according to actual working conditions, and the invention is only used for cement concrete pavement and has no popularization value. In general, the rapid hardening early strength concrete under a single cement system has certain use limitation, silicate cement is a main cementing material for preparing concrete at present, the production resource and energy consumption are large, the environmental pollution is serious, the continuous rising of the cement price also leads to the remarkable increase of the concrete cost, and from the aspects of energy conservation, environmental protection and cost saving, the need of searching for a more suitable cementing material is urgent. As a low-energy consumption cement, the sulphoaluminate cement not only has low carbon dioxide emission in the production process, but also has the advantages of high early strength, rapid strength development, corrosion resistance and the like, and is widely paid attention to the industry. In recent years, related scholars propose a composite cementing material based on sulphoaluminate cement-silicate cement, for example, the composite cementing material adopted by the authority bulletin No. CN 105884239A is based on sulphoaluminate cement, a proper amount of silicate cement is introduced, and aiming at a sulphoaluminate cement-silicate cement composite system, a prepared additive is introduced to modify the sulphoaluminate cement-silicate cement composite system, so that the sulphoaluminate cement-silicate cement-based rapid hardening early-strength concrete is realized. The invention does not provide a composition design method for the composite cementing material, and the invention aims at providing an additive of a sulphoaluminate cement-silicate cement composite system, on which quick hardening early strength concrete is realized, so that the invention has no popularization value. Under the rapid development of traffic, the traffic volume is increased, and meanwhile, the bridge is easy to damage except the expansion joint d