SU958590A1 - Method of thermal consolidation of soil - Google Patents

Description

The invention relates to the construction of foundations and foundations of buildings and structures by thermally hardening the ground.

A known method of thermally strengthening the soil., Which includes drilling a well, sealing it with a shutter, burning combustible mixtures in the well, injecting hot gases into the soil 1,

Closest to the present invention is a method of thermally strengthening the soil, including drilling a well, sealing it, feeding combustible mixtures into the well, igniting the mixtures to form a torch and injecting hot gases into the soil 2,

The disadvantage of these methods is the relatively long duration of burning of the soil, amounting to 1.1-1.2 m / day, which is due to the successive injection of hot gases into the soil along the height of the well.

The purpose of the invention is to reduce the duration of the process.

The goal is achieved by the fact that in a method that includes drilling a well, sealing it, feeding combustible mixtures into the well, igniting the mixtures to form a plume and injecting hot gases into the soil

the wells are staggered downwards, while the supply of combustible mixtures to the second and subsequent lower stages of the well produces cooling of the mixtures with the agent within the upper stages, and the formation of the plume is carried out at each step of the well.

At the same time the supply of combustible mixtures

10 at each stage, except for the lower one, is produced uniformly around the perimeter of the safety line, the ignition of combustible mixtures is carried out sequentially from the bottom up, and as a cooling agent is used

15 water.

Fig. 1 shows a well and a reinforced soil array, a longitudinal section; Fig. 2 shows the layout, or the pipelines for supplying hot mixes and a cooling agent,

The technology of the method is as follows.

First, the borehole 1 is drilled to the height of the lower stage 2 with a diameter of .15025 180 mm, the upper stage 3 is drilled with a diameter of, for example, 180-240 mm. Then cut off the separator 4, which separates each other: steps 2 and 3 from each other, with an opening 5 for introducing an electric or other igniter 6. After that, the lower part of the gap 7 is installed, pipelines 8.9 and perforated pipe 10 are installed into the well 1 of combustible and additional air or water, and the ring spray pipe 11 burn their mixtures into the upper stage 3 and mount the lid of the bolt 12 on which the baffle 13 is located. Then drill the hole 14 along the outer contour 15 of the strengthened soil mass 16 and set Multispaced thermocouples 17 are wound therein, connecting them with a recorder 18. Flammable mixtures are ignited to form a flare 19 in the lower stage 2 using a pilot 6, which is lowered into the hole 5c of the shut-off valve 4 and the output of stage 2 to the operating mode. At the same time through the pipeline 9 serves air or water. Then zpalnik 6 move up to the level of the annular spray 11 and form the torch 20 on the top of the upper stage 3, its output also on the operating mode. Gag is extracted from well 1 through pipe 13, which serves to visually monitor the combustion processes of combustible mixtures in well 1. Air or water is fed through a perforated pipe 10 into the upper inlet. Combustion of combustible mixtures and injection of hot gases into the reinforced soil mass 16 is carried out until the design temperature reaches its external contour 15, which is recorded by the readings of thermocouples 17 and recording instruments 18. Reduction of the duration of thermal soil stabilization in the proposed method is throttled due to simultaneous heat exchange over the entire height of the well 1. At the same time, such a possibility is ensured by the fact that the supply lines for combustible mixtures 8 in the sections of the well 1 that pass through the upper stages 3 are cooled by air or water. This circumstance excludes the ignition of combustible mixtures in the upper stoppers. It is more expedient to use water as a cooler, which serves not only to cool the pipeline 8 for supplying combustible mixtures, but also as an additive, which intensifies the heat exchange between the hot gases and the earth wall of the well 1. In FIG. 1 shows well 1 with two steps 2 and 3 in height, which, with a flare length of .8–12 m, corresponds to the depth of the massif to be 16-24 m. pillars with a diameter of 2 m. The wells were drilled with a PVVS-15 machine to a depth of 20 m, in two steps of 10 m each. The diameter of the first stage was 0.15 m, the second was 0.2 m. Combustible mixtures of natural gas were used, the calorific value was 35 mJ / m, and compressed air was supplied from a DC-9M compressor under a pressure of 0.2 MPa. The ignition temperature of combustible mixtures amounts to 550 ° C, and the burning rate of the soil is O, 4 M7H. A comparative analysis of the thermal strengthening of the foundation meter according to the proposed and known methods is given in the table.

Diameter of the strengthened massif

soil contour 300 ° C, m

Duration-work, h

Total:

including burn well

Duration of work

on the first step

at the second stage

Labor costs per meter

fortified soil, h / d

. Cost of 1 m fortified soil, p

160,154

154

0.82 6.91

Claims (4)

Claim 1. The method of thermal strengthening 10 of the soil, including drilling a well, sealing it, supplying combustible mixtures to the well, igniting the mixtures with the formation of a torch, and injecting hot gases into the soil, characterized in that, in order to reduce the process time, · Well drilling is carried out stepwise with decreasing downward, during combustible mixtures in the second and subsequent lower stages of the well, mixtures are cooled by the agent within the upper stages, and the formation of a torch is carried out at each well stage. 2. The method according to π. 1, characterized in that the supply of combustible mixtures to each stage, except for the lower one, is carried out uniformly around the perimeter of the well. 3. The method according to PP. 1 and 2, characterized in that the ignition of the combustible mixtures is carried out sequentially from the bottom up. 4. The way to pop. 1, they are distinguished by the fact that they use water as a cooling agent.