The Influence On Strength Caused By Temperature Change Of Super Early High Strength Grouting Material And Strengthening Application

Super early high strength cement-based grouting material is a kind of a mixture composed of cement, fine aggregate, admixture, water reducing agent, retarder, early strength agent, defoaming agent, etc. It is characterized by:having a great mobility after water added, and in a short period of time can produce high strength. It can be used for rapid repair of concrete structures and architecture, secondary grouting equipment foundation,etc. And it also can be used to perfusion of passenger dedicated line pot rubber bearing, perfusion of simply supported box girder bridge bearings and bearing bolt hole. Super early high strength cement-based grouting material has a broad application prospect.Super early high strength grouting material has a better mobility and strength compared with the traditional fine stone concrete. And it is easier to control during the construction. It has better swelling and more convenient construction compared with the traditional epoxy mortar. Since the early 1990s, the independent research and development production of cement grouting material in China, has been widely used in many medium-sized enterprises equipment installation, building structure reinforcement project.The subject chose alumina cement and ordinary Portland cement grout composite system as a cementitious material. Among them, the ordinary Portland cement has hydration reaction under the influence of water, and produces strength and hydration after hardening. After hardening it is bonded with structures to form a unified whole. A lot of incorporation of the ordinary Portland cement can ensure the good durability and the late strength not backwards. The aluminous cement is also an inorganic cementitious materials. In a certain ratio range can improve the early strength and enhances the fire resistance with ordinary Portland cement in. At the same time, the hydration resulting product is more dense after it reacts with ordinary Portland cement.The subject chose anhydrite and hemihydrate gypsum as a bulking agent. The hemihydrate gypsum can improve the early strength of early strength reinforcement materials, and has a micro-expansion function which compensate for material shrinkage during hardening. The anhydrite is used to control the setting time of the cement matrix, so that to ensure sufficient operating time and improve the workability. It also adjusts the amount of cement stone formation of ettringite is moderate. That plays a role in filling the pores without danger of bursting, while providing the late expansion, reducing the probability of cracking. The composite can ensure reasonable dilatability premise. It can provide adequate SO4, and cement hydration generated more compacted hydration products of ettringite.This subject in the study of material test, all test block is filled with polypropylene fibers. Polypropylene fiber is a kind of high strength, small diameter, easy to disperse the grout reinforcement fibers. The join can prevent grouting material burst in such high temperature, improving grout toughness at room temperature environment while reducing cracks in the plastic stage. Part of the test block is filled with the carbon fiber. The carbon fiber at a temperature of 3000? can also maintain a higher residual strength. The cement-based grouting material strength reduced after the earthquake and fire occurred. The carbon fiber provides higher residual bearing capacity.The stress-temperature curve test of super early high strength grouting material is a kind of orthogonal combination test, which combines temperature, aluminous cement and ordinary Portland cement mass ratio, ordinary sand and refractory sand and whether to join the carbon fiber as the parameter changes. Make an observation block of apparent changes before and after high temperature, mass loss and other physical properties, then make an analysis of strength degradation causes to study results of stress-temperature curve and the optimal ratio, PT-C-1:7. The stress-temperature curve fitting formula is drawn,which grouting material in structural testing of foundation.Super early strength grouting material reinforcing beam bending test is a kind of test which optimal ratio PT-C-1.7 and contrast material PT-1:5?PT-C-1:5?PT-C-1:0 is also used as a refractory material applied to the reinforcement of the simply supported beam to contrast the bending performance. The reinforcement of beam damage forms is similar to normal concrete beam, according to observations, recorded cracking load, yield load, ultimate load, span deflection, etc. And after high temperature test the super early high strength cement-based grout can be a good combination with old concrete. It can maintain a high load carrying capacity.