Based on a deep pit project in Jinan, which is adjacent to a high-speed railway and situated on a gravel aquifer, this paper conducts a comparative experiment between “with MJS horizontal bottom sealing” and “without bottom sealing”, synchronously monitoring the water inflow, the drawdown of the water level outside the pit, and the recovery rate of the water level inside the pit. The comparison results confirm that the permeability coefficient of the MJS bottom sealing section decreases from 1.2×10−1 m/d to 1.1×10−3 cm/s, the drainage volume of the foundation pit reduces by 99%, and the fluctuation of the water level outside the pit is less than 1/30 of that in the unsealed section. This method achieves deep space excavation with “micro-dewatering and zero spring loss”, providing a reproducible and scalable example for underground space development under the condition of spring preservation in Jinan.
Yang et al. (Thu,) studied this question.