Facial support in slurry shield tunneling is provided by slurry pressure to balance the external earth and water pressure. Hydraulic fracturing may occur and cause a significant decrease in the support pressure if the slurry pressure exceeds the threshold of the soil or rock material, resulting in a serious face collapse accident. Preventing the occurrence of hydraulic fracturing in a slurry shield requires investigating the effects of related influencing factors on the hydraulic fracturing pressure and fracture pattern. In this study, a hydraulic fracturing apparatus was developed to test the slurry-induced fracturing of cohesive soil. The effects of different sample parameters and loading conditions, including types of holes, unconfined compressive strength, slurry viscosity, and axial and circumferential loads, on the fracturing pressure and fracture dip were examined. The results indicate that the fracture dip is mainly affected by the deviator stress. The fracturing pressure increases linearly with the increase in the circumferential pressure, but it is almost independent of the axial pressure. The unconfined compressive strength of soil can reflect its ability to resist fracturing failure. The fracturing pressure increases with an increase in the unconfined compressive strength as well as the slurry viscosity. Based on the test results, an empirical approach was proposed to estimate the fracturing pressure of the soil.

泥浆压力为泥浆盾构隧道掘进提供了面部支撑，以平衡外部土压力和水压力。如果泥浆压力超过土壤或岩石材料的阈值，则可能发生水力压裂并导致支撑压力显着下降，从而导致严重的工作面坍塌事故。为了防止在泥浆护罩中发生水力压裂，需要研究相关影响因素对水力压裂压力和裂缝形态的影响。在这项研究中，开发了一种水力压裂设备，以测试黏土的泥浆诱导压裂。不同样品参数和加载条件的影响，包括孔的类型，无限制的抗压强度，浆液粘度以及轴向和周向载荷，检查压裂压力和裂缝倾角。结果表明，裂缝倾角主要受偏应力的影响。压裂压力随周向压力的增加而线性增加，但几乎与轴向压力无关。无限制的土壤抗压强度可以反映其抵抗压裂破坏的能力。压裂压力随无侧限抗压强度和浆液粘度的增加而增加。根据试验结果，提出了一种经验方法来估算土壤的破裂压力。但它几乎与轴向压力无关。无限制的土壤抗压强度可以反映其抵抗压裂破坏的能力。压裂压力随无侧限抗压强度和浆液粘度的增加而增加。根据试验结果，提出了一种经验方法来估算土壤的破裂压力。但它几乎与轴向压力无关。无限制的土壤抗压强度可以反映其抵抗压裂破坏的能力。压裂压力随无侧限抗压强度和浆液粘度的增加而增加。根据试验结果，提出了一种经验方法来估算土壤的破裂压力。