CONTROL STANDARDS FOR SETTLEMENT OF GROUND SURFACE WITH EXISTING STRUCTURES DUE TO UNDERGROUND CONSTRUCTION OF CROSSING TUNNELS

Ground settlements due to construction of underground tunnels crossing existing structures are an important issue. It is often encountered in the development of underground traffic and high speed railways lines. This paper investigates the ground settlement standards and methods caused by tunnel excavation. According to the different characteristics of roads,railways,tunnels and buildings,and including different construction characteristics,excavation areas,depths and engineering geological conditions,different existing structures have different control measures and recommended standards.So,the current standards of ground settlements are unreasonable in tunnels crossing,because the characteristics of the existing structure,geological conditions and construction features may not be taken into account in the ground settlement standards.