Research On Early Strength Agent Of TSN Concrete Composite And Its Application In Rescue Engineering

The rescue project is of timeliness, which requires the concrete to reach the specified strength in a short time. Early strength of concrete, it can speed up the progress of the construction, to prevent the expansion of the impact of disasters or reduce, eliminate the impact of disasters. The fast hardening cement can achieve rapid setting and hardening,improving the early strength of concrete, but the cost is higher; in ordinary portland cement,early strength agent, can improve the workability of concrete, and improve the early strength of concrete, to meet the needs of emergency rescue.This paper analyzes the advantages and disadvantages of different varieties of early strength agent, and draws a conclusion that the concrete engineering should be limited using chloride salts early strength agent, not using silicate series of early strength agent, is not recommended to use lithium salts early strength agent of conclusion; the development trend of early strength agent is compound early strength agent instead of single group divided into early strength agent.The resistivity of cement slurry to determine the composition of compound early strength agent triethanolamine(T), sodium sulfate(s) and nitrite sodium(n),and named for TSN compound early strength agent. To study the mechanism of early strong action of three kinds of early strength agents, the hydration reaction rate of three calcium silicate and calcium silicate two was analyzed, and the key to shorten the period of cement hydration reaction was analyzed.Through the orthogonal design, the difficulty of data processing is simplified, and the ratio of the three components is determined. Through the test of indoor test project, the composite early strength agent can reduce water consumption, reduce cement setting time,improve the early strength of concrete, and have good adaptability to the early strength of concrete. Application of the tunnel collapse in the project, concrete and easy, high early strength.The research results of this paper:(1)Compound early strength agent ratio: triethanolamine(T) 1.3%(S 65.8%), sodium sulfate, sodium nitrite(N) 32.9%;(2)In the case of 1.52%, the flow of concrete is the best, and the concrete strength is the highest;(3)The early strength of concrete is obvious, and the strength of 1d age is 50%, and the strength of 3d is 80%;(4)The bond strength of the surrounding rock is higher than that of other concrete and the bond strength of the surrounding rock is lower than that of ordinary concrete.