Identification of soil parameters based on the results of field tests of piles

Abstract

The work is devoted to the peculiarities of pile works in the soil under the action of static load. The data obtained from the results of in situ tests piles during the construction of a high-rise building were used for research. The calculations were performed by numerical modeling with using different models of soil environment and problem statements. 
 To increase the convergence of numerical modeling results with in situ tests, the parameters of engineering geological elements were identified.
 Several variants of the methods of modeling the calculation scheme of systems "pile-soil massif" are analyzed. Different approaches to modeling the structures of the pile foundation and soil massif, finding the size of the soil massif and its finite elements, input parameters of soils are considered. The influence of the construction of a finite-element model on the results of calculations is obtained. For the analysis of the data, graphs of pile displacements under load were constructed. The dependence of the mechanical characteristics of the soil on the nature of the curve «load-subsidence» is determined.
 Based on the comparison of the results of the in situ test and computer modeling of the pile test with static load, an iterative process of identifying the deformation characteristics of soils was carried out.
 The influence of the use of the identified parameters of the soil environment on the formation of the stress-strain state of the «base – foundation – superstructure» system in the calculation of a high-rise building has been studied.
 The calculation scheme is created in accordance with the real geometry and features of the soil conditions of the construction site.
 The results of identification are included in the FEM for the analysis of the stress-strain state of the structures of building and base.
 The results are compared with the calculations of high-rise buildings, which were conducted in previous studies by scientists in the field of geotechnics.