The Deformation Of Analysis And Research Of Soil Nailing In Highway Slope

Soil nailing is a new technique to be used in excavation of soil and slope stability ,which is developed from abroad in last two decades years. With the rapid development of construction of highway, the stability of high and steep manual work slope is concerned. In many means in deal with slope stability and enforcement, soil nailing with simple technology, low cost and short duration of construction, so it is used abroad in cut slope. However, not only the working mechanism and design methods of the soiling nailing but also engineering practice are not well known and further studies need to be made, the theory of soil nailing is behind the application, especially the research of deformation of soil nailing is very limited.In this paper, based on a lot of documents and data, mechanism and performance of soiling nailing and the theory of non-saturated soil are discussed and analyzed in detail. The nails head displacement is analyzed based on the two aspects that is gradually load and circularly load. Then analysis of the bond strength between soil nails and soil applying mechanics model of pull-out tests and model test result and numerical value simulation. Based on many pull-out tests in Lei-Yi expressway cut slopes, the rule is drawn that length of soil nails and limit interface bond strength is varied inverse ratio, and that making a amendment to interface bond strength in design.This paper analyzes influence factors and deformation characters of highway slope soil nailing. The test results show that the strength of non-saturated soil are affected by water content of non-saturated soil. The character and principle of FLAC-3D (Fast Lagrangian Analysis of Continuain 3 Dimensions ) are described simply. Then numerical simulations are dealt with the following content: No.1 soils nailing wall on CLOUTERRE project in France; based on Lei-Yi expressway K270+980~K271+240 sect soils, horizontal displacement δh and δh/H are analyzed in slope utmost height under vary ratio of slope, in grade and monopole slope in same ratio of slope, original design and alteration design are analyzed by representative K271+180, water content vary affect on the deformation of soil. The results and conclusions are helpful and valuable for soil nailing.