FEA Of Pre-stressed Anchor Device Under Stress And Dimension And Material Optimum Of Anchor Head

Anchorage device is the key part for the effective transfer of pre-stress. With pre-stressed technique widely used in bridge construction, architecture and hydraulic engineering, etc., great attention is paid to the most economic dimension and material cost, under the safety of anchorage device.At present, conventional design keep the principle that bigger dimension is safe. And until now, no theoretical formula can be used to calculate the stress and strain of the anchor ring because of its complexity.Based on the structure and working condition of the anchorage device, geometries of the anchor head, intermediate plate and pre-stress wire were simplified here and linear hardening elastic-plastic model was used. After friction coefficient was set, the 7-hole anchorage device under stress was analyzed by using FE software.Taking account of steel dimensions and machining requirement, the diameter of the anchor head was set to 135mm and 126mm, respectively. Comparing the simulation results of the same diameter anchor head, the optimum height of the anchor head was obtained. Then the optimum of material was followed. By comparing the simulation results of two kinds of materials under their different states, modified treatment of 45 steel can substitute 40Cr to reduce the material cost. At last, an experimental verification was carried out. The experimental results and the simulation results are coincident well, which proves the numerical model of the anchor head developed in this paper is applicable for the practical analysis of the anchor head.Through this research, the results obtained can be used for the design of the anchor head and the selection of material.