Method of Alignment of Tilts of Objects with Large-Size Foundationsand Increased Loads on Them
The basic scheme for calculating the bases of large-sized foundations is, at present, a scheme of a linearly deformed layer of finite thickness.Calculationsof the settlements, carried out according to the formula based on this scheme, still fully satisfied the practice of construction. A large operational experienceand the results of long-term observations for the settlements of the foundations show that the actual settlements of the foundations much larger than thecalculated values determined by the settlement calculation formula based on the theory of this model. The material of the actual settlements of the constructedobjects on large-sized foundations under increased loads shows that the settlement curves consist of linear and non-linear sections. The linear section hasa place for medium-compressible soils for the first half of the calculated average pressure P II mt, i. e. at P II mt ≤ 250-300 kPa. W hen P II mt is more than thesevalues, the settlement speed begins to increase in the process of increasing the load to its full calculation value. Then the settlement speed decreases andthe stabilization phase begins. The linear section of the settlement graph characterizes the process of soil compaction. The increase in settlement speedsin a nonlinear section should be explained by the increase in the role of horizontal displacements in the general deformation of the base. The fact that horizontal displacements play a significant role in the overall settlement of the structure is confirmed by numerous studies of the bases under reservoirs andembankments, and in small-scale experiments. The account of horizontal displacement makes it possible to bring the actual settlements maximally to thecalculated ones.