SU1222761A1 - Method of compressing the underlying soil - Google Patents

Description

The invention relates to the construction, and in particular to methods of strengthening the foundations of buildings and structures by compressing the soil.

The purpose of the invention is to increase the efficiency of the base dredging.

FIG. Figure 1 shows a vertical section of the foundation, the base of which is compressed by the proposed method; in fig. 2 shows section A-A in FIG. one. .

When the soil is compressed around the upper part of the foundation 1, the foundation pit 2 is torn off and a layer 4 of granular material from small fractions of the bottom flap form is filled with concrete is laid on the surface of the sinuses 3, and the top layer 5 of granular material 5 is added to this layer. Ow Yush. Concrete filler.

After that, a reinforced concrete slab 6 with ribs 7 is borne on the surface of the layer. When filling the upper layer 5 of its outer surface, the inner surface of the plate 6 is shaped and grooves are provided for the fins 7. The ribs 7 and the slab 6 are reinforced with nets or frames.

It is recommended that the bulk material of the small fraction of the leshe, hellish form has a grain size of 20-30 mm.

This fraction is obtained as waste when screening w, ebn and gravel. The grain size of the bulk material of the bulk fraction should not exceed half the thickness of the bulk material.

The armature of the plate 6 and the ribs 7 are attached to the foundation 1 by welding it with the bare reinforcement of the foundation. In order to increase the resistance of the slab with the material pushed through it, the additional fastening can be installed in the form of bolted metal beams 8 welded to the reinforcement of the column 9 and monolithed with it after the work is finished.

Before bernirovanie plate 6 in the body of its put metal tube 10 with a thread at the upper end for the installation of valves and connection to the hoses of mortar pumps (not shown).

After the concrete slab 6 is set to design strength, cement-sand mortar is injected through pipes 10 into it. For

To prevent the solution from breaking through, the area of the pit 2 is covered with soil. The cement-sand mortar, filling the voids between the coarse fractions, reaches a layer of the material of a fine fraction of a flaky shape. Tight contact of the surfaces of the grains of this fraction increases the resistance to penetration of the solution through this layer, which makes it possible to increase the pressure of the cement-sand mortar under the slab, prevent intensive cementation of the soil beneath it, and ensure different compression of the soil under the slab having different compressibility characteristics. In this case, the plane of contact of the soil with a layer of material of the fine fraction of the flaky shape is deformed.

The rise in pressure of the solution is stopped with the achievement of a predetermined value; in this case, each surface area of the non-uniform compacted soil under the slab provides the same reactive resistance, i.e., it provides a uniform reaction over the entire area of the new foundation.

After the mortar has hardened, layer 4 becomes a preparation for a new foundation connected to the foundation by slab 6 as a whole.

The pressure setpoint can be a pressure, the resultant of which does not exceed the weight of the superstructure.

If necessary, a group of foundations, such as under conditions of developing uneven deformations due to rising groundwater levels, first perform all operations prior to the injection of sand-cement slurry under the slab, and then simultaneously under the slabs of all foundations, the solution is injected.

The method allows to differentially compact the heterogeneous bulk soil of the basement sinuses, creating a compacted foundation for a new expandable foundation, perform simultaneous reinforcement of the foundation group, use mining waste and crushing of rubble in quarries in the form of flaky fractions, strengthen the foundation with the minimum possible depth of the new incremental foundation, to monitor the degree of soil reduction, to obtain a foundation with increased resistance to horizontal loads.

1Fig .2

Claims (1)

METHOD FOR COMPRESSING THE GROUND SOIL, including placing on the ground surface granular material, forming a concrete slab on it with a through vertical hole and ribs around the perimeter, covering the granular material, and pressing the granular material into the soil, characterized in that, in order to increase the efficiency of soil compression , bulk material is placed in horizontal layers, the lower of which is made of aggregate of fine fraction of merciless form, the upper is of aggregate of concrete of large fraction of merciless form, and was imparted to the particulate material in the ground is carried out by pumping a cement-sand mortar into the cavity plate through the vertical hole. FIG. 1 SU „, .1222761