Study On Optimization Of U-Type Anchor Pre-Stressed Pier

Pier of the large discharge structure is the critical structure to ensure that the arch gate could operate well under the high-thrust. As China’s hydropower developing, a growing number of large hydropower stations begin to construct, With the vent flow increasing, the working head is also rising, so is the structure force. Restricted by the size, pre-stressed structure must be used to satisfy the requirements of the force. Currently the main use of the pre-stressed pier anchor forms are silo contrary tensile type, cementation type and u-type. The former two types have been researched for many times, while the u-type is relatively fewer.Based on previous papers about u-type pre-stressed pier theory, this paper proposes non-linear contact simulation methods to analyze the role of u-type anchor mechanism. Compared with the previous micro-rod linear power transmission simulation method, contact transmission method reflects the role of u-type anchor more truly. Through the establishment of non-linear numerical model, master the law of concrete stress distribution in the u-type pier. In addition, establish simplified finite element model of different anchor radius, central angle, steel pipe radius and steel pipe thickness, so as to analyze the pier stress distribution influenced by these variables. Finally, summarize stress distribution law and provide the basis for the optimization of pier.Combined with practical projects, establish finite element pier models anchored by linear-pull type and u-type. Through the stress contrasts of the two anchor types, we can make a decision that because u-type don’t weaken the pier section, it makes the stress distribution around the anchor more uniformly. Some locations of the structure changed, such as at the combination of pier and anchor block face position, the stress curve is more smoothly. And it is fully verified the practicality and advantage of the form of u-type anchor pre-stressed pier.