SJP注浆浆液水化进程与流变特性研究

针对陡倾宽缝、松散架空等复杂地层灌浆,普通水泥浆存在"灌不住"、"顺缝跑"等问题,研制开发的SJP水泥基灌浆材料具有初始流动度大、可灌性好,接近可泵期时表现为黏度突增、流动度突降的流变特性。SJP浆材是水泥基浆材掺加改性纤维、硅钙早强剂与稳定剂配制而成,助剂加量为2%~2.5%。掺入水泥浆中的助剂首先在水泥颗粒表面形成溶剂膜,起到调节水泥水化离子与助剂硅钙阳离子浓度变化的作用,实现水化加速期控制成核的速度,最后掺入的稳定剂可以调整水泥水化衰减期的成核和扩散,调节水泥浆的流动时间。SJP浆材由于水化速度快,流动时间可控,水化产物凝结胶连紧密,结石体后期强度较普通水泥浆平均提高15%~25%,解决了水泥基速凝浆材早期强度高后期强度低的问题,得到了较大范围的推广应用。

Hydration process and rheological properties of SJP cement paste

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.