Experimental study on bond performance between polymer anchorage body and silt

The bond performance between polymer anchorage body and silt is studied through the ultimate pullout tests on vertical polymer anchors. Based on the field tests, the effects of pore size, density and length of anchorage body on the mean bond strength are investigated. Meanwhile the distribution of axial force of polymer anchor steel bars is also measured, and the distribution of bond stress between polymer anchorage body and silt under various loads is calculated subsequently. The test results show that the size, density and length of anchorage body have great impacts on the bond strength. The bond strength increases with the density and more obviously in low density. With the decreasing length of anchorage body, the bond strength increases, short anchor (2.5～ m) is optimum to exert the shear strength of soil mass, and long anchor (5 m) still has long effective bond length. The bond strength increases with the reduction of hole size. The concentrated bond stress area existing in the polymer anchor moves and widens to the bottom with the tensile load.