Experimental study on time effect of pull-out characteristic for anchor in slope

Different loading tests for studying pull-out characteristic for anchor were did for getting anchoring force in phyllite area of south Shan'xi province,long-term changes for stress and corresponding relationship between stress and displacement were summarized.As the results exposed that stress increasing in the potential sliding surface of the anchor lags behind with which in the head of the anchor when took the level-load mode.While took the instantaneous load to the ultimate tensile strength mode,stress from sliding surface in hole was not sensitive to the external load.Stress from the head of the anchor and the potential sliding surface took about one year to simultaneously reach steady state under the level-load mode.And stress in the hole took a long time to adjust reaching the steady state,longer than the time took by stress from the potential sliding surface under the instantaneous load mode.