Research On The Development And Performance Of Ultra Early Strength Seismic Refractory Reinforcement Materials

With the acceleration of urbanization and the frequent earthquake disaster, the structure of seismic reinforcement becomes more and more important. Reinforcement processes require fast and stable reinforcement materials, to meet the needs structural reinforcement and repair, to ensure structural safety and reliability, thereby ensuring the life and property safety of the people.The purpose of the paper is to provide an ultra-early strength, fire-resistant, fire-resistant super early strong seismic reinforcement material, which has a certain economic and social benefits. It has early strength, high strength, high temperature, mobility and micro-expansion characteristics, and easy construction, stable performance, applicability, can work with traditional concrete coordination.First, the paper has been studied with mixture ratio, including the type and quantity of cementitious material to determine, aggregate gradation, water-cement ratio is determined, admixtures, optimize component, mineral admixtures, fibers, screening and optimization of expansion component; fluidity, compressive strength, flexural strength, free expansion, crack resistance and other parameters to control the mix design and optimization. The system with a variety of admixture using hingh mortar ratio can be prepared for the initial fluidity greater than 325mm,30min fluidity greater than 280mm,2h compressive strength 34.80MPa,24h bending strength over 13.82MPa,28d compressive strength greater than 99.90MPa,28d compressive strength greater than 56d compressive strength; The system of early SEM microstructures showed good crystal growth, structure compact. Secondly, at different temperatures, the authors select the different sand-cement ratio, and test cubes of 150mm×150mm×150mm, and do the high temperature test, and analyse the trend of temperature and the sand-cement ratio on the residual compressive strength, according to the result of high temperature to adjust the mixture ratio. Finally, the authors conducted Drawing test and related performance studies.Through repeated adjustment and test of mixture ratio, the proportion of aluminate cement and ordinary Portland cement for 1:7, the economic benefits of super early strength reinforcement material is good,54.7%residual compressive strength at the 1000? high temperature combustion after 30 minutes, compared to pure calcium aluminate cement, the economic costs significantly reduced, the comprehensive index do best. Block expansion value of 0.2+ 0.05%, is relatively stable. The existence of polypropylene fiber, reduce the wear resistance and impermeability performance of super high early strength seismic refractory reinforcement material,Introducing metakaolin and early strength component, to some extent, improve the age strength reduced, So as to solve the wear resistance and anti permeability reduction problem. The addition of polypropylene fiber can effectively control the generation of cracks, reduce the width of cracks, and improve the crack resistance of the reinforcement materials. With the increase of polypropylene fiber volume content of fiber volume, mass loss rate of the block and strength loss rate decreased, and antifreeze performance meet the requirements. The drawing test results show that, reinforcement material strength and anchorage length are the important factors to affect the average bond strength of steel. Depth of different reinforcement, mainly showing bar pulled out, bar pulled off, bar pulled out at the same time, and the root material eminence, three failure modes. Calculation formula based on the theoretical analysis, provide a reference for later structure test, and provide support for the future practical engineering structural transformation of the old frame reinforcement.