SU759647A1 - Method of preparing bed in compressible and loose soils - Google Patents

Description

The invention relates to the field _ν soil hardening in the preparation of structures, in particular to. compaction of loose and weak ·

soil, mainly with the construction of columnar foundations.

There is a method of preparing bases by surface soil compaction by tamping punches with a flat p-1 punch.

The disadvantage of this method is the limited thickness of the compacted layer, which ensures the perception of relatively small loads, / what / 1? limits its use. ': /' /

Closest to the invention to the technical essence is the method of compacting embankments of a large thickness. and weak ground, including about-20 well formation by tamping blows, , e flat round stamp with compaction energy from 40 to 20Ό t »m £ 2]. .

/ The disadvantage of this method lies in the fact that despite the increase in the depth of compaction, there appear in the soil when it is loaded

horizontal displacements, as a result That is why it is possible to form unpermissible deformations under load, - * ^and

.- ·. / 2 '

those. the bearing capacity of the soil is not enough.

. The purpose of the invention is to increase the carrying capacity of the soil.

The essence of the invention is that the well is formed by beating tampers with a flat round stamp,

 Distinctive features of the proposed method are the implementation before the formation of a well, the laying of a reinforced concrete layer, a mixture in the form of a circle with radially arranged rods and the erection of an earth embankment with a thickness of .. equal to 1.0-1.2 punch diameters, and above the center of the concrete layer prior to its setting.

When this layer of concrete mix is placed with a diameter equal to 1.7-1.8 diameter of the stamp, and the radially located rods - in a circle with a diameter ,. equal to 2.2-2.5 punch diameter.

FIG. 1 shows the location of the armature / in the layer of concrete mix; in fig. 2 - section A-A of FIG. one; in fig. 3 - - a transverse section in the center of the layer of concrete mix after completion of work with an established column foundation. ·

The proposed method is implemented as follows ..............

For laying a layer of concrete mix with a diameter of Ϊ, 8 <3 mark the contour of the stamp rammer. With a diameter <3 nd install annular collapsible formwork 1 on a horizontally planned platform of the base 2 ..

Then install the second 'ring formwork 3 and put reinforcement,

radial rods 4 and distribution rings 5. The radial rods 4 are placed in the special grooves of the complete formwork 1 so that their ends are located in a circle dia-. 2.33 meter, In the formwork 1 lay a layer of 6 concrete mix, and in. the annular gap between the roadworks 1 and 3 cover the layer 7 of sand. A planning embankment 8 of soil with a height of 1.13 is erected on top of the concrete layered concrete layer. After that, the setting of the concrete layer 6 is carried out by the formation of the well 9 by repeatedly dropping the tamping platform 8 with a flat round punch with a diameter of 3 onto the surface, and the depth of the well should not be more than 1.0 3 ”. mechanical characteristics of subsiding and weak soils, which ..... ry lay down the base 2, the mass of the tamper is selected in the interval, 6-20 tons, and the height of the drop is taken from 3 to G2 m.

..... impact energy from 40 to 200 tons; m.

In the process of formation of the well 9, the soil core 11 is formed from the material of the embankment 8 in its sole 10; the ends of the radial rods 4 freely move from the Sand Ring to the monolithic concrete layer 6. After curing the shell 12 into the resulting well 9 establish

647 4

prefabricated columnar foundation 14, the diameter of which is made 1.3 times smaller than the diameter of the tamper 3.

The use of the proposed method of preparing bases for columnar bases erected on interbed and weak, for example, clay soils provides an increase in the bearing capacity of the soil by a factor of 1.8-2.2 times due to the limiter of horizontal displacements of soil particles immediately adjacent to the subshith of the foundation, reduction of deformations of the basement due to the spherical reinforced concrete shell joining to the earth core. '

Claims (1)

Claim 1. The method of preparation of the grounds 20 on subsiding and weak soils, mainly for columnar foundations, including the formation of a well with tampers with a flat round stamp, which is characterized by the fact that, in order to increase the bearing capacity, before the formation of the well, the reinforced concrete layer is laid in a circle with radially arranged rods and erection above it 30 unpaved mounds equal to 1.0-1.2 dimeters of the punch, and the formation of a well leads over the center of the layer of concrete mix prior to its setting. 35 2, the Method according to claim 1, about t and c ayi y and c with the fact that the layer of concrete mix is placed with a diameter equal to 1.7-1.8 of the diameter of the stamp, and the radially located rods - in a circle 40 with a diameter equal to 2.2-2.5 punch diameter.