Cui Ying, Tan Zhongsheng
School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China.
Key Laboratory for Urban Underground Engineering of Ministry of Education, Beijing Jiaotong University, Beijing 100044, China.
Materials (Basel). 2021 Mar 11;14(6):1362. doi: 10.3390/ma14061362.
Shield construction discharges a large amount of soil and muck. The utilization of discharged soil of shield always has high energy consumption and a low utilization rate. Meanwhile, synchronous grouting is a key process for shield tunneling. The current studies show that the synchronous grouting materials applied now generally have the problem of mismatching among filling property, fluidity, and consolidation strength. In order to study the feasibility of using the excavated soil produced by shield construction in clay stratum as synchronous grouting material, high performance synchronous grouting material was studied by taking red clay as an example, modified by epoxy resin. The fluidity, stability, and strength were measured to evaluate performance of the grout. Material test results show that the addition of waterborne epoxy resin decreases density, improves the stability, the rate of stone, and the toughness of the grouting concretion. Finally, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) were measured to analyze the cementitious mechanism of the grout, test results demonstrated that cement hydration and curing reaction of epoxy resin happened in the grout, the formed polymer film filled the voids in the mixture and effectively bound cement hydration gel and clay particles together.
盾构施工会排出大量渣土。盾构渣土的利用一直存在能耗高、利用率低的问题。同时，同步注浆是盾构法隧道施工的关键工序。目前的研究表明，现有的同步注浆材料普遍存在填充性、流动性和固结强度不匹配的问题。为了研究黏土盾构渣土作为同步注浆材料的可行性，以红黏土为例，采用环氧树脂对其进行改性，研究高性能同步注浆材料。通过测定浆液的流动性、稳定性和强度来评价其性能。材料试验结果表明，添加水性环氧树脂降低了浆液密度，提高了浆液的稳定性、结石率和韧性。最后，通过X射线衍射（XRD）和扫描电子显微镜（SEM）分析了浆液的胶凝机理，试验结果表明，浆液中发生了水泥水化和环氧树脂固化反应，形成的聚合物膜填充了混合物中的孔隙，并有效地将水泥水化凝胶和黏土颗粒粘结在一起。
