Strengthening the ground after washing out the soil under the floor slabs and re-leveling the structures

Problem:

During the operation of the warehouse complex, the base of the floor structures was accidentally moistened and part of the soil was washed out, which led to a change in the ground deformation modulus and damage in some areas.

Task:

Determine the degree of decompression of the base, outline the areas of soil leaching at the base of floor slabs and ensure the conditions for normal operation of the object, namely:

- eliminate the subsidence of the floor slabs within 50 mm,

- align the corners of the floor maps diagonally,

- eliminate the resulting rack system roll,

- ensure normal operation of doors in problem areas.

Solution:

First of all, GeoResin specialists performed a visual inspection of the object and assigned a list of further actions.

In order to determine the mechanical properties of the foundation soil, assess the uniformity of its composition, identify and size up the areas of decompression, dynamic penetration test was performed from the surface of the clean floor of premises at 22 points of the expected decompression site.

To determine the volume of voids formed under the floor slab structure at 34 points, a videoscope survey of the sub-floor space was performed.

Data on the irregularities of the slab were obtained by means of a geodetic survey and recorded in the report on the work performed.

After the results were processed in-house, a technical solution was developed that included:

- deep reinforcement of the 130m2 foundation soil of the floor slab structure by Deep Lifting method;

- filling 2.46m3 voids in the base of the floor slab construction by Floor lifting method;

- lifting and re-leveling of 130m2 of floor slabs in a horizontal plane, together with the elimination of the resulting roll of rack system by Floor lifting. The average value of the floor slab structure lift at the work site was +42mm.

All work was performed inside a functioning facility, with minor (not affecting business processes) restrictions on the functioning of its zones.