High Performance Cement-based Grouting Material Mix Design And Performance Study

The high-performance cement-based material is a building material with a wide range of uses and excellent performance.Its ultra-high strength characteristics can change the design ideas of concrete structures,and the characteristics of self-compacting inseparability can facilitate the simplification of construction technology.High-performance cement-based materials have a wide range of applications and developments in the fields of structural design and reinforcement,component connection,construction rapid repair,tunnel grouting,and industrialization of prefabricated buildings.This article mainly focuses on the connection of structural members,and develops the design procedure of mix proportion of high-performance cement-based grouting materials and the study of their performance.This article systematically studies the effects of various types of new mineral admixtures and high-performance admixtures on the cement-based properties of ordinary silicate systems,and compares and selects suitable composite additive component materials for this system.The use of slag and original silica fume mixed with superplasticizer and defoamer build a high fluidity,high strength cement-based system.The use of plastic expand agents and sulphoaluminate expand agents improves the early and mid-term shrinkage problems of cement-based materials in engineering.Using the Alfred model and optimizing the model coefficients,the basic idea of the preliminary design of the cement-based mix desgin was proposed.Using the center mass model and the seepage theory,the final cement-based mix design was determined according to the required material property adjustment,and SEM picture proved that its high-strength features come from design ideas.After obtaining the high-performance cement-based grouting mix design,a steel-reinforced joint experiment was designed,and the application of this material in the connection of the anchoring connection of the grout sleeve and constrained slurry anchor was explored.Research indicates:1.Single-factor experiments show that the slag,fine-grained silica fume,metakaolin,and sulphoaluminate expand agents are suitable for remixing into 52.5ordinary Portland cement,densified silica fume,and fly ash is not suitable as an admixture.Polycarboxylate superplasticizers have the best adaptability to cementitious systems of silicate system.Antifoaming agents and plastic expanders can work together to improve the properties of cementitious materials.2.Using Alfred model to explore the design of high-performance cement-based mix ratio,the model coefficient q should take a smaller value of 0.19 to meet the double requirements of the cement base fluidity and strength.3.Based on the single-factor experimental results,determine the mix proportion of cement-based grouting materials according to the center mass and seepage theory.The obtained grouting material far exceeds the performance of the sleeve grouting material in the?Steel Joint Sleeve Grouting Material??JGT 408-2013?standard requirement.4.The optimized cement-based grouting material can meet the application of rebar in sleeve connection and constrained anchor-anchor connection.According to the experimental results,it is recommended that the steel sleeve connect the anchorage length to 7 times the rebar diameter,constraining the slurry anchor to loosen the anchorage length to 0.7l_aE.The constrained pulp-anchor connection members without the constraint of spiral stirrups have insufficient ability to restrain the concrete and cannot meet the requirements of viscous properties.