Security of Short Piles for High-Rise Building in Nanning

In Nanning basin, because of the peculiar relief and stratum model, the bearing support soil layers for pile foundation of high-rise buildings generally is gravel layer or mudstone layers or sandstone layers. On first or second terrace in basin, gravel layer is most chose as the bearing stratum for pile foundation of high-rise buildings. Static driven piles are commonly used in Nanning, because they have advantages of fast construction, high bearing capacity and noiseless despite costly. It is inevitable to form short-piles foundation, as a result of the length of piles will be too short for need of basement and becoming diminishingly thin of overlaying soil which terraces gradually rise to results in. Therefore many academic and engineering problems are occurred, which make engineers confused. Base on studying many engineering cases, conception and application and research situation for short piles were discussed in this paper, and some problem that aimed at to be brought about in Nanning stratum model, for example, calculation mode, vertical bearing capacity of pile foundation, construction cost, stability, construction and so on, were analyzed. Approach of settlement above problems was proposed. At the same time, it is considered to be a future potential danger if short piles are not droved into the bearing support layer of piling foundation.