Post-tensioned prestressing cast pile and construction method thereof

Abstract

The invention discloses a post-tensioned prestressing cast pile comprising a construction reinforcing cage arranged in a concrete pile body. A plurality of common principle bars and a plurality of prestressing steel strands are arranged in the construction reinforcing cage, wherein each prestressing steel strand is a retarded adhesive prestressing steel strand or an adhesive-free prestressing steel strand; the top of the concrete pile body is provided with a pile top tension anchorage, and the bottom of the concrete pile body is provided with a pile bottom fixing end anchorage. The invention is a construction technology of firstly placing the reinforcing cage tied up with the prestressing steel strands and the common principle bars in a pile hole, and then casting concrete; the reinforcing cage does not deform, and the prestressing steel strands have high perpendicularity and stable position and are easy to tense. The prestressing tension is utilized to generate compressive pre-stress on the concrete, thereby increasing the durability of the concrete under harsh work conditions. As the tensile strength of the adopted prestressing steel strands is 5 times that of HRB400-grade steel bars, the steel usage can be saved by more than 50%, thus being beneficial for energy saving and emission reduction and generating obvious economic benefits and social benefits.

Description

technical field [0001] The invention relates to a cast-in-situ pile structure and a construction method thereof in underground engineering, in particular to a post-tensioned prestressed cast-in-place pile and a construction method thereof. Background technique [0002] In recent years, with the increasing development of the national economy, urban construction has also developed rapidly, and high-rise and super high-rise buildings have emerged continuously. At the same time, the development and utilization of underground structures with functions such as underground traffic, underground pedestrians, underground car storage, underground commercial use, and underground civil air defense are becoming more and more extensive. These conditions lead to deeper and deeper embedding of building foundations. Therefore, how to effectively solve the problem of anti-floating of underground structures has become a difficult problem often faced by engineering circles. There have been man...

AI Technical Summary

Problems solved by technology

Its shortcoming is: this kind of construction method is not suitable for long piles, and the length of piles used in soft soil areas often reaches more than 30m. Steel is a flexible material. Therefore, during the construction process, there are problems such as difficult positioning of the pile body, large changes in the size of the pile body, or displacement of the prestressed steel strand, and the requirements for construction machines are high, and the construction quality is difficult to guarantee.

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