Application Research on Key Problems and Solutions of Micro Top Shield Construction Technology

In the application of micro-shield construction technology in complex strata, there are some problems such as pipe joint lock, seal failure, insufficient jacking force and excessive surface settlement, which seriously affect the construction efficiency and safety. In order to solve the above problems, this paper takes the natural gas high-pressure pipe network project of a city as the research object, and puts forward a set of systematic solutions to improve the construction efficiency, ensure the construction safety, and effectively control the surface settlement. In this paper, through the field data collection and parameter analysis, the mud formula and grouting technology are optimized. At the same time, the phased jacking force control strategy and redundant seal design are introduced, and the dynamic mud pressure control system and settlement monitoring and early warning mechanism are established to achieve fine management and risk control in the construction process. The optimized construction scheme achieved significant results: peak jacking force was reduced by 23%, surface settlement was controlled within 3mm, daily tunneling speed was increased by 75%, and mud consumption was reduced by 33%. These results show that the measures adopted have significant advantages in improving construction efficiency, reducing resource consumption and controlling construction risks. It can be concluded that the phased jacking force control and dynamic mud injection can effectively alleviate the problem of pipe joint lock. The redundant seal design and equipment linkage optimization can ensure the sealing performance of collaborative work, and the dual-liquid grouting process combined with closed-loop pressure control can significantly inhibit the surface settlement. These measures provide reliable technical support for the long-distance construction of complex strata, and have important engineering application value.