Research On The Use Of Later Low-pressure Grouting To The Drilling Hole Pour Pile

The drilling hole pour pile technique has been wide-ranging used in the high buildings' foundation and base of the wide span construction and base of bearing weighty load construction,but the geology conditions that surrounding the pile are differ in thousands of ways,extraordinary,the soil there is small opening and it can be compressed and the bottom of the pile's hole there is much more dregs,so many confuse reasons can't be computed weaken the pile's ability of bear load. So that,the reality ability of bear load is very different from the design count. In order to reduce the affect which weak the pile's ability of bear load of soil's small opening,from 20 years' of the last century,many developed countries such as English and American,began to study the later pressure grouting at bottom of the pile's technology and have succeeded. Today,there have been many mature working technology and have been making out perfect design way and working on standard.It's 70 years' last century that began to test study in our country,today we have mastered some working ways. More and more pile foundations of high buildings use later pressure grouting technology to improve the pile's bear ability from 80 years' last century. The working technology and the design way were continuously improved and perfect. But there isn't unified and explicit design way and standard to be used by designer,there are different views on the design theory too. Someone think it must use permeating theory to design,the others think it must use permeating theory to design. The Building Ministry made out the working standard of the later pressure grouting of pour pile,but it stand at the industry standard,isn't enough perfect and comprehensive. In this paper,the author put forward the design principle by analyzing the reasons that affect the bear load ability of the drilling hole pour pile and the principle that improve the bear load ability of single pile by later pressure grouting,put forward the working technology and requirement of check before acceptance byanalyzing and summarizing several models such as The Chinese Railway 11 Office residential high building. The paper will supply some additional function to today's standard.