Field pull out tests of FRP screw anchors

As a new-type of soil anchor,the fiber reinforced plastics(FRP) screw anchor has a lot of attractive properties,such as high strength,light weight,convenient installation,light pollution,high corrosion-resistance and low cost.The basic structure of FRP screw anchor and their field pull-out tests were introduced,and the test results of un-grouted and grouted anchors were presented.The maximum pull out force of the grouted anchors was about 15～20 kN with less pull out displacement compared with that of un-grouted ancthors,whose pull out force was about 10 kN.The pull out forces of both grouted and un-grouted anchors were compared with those obtained from design formulas.Finally,some ideas were put forward to improve the design and construction of FRP screw anchors.