Lixian Fault Characteristics And Analysis Of It’s Effect On Beijing-Gu’an Light Rail Line

Bijing-Gu’an light rail located in the southern tip of Beijing, between JingKai highway and the proposed new airport, is extremely important, so it will be Beijing North-South transportation arteries. If early research on the geological conditions of the deep or lateral fracture is not enough in-depth, there will be much serious safe hidden trouble in the process of the construction and operation. So the solid fracture investigation and activity evaluation become the important content in the research of regional stability of Beijing-Gu’an light rail lines construction. In the process of characteristics research and analysis, we deployed a variety of physic-chemical methods on the basis of the geological survey, drilling data, and find out the fracture position, fracture tendency and direction in the workspace. On the other hand, we will offer reference for next step active fault prospecting of traffic integration important linear engineering in capital economic circle and even Beijing-Tianjin-and-Hebei Region by summing up the experience with Lixian fault exploration.Firstly we collected and organized regional geological data of Beijing-Gu’an light rail line corridor, then in combination with field geological survey and data collection, we have mastered the natural geographical landscape, geological structure, stratum lithology, the basic condition of the seismic profiles of the workspace, We have proven the Lixian fracture position using some methods just like controlled source audio-frequency magneto telluric sounding, microgravity exploration and geophysical-geochemical method of radon gas measurement; the fault is towards south east, and the dip angle is about 75 °; the throw of the hanging wall and footwall blocks is slip in 400 ~ 500 m. This is a normal fault, whose south east disk is updip block, and the north west disk is thrown side; the inclination of the main fracture and the fracture, 500 ~ 800 m apart, is in good agreement. Besides, we analyzed the activity of the Lixian fracture using geological survey, geophysical and geochemical prospecting achievements and borehole core contrast method. We briefly analyzed the influence of the fracture on the Beijing-Gu’an light rail lines according to the position relationship between Lixian fracture and Bing-Gu’an light rail. This research results will provides important basic geological reference for the next step of construction.