Long-term Settlements Assessment of High-rise Building Groundbase Based on Analytical Ground Deformation Diagram

Abstract

In real conditions of the building and operation the loads on the ground bases are applied by stages at the moment of construction buildings or structures. Active load stages during the construction are replace to stages of long exposure under load. In this connection there is necessity to improve the settlement calculation methodology of foundations under the regime long static loadings. Were performed high-rise buildings foundation settlements numerical studies with using different computational models, including the modified model of Pasternak at the basis of analytical ground deformation diagrams under triaxial regime loading. The test building has a frame-wall system, which is made from reinforced concrete and has the following parameters: total height of 144.9 m (39 floors); number of underground floors – 4; depth of laying the foundation – 15.15 m; raft foundation square – 1377 m2. For description of ground stress-strain state changes under regime loading, were developed analytical diagram of ground deformation at the coordinates “deviator stress – linear deformation” in the conditions of triaxial compression. Were constructed initial ground deformation diagrams for short triaxial static loading and transformed diagrams for prolonged triaxial regime loading, taking into account the changes in the mechanical characteristics during these loadings. Performed numerical studies of high-rise building foundation groundbase settlement on the basis of the proposed model allowed to calculate results, which have a good agreement with monitoring data. Deviation estimated average settlement from the real was not more than 1%.