Influence factors and calculation model of the adhesion strength of clayey soil for EPB shield tunnelling

作     者：Shuying Wang Pengfei Liu Jiazheng Zhong Zhunlin Ni Tongming Qu 

作者机构：School of Civil EngineeringCentral South UniversityChangsha 410075HunanChina CCCC Second Harbor Engineering Company Ltd.Wuhan 430012HubeiChina Institute of Rock and Soil MechanicsChinese Academy of ScienceWuhan 430061HubeiChina Zienkiewicz Centre for Computational EngineeringCollege of EngineeringSwansea UniversitySwansea SA18EPWalesUK. 

出 版 物：《Transportation Safety and Environment》 (交通安全与环境（英文）)

年 卷 期：2022年第4卷第3期

页      面：55-64页

核心收录：

学科分类：081406[工学-桥梁与隧道工程] 08[工学] 0814[工学-土木工程] 082301[工学-道路与铁道工程] 0823[工学-交通运输工程] 

基　　金：the National Natural Science Foundation of China(Grant Nos.52022112 and 51778637)are acknowl-edged and appreciated 

主　　题：Earth pressure balance(EPB)shield clayey soil adhesion strength grey theory 

摘      要：When earth pressure balance (EPB) shield tunnels are constructed through clayey ground, the soil adheres to the cutter, cutterheadand chamber bulkhead due to the high adhesion strength between the steel and the clay, thus clogging the shield. To investigatethe influence of different factors on the adhesion strength, this study used montmorillonite, kaolin and mixtures of the two as testsoils. The adhesion strength between the steel and clay is determined with a customized rotary shear apparatus. The results showthat when the consistency index of the soil specimen is less than 1, the adhesion strength between the steel and clay increaseswith the consistency index. As the consistency index decreases, the effect of the normal pressure on the adhesion strength graduallyweakened. As the contact angle of the shear plate increases, thus reducing the hydrophilicity, the adhesion strength decreases. Whenthe soil specimens with different plasticity index values have the same consistency index value, the adhesion strengths are *** adhesion strength increases gradually with increasing surface roughness. Based on grey incidence analysis, the order of thefactors affecting the adhesion strength is as follows: normal pressure consistency index contact angle plasticity index ≈ surfaceroughness. The normal pressure, consistency index and contact angle all have important effects on the adhesion strength betweensteel and clay. However, because there are no large differences in the contact angle among the metal materials, the approximateadhesion strength can be calculated by considering the effects of only the normal pressure and consistency index. Themeasures thatare effective for preventing EPB shield clogging are increasing the soil softness and decreasing the hydrophilicity of the cutterheadby applying new materials for the cutters and cutterhead.