Experimental studies were made on the strength properties of the main elements of high strength tie rod such as the threaded and ring parts of rod, the plates and pins of ring joint, the plate and universal pins of universal turnbuckle joint which had functions of turnbuckle and ring joint, and turnbuckle subjected to tension and bending moment or tension. Also the field investigation was made to study the actural loading conditions of the tie rods buried in the soil and typical cases of failure of high strength tie rods were introduced.
　Based on the results of laboratory and field investigation, the conventional method of design for the tie rod elements were discussed and recommendations were presented to improve it on several parts.