《土工格栅界面摩擦特性试验研究》.pdfVIP

TU411 A2006 0座机电话号码 1971 Experimental studies on interface friction characteristics of geogrids 1 2 1 YANG Guang-qing LI Guang-xin ZHANG Bao-jian 1. School of Civil Engineering , Shijiazhuang Railway Institute, Shijiazhuang 050043, China2.Hydraulic Electric Engineering department, Qinghua University, Beijing 100084, China Abstract The interface characteristics of geogrids would directly influence the safety and stability of reinforced soil retaining wall. So the interface index of geogrids in different materials was important when the reinforced soil retaining wall was designed. The main influential factors in the interface characteristics of geogrids, such as test method, load mode, effect of boundary and size of test, thickness and degree of compacting of the soil, and clip of the reinforcement, were analyzed in this paper. The direct shear and pullout tests were done for geogrids in clay and coarse gravel in laboratory. Some conclusions were found from the tests that the shear strength of the interface between geogrids and the coarse gravel was high, yet the shear strength of the interface between geogrids and the clay was low. The geogrids with large stiffness and the coarse gravel backfill materials should be selected to be used for high reinforced soil retaining wall. And the shear strength of the interface between geogrids and the clay should not be determined with the direct shear friction test. Key words geogrids interface; influence factors pullout test direct shear test [1-9] 8 . 949 p t P 4B L?σ tan? t 0 n p p 2Lσ tan? + 3 t B n p B [10] B L c ? B p p 0 ?σ n B 0 0.23.0 mm/min 0.1 20 mm/min Fig. 1 Normal stress distribution on reinforcement of soil 12 Pt Fig. 2 Interaction mechanism between reinforcement and soil P 2BL c +σ tan? 1 t p n p B L cp /? /σn p 30 cm P 2BLσ tan? +4B L?σ tan? 2 t n p 0 n p 950 2006 3 4