A caisson type foundation is generally used for power transmission towers in mountainous areas. The leg of the tower, which is a steel pipe with ribs, is embedded in the cylindrical concrete structure as an anchor. Some experiments have been…
A caisson type foundation is generally used for power transmission towers in mountainous areas. The leg of the tower, which is a steel pipe with ribs, is embedded in the cylindrical concrete structure as an anchor. Some experiments have been conducted .by pulling the . anchor for investigating the failure mode and ultimate capacity. It was found that the failure mode is the splitting one with cracks propagating from the pipe rib. This paper describes the simulation of the behavior of the concrete cylinder with pullout anchors. It is impossible to simulate the propagation of splitting cracks by a pure axial symmetric analysis. Therefore, a quasi 3-dimensional alalysis using an axial symmetric geometry with the smeared crack element and the non-linear constitutive model in the circumferential direction based on fracture mechanics was carried out. The results of the simulations showed the same failure mode and load-displacement relationship compared with experimental ones. Some real size foundations, having a diameter of three to five meters, were also computed by the same numerical method, and, it was found that the bearing capacity has a clear size effect which is proportional to diameter the minus one over four power.