The Application Of Bored Construction Technology In Lhasa Liuwu Bridge Project

With the vigorous development of Chinese construction industry, the application field of bored pile becomes more and more widely. Bored pile as an important pile classification has the advantages of large carrying capacity, less impact on the surrounding environment, able to adapt to the merits of various complex geological conditions. Using bored pile construction can shorten the duration and reduce the project cost, and the construction of the necessary equipment is simple and easy to operate. However, bored pile also has its weakness, because of pile end soil is weak, so it will has weaken effect on the stability and bearing capacity of pile foundation, this is particularly true of bridges on sandy soil and loess area. Moreover, combined with the particularity of its structure, it will induce the bridge pile foundation to produce a series of diseases. The existing research and practice showed that post grouting technology can make up for the shortage, and can greatly increase the bearing capacity of pile end and pile side friction. Although there are a lot of theory researches on post grouting technology, the technology is not applied widely enough, and there is also lack of relevant technical specifications, so it did not reach the expected effect in the actual construction, a lot of engineering technicians did not take the technology, led to a lot of waste.In this paper, firstly, on the basis of related research at home and abroad, the basic principle, construction plan and construction method of bored pile technology have been summarized. Secondly, the construction quality control method at every stage of construction for bored piles, construction quality problems which easily occurrence and the corresponding treatment measures, and the detection methods for bored pile quality were analyzed, which can provide reference for the application of the technology. From the analysis, the author draws the conclusion that the use of post grouting technology, to a certain extent, can improve the bearing capacity of bridge pile, thus reducing pile diameter and shortening the pile length. Finally, based on liuwu bridge in Lhasa, combined with the engineering practice, this paper introduces the application of post grouting bored piles, the construction technology requirements and technological process are mainly introduced, which can provided the theoretical guidance and application reference for the application of post grouting technology.