Design Method of Long-Short-Pile Composite Foundation Base on Tangent Modulus In Situ Loading Test Curve
The settlement of each part of the composite foundation, such as the foundation mat, cushion, soils and pile head, is recognized as equivalent under normal working conditions. On the basis of this, the corresponding load on long-short pile and soils can be derived easily from each individual p-s curve. The p-s curve of the composite foundation can be pictured in terms of the mutual actions of all the components mentioned above. and thus the corresponding settlement with load will be determined. Meanwhile, the p-s curve can be obtained via the undisturbed soil hyperbola tangent modulus method, which not only characters the nonlinear relationship between load and settlement very well, but also shows the deformation compatibility among those components. It is found that designed bearing capacity of soil is much higher than the reality based on usual design norms of composite foundation, while pile load is greater than the designed ones, which can be credited to the deformation compatibility of pile-soil not considered.
Chaohe Chen, Yong Huang and Guangfan Li
P. Liu et al., "Design Method of Long-Short-Pile Composite Foundation Base on Tangent Modulus In Situ Loading Test Curve", Advanced Materials Research, Vols. 243-249, pp. 2314-2323, 2011