Study On Gravity Erosion And The Engineering Influences For Yalu Freeway Wenwupo Lamaxigou

In the planning and construction of Ya'an～Shimian～Lugu highway is the key project of western China's current construction, which is a four-lane highway all standards and the design speed of 80 km/h. The topographical and geologic conditions are very complicated. The Lamaxigou Wenwupo Xigeda-stratum is poor nature of engineering geology. A number of gullies were formed in the slope long-term water erosion. The gully has a longitudinal profile cutting depth of 30 to 40 m. It is a loose and poor stability in the side of the gully. It cuts easily instability in the process of erosion under the bed in the ditch. And there is a yearly to the groove and the first expansion of cross-strait ditch. Gravity erosion is very serious, directly impacting on Yalu construction and normal operation.In this paper, firstly it analyses the formation of gravity erosion under the geological environment background of the Lamaxigou Wenwupo. Mainly from the topography, lithology, regional geology, geological structure, meteorology, hydrology, earthquakes, and human activities such as eight aspects of the investigation and analysis which dominate gravity erosion of the Lamaxigou were ascertained. It provided a scientific basis to the area of harnessing gravity erosion.From research on the characteristics of distribution and development gravity erosion of, the main models of gravity erosion launched in the region as follows: attenuation-strength, cutting-erosion, landslide-block and drag-goude. A detailed analysis carried out in two angels between mechanical mechanism and numerical simulation.The paper identified the connection with different types of erosion by an analysis of the disaster chain of the Lamaxigou. Different types of gravity erosion are rather interaction and mutual restraint than isolation such as landslide, collapse, debris flow and so on. It provides corresponding basis traceability management and control measures for gravity erosion of the Lamaxigou Wenwupo.Finally, it proposed the principle of rectification to the gravity erosion of the Lamaxigou. Gravity erosion occurred in the valley slope, the runoff water between the ditch and gully erosion is a very close relationship. It is a complete system. Starting from the entire watershed system, it carried out between groove, the bottom of the valley slope and comprehensive management. The paper suggests constructing sediment control dam locking, anti-filling pressure and the construction of drains and other measures on both sides under this principle. And an analysis of the treatment stability and deposition of valley raceway slope of gravity for the erosion of the Lamaxigou. It provides comprehensive management of a complete set of ideas.