Hydration process and rheological properties of SJP cement paste
摘要
Qwing to that the common cement paste used in the complex soil strata with wide steep seams and loose space cannot fill firmly and run along the gaps, a new type of SJP cement paste is developed, which has great initial fluidity and good groutability. Its apparent viscosity can suddenly increase and its fluidity of the rheological properties can suddenly drop during pumping. The SJP cement paste is made from modified fiber, CaSi early strength agent and cement, with the amount of additive agent of 2%~2.5%. The additives first form the solvent membrane in the surface of cement particles, which can adjust the ion concentration of cement hydration and CaSi cationic. The role of controlling the speed of nucleation at the acceleration stage is achieved. The retardation stage of SJP paste is controlled by the nucleation and diffusion process, and the stable stage is mainly controlled by the effect of diffusion. Because of the high speed of hydration, controllable flowing time and are closely cemented hydration products, the later strength of solidified paste is improved by 15%~25% higher than that of the common cement paste. The SJP paste can solve the problem of higher early strength and lower later strength. So it has got a larger range of popularization and application.