The Studies On Friction Characteristics Of Slope Protection Interface In Cold Regions

Due to the effects of cold, freezing and thawing, the friction interface and mechanical properties of the slope structure was changed in cold regions. In cold areas excavation cutting, the new cut slope and embankment construction and other engineering activities, would made the soil under the newly exposed to freezing and thawing in the relevant deformation and stability analysis, we must consider the physical and mechanical properties change. With the construction of hydraulic engineering and road works and other permafrost regions to carry out a wide range of construction, our construction of geotechnical engineering in cold regions would experience the same problem. Currently, the freezing and thawing effects on soil physical properties have been more in-depth research, and freezing and thawing of soil slope structure and interaction with nature under the influence is the lack of systematic research, there is no comprehensive laws proposed to be further depth study. In this paper slope structure of indoor model was studied, the friction interface friction angle (φ) and cohesion (c) are two factors to study change of the friction interface parameters, hinged block of concrete, concrete forms and gravel polyurethane revetment materials effect on change of Cant friction shear strength parameters of cohesive soil at room temperature and after melting circulation.First, in this paper using homemade cant friction apparatus to do cant friction shearing test to study soil water content effect on shearing strength of hinged block of concrete, concrete forms and gravel polyurethane revetment materials at room temperature. Shear strength parameters of different soil water content is given under the effect of three kinds of revetment materials by results, is the specimens cohesion (c) and friction angle (φ). Finally have a qualitative analysis on data by test.Secondly, in order to study of freeze-thaw effects on revetment structure, the paper designs on the indoor clay soil freeze-thaw cycle friction test. Measured by testing hinged block of concrete and concrete prefabricated components materials respectively was under the moisture content is 18% and saturation of cohesive soil, there was a friction meter cant test after the same freezing time and melting time to get shear strength index. The test was got a group of revetment structure shear strength parameters every five times of melting circulation and totally ten times and finally analysis data of test.Test analysis showed that change of the specimens cohesion (c) and friction angle (φ) under different combination of the friction interface parameters, hinged block of concrete, concrete forms and gravel polyurethane revetment materials in normal condition and its cohesive soil was bigger. The mainly showed that the specimens cohesion (c) and friction angle (φ) gets decreases with increase of soil moisture and presents good linear relationship; In the material selection of revetment materials, soil moisture content is a prior consideration. Three kinds of revetment materials can satisfy revetment structure sliding resistance requirement when soil moisture content is less than 20%; and revetment structure is easy to destroy and anti-sliding ability obviously decreases when soil moisture is more than 22%. The ability of hinged block of concrete is better than other two materials, so it is prior to choose hinged block of concrete when designing revetment structure; the specimens cohesion (c) and friction angle (φ) of three kinds of revetment materials decreases with increase of freeze-thaw cycle times after multiple freeze-thaw cycle. The soil moisture content occur migration, surface enrichment increase, 5cm, 15cm, 25cm layer soil has different degree of water loss. Especially Shallow soil migration is quite obvious, deep change faint. Main reasons that affect stability of revetment structure is soil moisture content occurring migration. Consider as soil moisture content and the soil type beside revetment materials when designing revetment structure although at present the only under specific conditions obtained the experimental conclusion, the subsequent cold the stability of revetment structure the indoor experiment provides useful reference.The author hopes that numerical analysis of laboratory experiments to provide technical support for future construction of slope protection structures.