Abstract
In recent years, with the undergrounding and intensification of municipal utility facilities, pipe jacking construction has been increasingly widely applied. This paper takes the Shenzhen Metro Line 16 co-constructed utility tunnel project as an example to elaborate on pipe jacking machine construction technology and its application (including various parameters of the pipe jacking machine, construction preparation, construction process, project effectiveness, etc.); combined with the specific engineering geological conditions of high water-saturated sand-cobble strata, it analyzes in detail the impacts on the project such as poor stratum stability, uneven distribution of sand and cobbles, and high phreatic water level during flood seasons. Through the adoption of corresponding targeted measures including equipment adaptation, slurry modification, and construction process control, it effectively solved problems that frequently occurred during the jacking process, including pipe jacking axis deviation, riverbed settlement, disturbance of overlying pipelines, and difficulty in clearing blockages in slurry discharge pipes and slurry pumps, thereby demonstrating that pipe jacking construction is also feasible in high-water-pressure sand layers and cobble layers. Pipe jacking construction technology possesses advantages in municipal pipeline network construction such as construction safety, rapid construction speed, and minimal impact on the ground environment, can effectively control ground settlement, ensure construction safety, and improve the utilization efficiency of urban space.
Full Text
Preamble
A Brief Discussion on Slurry Balance Pipe Jacking Construction Technology in Sand-Gravel Strata
Zeng Lingjian
Guangzhou Metro Engineering Consulting Co., Ltd., Guangzhou 510000, China
Abstract: In recent years, as municipal public utilities have been increasingly placed underground and consolidated, pipe jacking construction has been more widely applied. This paper, using the Shenzhen Metro Line 16 shared utility tunnel project as a case study, elaborates on pipe jacking machine construction technology and its application (including various parameters of the pipe jacking machine, construction preparation, construction process, and project outcomes). Combined with the specific engineering geological conditions of a high-water-content sand-gravel stratum, it provides a detailed analysis of the impacts on the project from factors such as poor stratum stability, uneven distribution of sand and gravel, and high shallow groundwater levels during flood seasons. Through the adoption of targeted equipment modifications, improved slurry formulations, and construction process controls, it effectively resolves common issues during jacking operations such as pipe axis deviation, riverbed settlement, disturbance of overlying pipelines, and difficult-to-clear blockages in slurry discharge pipes and pumps, thereby demonstrating that pipe jacking construction is also feasible in high-water-pressure sand and gravel layers. Pipe jacking technology offers significant advantages in municipal pipeline network construction, including enhanced construction safety, rapid construction speed, minimal impact on the ground surface environment, effective ground settlement control, and improved urban space utilization.
Keywords: sand-gravel strata; circular pipe jacking; construction measures