盾构泥浆絮凝-固化联合作用试验研究及宏细观探析

为解决目前盾构泥浆（经泥砂分离）资源化利用率低的问题，开展絮凝-压滤-固化试验和絮凝-固化试验，进行泥浆脱水性能、流动度、固化体无侧限抗压强度等宏观性能测试和SEM（scanning electron microscopy）、CT（computed tomography）扫描等细观性能测试，探究絮凝-固化联合作用下盾构泥浆高效建材化利用和流动化填料利用的可行性。研究结果表明： 1）絮凝-压滤-固化试验中，采用絮凝-固化剂处理的泥浆脱水速率最快，说明固化作用对泥浆脱水性能有促进作用； 2）高压挤压下硅酸盐水泥基絮凝-固化体可大幅脱出水分，固化体3 d无侧限抗压强度达2 MPa左右，具有建材化应用的潜力； 3）絮凝-固化试验中，采用硫铝酸盐水泥基絮凝-固化剂处理后的泥浆流动度在20~30 cm，3 d无侧限抗压强度最高可达130 kPa以上，具有流动化填料应用的潜力； 4）细观形貌测试结果表明，絮凝-固化剂的絮凝作用与固化作用可相互促进，提高固化体的强度。

Macro and Micro Coupling Effect of Flocculation Solidification of Waste Shield Slurry

Presently, resource utilization efficiency of waste shield slurry is low. Hence, a series of macro and micro scale tests (dehydration performance, fluidity, unconfined compressive strength, scanning electron microscopy, and computed tomography scan) on waste shield slurry by adding flocculation solidification agents are conducted to investigate the possibility of resource utilization of waste slurry. The results show the following: (1) The slurry has a higher dehydration rate after the addition of flocculation solidification agents, indicating that solidifaction promotes slurry dehydration performance. (2) Treated by ordinary Portland cement based flocculation solidification agent, the moisture content of solidified soil can be greatly reduced under high pressure extrusion, and the unconfined compressive strength after three day curing becomes greater than 2 MPa, indicating the potential as building materials. (3) The slurry treated by sulphoaluminate cement based flocculation solidification agent can be applicable as controlled low strength materials with fluidity ranging from 20 to 30 cm and the three day undefined compressive strength becoming more than 130 kPa, indicating the potential as fluidity filling materials. The micro test shows mutual improvement of flocculation and solidification.