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In this paper, the finite element (FE) model of the three-dimensional (3-D) transient thermo-stress field of a brake shoe was established and then the software ANSYS 13.0 was used to get the numerical solutions; an experiment was carried out on the X-DM friction tester to verify the FE model. It was found that both the whole temperature and the equivalent stresses of the brake shoe increased and then decreased during mine hoist emergency braking; region of 1 to 3 mm below the friction surface was suffered to larger temperature gradients and stresses.

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Compared to the traditional anchor cable, the constant resistance and large deformation anchor cable (constant resistance and large deformation anchor cable) has good applications in many fields of geotechnical engineering. Through the indoor static tension test, this study reveals the variation law of constant resistance, axial strain, the outer diameter of the sleeve, and the thermal effect of constant resistance and large deformation anchor cables during static tension. The ANSYS software was used for the first time to establish the nonlinear thermomechanical coupling analysis model of the finite element structure of constant resistance and large deformation anchor cables for the numerical calculation and analysis of static tension mechanical properties of constant resistance anchor cables. The experimental results that the average elongation of this batch of constant resistance anchor cables is 905 mm with an average elongation rate of 45.2% and an average constant resistance of 650 kN prove that constant resistance anchor cables are characterized by good constant resistance and large deformation, which can meet the requirements of deep soft rock roadway support and advanced landslide monitoring. The numerical simulation results show that the elongation of this type of anchor cables is 902 mm with an elongation rate of 45.1% and a constant resistance of 660 kN, which are basically consistent with the experimental results, indicating that numerical simulation is relatively accurate for testing the mechanical property of constant resistance and large deformation anchor cables, and the combination of the indoor test and numerical simulation provides the reference for engineering practice and design optimization of constant resistance and large deformation anchor cables.

Water is one of the major risk sources in the excavation of deep-large foundation pits in a water-rich area. The presence of intrusive broken diorite porphyrite in the stratum aggravates the risk level of deep foundation pits. Based on a geological survey report and design documents of parameter information, MIDAS/GTS software was used to perform the numerical simulation of an engineering example of a deep foundation pit project of ultradeep and water-rich intrusion into the broken rock station of subway line 4 in a city. The simulation results show the characteristics of seepage path evolution, seepage aggregation areas and points, and the effect of seepage on the deformation of a deep foundation pit during the whole construction of this deep foundation pit. The results show that with the precipitation-excavation of the deep foundation pit, the pore water pressure at the bottom of the foundation pit follows a distribution of three “concave” shapes. High-permeability pressure zones are found around the foundation pit, intruding broken diorite porphyrite zones, and middle coarse sand zones. With further excavation of the foundation pit, the seepage pressure in the middle part of the foundation pit gradually decreases, and the two “concave” distributions in the middle gradually merge together. After excavation to the bottom of the pit, the pore water pressure at the bottom is distributed in two asymmetrical “concave” shapes, and the maximum peak of pore water pressure is found at the intrusion of fractured porphyrites prone to water inrush. The four corners of the foundation pit are prone to form seepage accumulation zones; therefore, suffosion and piping zones are formed. The surface settlement caused by excavation is found to be the largest along the longitudinal axis of the deep foundation pit, whereas the largest deformation is found near the foundation pit side in the horizontal axis direction of the foundation pit. With the excavation of the deep foundation pit, the diaphragm wall converges to the foundation pit with the maximum deformation reaching about 25 mm. After the first precipitation-excavation of the deep foundation pit to the silty clay and the bottom of the pit with the largest uplift, with further precipitation-excavation of the deep foundation pit, the uplift at the bottom of the deep foundation pit changes only slightly.