In view of the defects of conventional concrete such as slow setting, long construction period and complex construction, the new idea of slope reinforcement by quick-setting polymer micro anti-slide piles is put forward, and model tests and numerical simulation of sand slope reinforced by quick-setting polymer micro anti-slide piles are carried out. The results show that when the Mohr-Coulomb strength parameter is converted to Drucker-Prager strength parameter in numerical simulation, the value of the Lode angle is set to 0, which can reflect the strength characteristics of the slope soil more accurately. The displacement, deformation development and failure characteristics of the slope under different conditions obtained by numerical simulation are in good agreement with the experimental results, which verifies the accuracy of the numerical simulation to a certain extent. After the 5^th level of horizontal thrust (1500 N), the measured displacement of the slope foot, slope middle and slope top reinforced by a single row of polymer micro anti-slide piles decreased by 33.4%, 33.3% and 33.3%, respectively, compared with that before reinforcement, while the measured displacements of the slope foot, slope middle and slope top reinforced by double-row piles decreased by 55.9%, 53.4% and 43.4%, respectively. Before reinforcement, the slope surface showed wavy deformation characteristics, and the deformation was significantly improved after reinforcement. The pile body in single-row pile condition breaks when the horizontal thrust reaches 1800 N, while the back pile in double-row pile condition breaks first when the horizontal thrust reaches 2400 N. The conclusion of the study verifies the effectiveness and feasibility of fast-setting polymer micro anti-slide piles in slope reinforcement.

Ten cases of ground subsidence in the study area are taken as the research object. Based on field investigations and combined with the geological environment conditions and engineering geological data of the study area, the basic geological background and ground subsidence development conditions of the study area are obtained. Several types of ground subsidence in the study area are comprehensively summarized, and the causes, spatiotemporal distribution characteristics, and collapse formation mechanisms of different types of ground subsidence are analyzed. The finite difference software FLAC3D was used to simulate the development process of ground collapse under tunnel excavation, building houses, groundwater level rise, and heavy rainfall conditions. The formation mechanism of ground collapse in the study area was obtained by analyzing the stress and strain inside the soil layer, as well as the displacement of the surrounding soil and surface of the tunnel. The research results indicate that the construction of residential buildings increases the overlying load, and the rise of groundwater level causes deformation of the soil around the cavern, leading to the expansion of the cavern. Under the influence of seasonal heavy rainfall, the surface undergoes significant settlement.