METHOD OF PREVENTING TAPPING SLAB FOUNDATION BUILDING UNDER A COLUMN AT ADDITIONAL LOAD

摘要

FIELD: construction.;SUBSTANCE: invention relates to construction and is intended for prevention of damages of plate foundations under columns at their additional loading during reconstruction of existing buildings. Proposed method to prevent tapping of slab foundation under column under additional load by increasing stiffness of foundation under sole of slab foundation due to insertion of plate foundation of injectors into zone of extrusion and supply of hardening solution through them to state of reduction of soil. At first, by means of calculation boundary of zone of extrusion of plate foundation is determined in plan by its bottom at additional loading of column. Prior to additional loading of column in plate in area of foundation plate expansion, uniformly around string there are 3-4 through holes in the centre between axis of column and boundary of zone of plate extrusion, injectors are penetrated through the holes into the base soil to the depth of not less than the width of the extrusion zone from the additional load on the column. Value of the maximum allowable bend of the plate foundation under the column is determined. Hardening solution is injected through injectors under pressure exceeding pressure of soil rupture, creating stress-deformed condition (SDC) capable of absorbing additional load on column with preservation of integrity of plate foundation under column from construction of base lifting in design zone. During the additional loading of the column to the rated value, deformations of the curve of the foundation plate under the column during the injection of the hardening solution and additional loading of the column are monitored. Injection cycles of the hardening solution are periodically repeated in the soil of the base in the calculation zone until the stable state of the plate foundation is achieved under conditions of increasing the additional load on the column to the maximum value, and the number of injection cycles is determined based on monitoring results.;EFFECT: technical result consists in prevention of damage to foundations during reconstruction, reduced labor intensity and material consumption of operations, providing expansion of scope of use.;3 cl, 5 dwg