During the operation of the building, cracks appeared on the load-bearing walls, including window and door openings. The deflection of the slab inside the room was also visually noticeable.
Monolithic reinforced concrete floor slab with a thickness of 350 mm.
Strengthen the ground, fill the void at the point of contact of the floor slab and the ground inside the room.
Before starting work on strengthening the base, a comprehensive survey was conducted to determine the density of the soil base, identify low-bearing horizons of the soil thickness and detect voids under the floor slab.
To solve the problem of strengthening the ground, the method of deep injection was chosen. Work was carried out from the outside of the building, injection was performed in several levels, injection tubes were installed at a certain angle in accordance with the project.
To solve the problem of filling the void under the floor slab, work was carried out inside the building, injection was performed strictly vertically.
After the completion of work on strengthening the foundation soil and filling the voids, a complex of geodetic works was performed to install control marks for further observation and regular survey.