A Study on the Status of Technology for Express-way Tunnel Construction and Existing Problems
Summary: The article aims at the current situation of the rapid development of Guangxi highway tunnels, introducing the main technology like survey, designing construction and testing used in Guangxi tunnel construction. It had practical significance in giving ideas on several outstanding problems in tunnel construction
Key Words: road tunnel; design; construction; measures
Guangxi highway construction has a history of nearly 15 years, having made great progress in the tunnel engineering technology. On the one hand, the scale of construction is increasing. By the end of 2006 expressway tunnels had been completed, the cumulative length was 1,785,000 linear meters. 23 tunnels are under construction, cumulative length is 31,186,000 linear meters. It is planned to build 55 units, cumulative length is 72,160,000 linear meters. At the same time，the road tunnel section types are diversified. On the other hand, highway tunnel construction technology has improved significantly. Relying on the long tunnel construction technology and operation management monitoring technology of Pingle-Zhongshan expressway Muchong tunnel are the shallow buried bias construction technology. TSD geological advanced forecasting technology, highway karts tunnel construction technology, tunnel disaster prevention technology, ventilation and lighting technology. These technical achievements have strongly supported the Guangxi Expressway tunnel construction. These articles summarize the status of Guangxi Expressway tunnel construction technology and do some discussion of main problems.
- Current Status of Guangxi Expressway Tunnel Construction Technology
According to the tunnel survey and structural design, this paper introduces construction technology, quality inspection and other aspects in Guangxi Expressway tunnel construction technology.
1.1 Status of Tunnel Survey and Measurement Technology
Highway tunnel engineering survey and measurement generally use aerial photogrammetric, and draw a 1:2000 scale digital terrain map. In the identified route corridor zone, investigate the natural conditions of the area. Reconstruct the engineering geology and hydrogeology, survey terrain, elevation, traverse, measures the tunnel roof line, survey construction program and budget information according to the route.
At present, Guangxi tunnel engineering geological survey is mainly based on detailed geological survey, using geological mapping, drilling, geophysical exploration, indoor geotechnical test, water pressure test and other surveying methods. Geophysical prospecting uses geological radar, shallow seismic, high-density resistivity and other geophysical methods. The geological radar use the united states GSS company Sir-2 type equipment, high-density resistivity method using the technology produced by WDJD-2 type multi-function digital DC exciter. Shallow seismic used Beijing Institute of Geophysical Prospecting SWS-1G multi-function surface wave instrument produced by Beijing Institute. Tunnel engineering field measurement generally use GPS for terrain control and wire measurement, data acquisition GPS, total station and automatic Aping level and other equipments.
1.2 Current status of tunnel engineering design technology
