Experiences with Tip Post Grouted Drilled Shafts in China
It is known that the tip post-grouting technology can enhance the bearing capacity of drilled shaft and can reach the purpose of optimizing shaft length, and reducing cost. In this work, the key points of design and construction technology for tip post grouting in Chinese practices are introduced primarily. Furthermore, the mechanism of improvement for tip post-grouting drilled shafts is analyzed on the basis of the strengthening mechanism of tip post grouting, which indicates that the tip resistance of the grouted shaft is mobilized before performing vertical load due to the preloading effect of soil beneath shaft tip arising from tip grouting. Consequently, the asynchrony of the side resistance and tip resistance of pile are improved. Finally, two cases are selected to further study the influence of post grouting on the bearing characteristics of drilled shafts.
This work was support by the Major State Basic Research Development Program of China (973 program) (No. 2013CB036304), and the science and technology project on transportation construction in Yinchuan, China (K2014K063-01-05).
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