基于骨架构建药剂真空预压法加固超软土试验

针对温州某工程中的高含水率超软土，通过添加不同药剂结合真空预压开展模型桶试验，对真空度、排水速率和含水率进行测试；选取工程实际中可行性较高的药剂开展模型池现场试验，探究不同药剂对土颗粒粒径及渗透性的影响.从两种试验可以得到如下结论：1）模型试验中，经固化剂或絮凝剂+固化剂结合真空预压处理废浆可以获得较好的加固效果.2）加入固化剂能够快速改变土体的界限含水率和抗压性能，通过胶结力生成骨架结构而增加了超软土渗透性，使真空排水阶段含水率降低120%.3）絮凝剂通过长链“架桥”吸附土颗粒生成链状体，絮凝脱水效果好，絮体含水率直接降低80%，但在真空阶段时渗透性较差，排水速率较慢；絮凝剂和固化剂组合添加不仅可以得到好的絮凝效果，而且由于固化剂的骨架构建作用使其在真空预压阶段具有良好的渗透特性.研究表明，基于骨架构建的药剂真空预压法加固超软土的效果十分显著.

Experimental study on ultra-soft soil reinforced by vacuum preloading with flocculation based on skeleton construction

The tests were conducted by adding different chemicals and vacuum preloading aiming at the ultra-soft soil in a project in Wenzhou. The vacuum degree, drainage rate and moisture content were tested. Then the high feasibility of the agent was selected to conduct the model pool field test. The effects of different agents on the particle size and permeability of soil particles were analyzed. 1) In the model test, it is possible to obtain a better effect on the treatment of waste slurry by curing agent or flocculant+curing agent combined with vacuum preloading. 2) The addition of curing agent can quickly change the limit water content and compressive properties of the soil. The skeleton structure can be formed by the cementation force, thus increasing the permeability, and the moisture content of the vacuum drainage stage can be reduced by 120%. 3) Flocculant uses long chain bridging adsorption of soil particles to form a chain like body and obtain good effect of flocculation dewatering. In the process of sedimentation, water mass fraction decreases 80%. Under vacuum load, the permeability is low and the drainage rate is slow. The combination of flocculant and curing agent not only can get good flocculation effect, but also has good permeability in the vacuum preloading stage due to the structure of the curing agent. Results show that the vacuum preloading method based on skeleton builders is very effective in the treatment of super soft soil.