Model Test Study of Soil Nailing Wall in Silty Clay in Beijing

Based on similarity theory, the similitude ratio of model test was confirmed. The similar material was selected and the physicalmodel of soil nailing wall for the experiment was built according to similitude ratio . The reasonable testing system, loading system, rainfall system and testing procedure were designed. The date of the horizontal displacement of soil nailing wall top, axial force of soil nails, earth pressure and so on are tested and analyzed. The result shows that the primary factor which affects the displacement of soil nailing wall is the soil stress redistribution caused by pit excavation, and every excavation would make horizontal displacement of the wall top stepped increasing, horizontal displacement reaches 2.3‰ of excavation depth in the excavation and supporting stage; the horizontal displacement of the wall top increases with the growth of excavation depth, lateral earth pressure of soil nailing wall first increases and then decreases with the pit excavation; rain can soften silty clay and increase deformation of the wall.