SU910929A1 - Method of thermal consolidation of soil - Google Patents

Description

The invention relates to the reinforcement of soil in the construction of buildings and structures, in particular to the strengthening of the soil by thermal effects on it.

A known method of thermally strengthening the soil, including the formation of a well, its sealing by a gate, burning in the well of combustible mixtures and the injection of hot gases into the soil

The closest in technical essence to the invention is a method of thermally strengthening the soil, including drilling a well, sealing it, burning combustible mixtures and supplying hot ha into the soil, G2.

The disadvantage of these methods lies in the incomplete use of the carrying capacity of the soil due to the formation of a weakened layer around the burned soil mass, treated with the effect of a temperature equal to SO-3OO C.

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

The goal is achieved in that according to the method, which includes drilling a well, sealing it, burning combustible mixtures in a well, and supplying hot gases to the ground, after feeding hot gases into the soil, they drill the well to the soil layer with a temperature equal to 100 ° C. ZOO C, and then lead to the hardening material in this layer of soil.

In this case, the flow into the soil of hot

10 gases are carried out at a temperature determined from the ratio

(tt-1

rt + -

w

 1G1-gz

15

where r is the temperature distribution radius t.100 С, m; g is the radius of temperature distribution t 30pC; Gr - spreading radius 20

even temperature tp, M; m - thermogram indicator,

determined from the ratio t (1 + 4G) (0.5-1.21 LR-0.001T), where G is the degree of soil moisture;

25 DR - overpressure hot

Claims (2)

gases in the well, MPa; С - duration of injection of hot gases into the ground, h. Figure 1 shows the well and 30 fortified array of soil, a longitudinal section; figure 2 is a variant of the intake of hardening material. The method is carried out as follows. Drill well 1, seal it with gate 2 with nozzle 3 to feed combustible mixtures into well 1, burn combustible mixtures and pump rushing gases through wall 4 of well 1 into the fortified soil mass 5 until the temperature is equal to 500,600 ° C, will not reach its external boundary b. After that, the barrier 2 is removed and the subsequent drilling of well 1 to the weakened layer of soil 7 with a temperature of 100300 ° C is carried out. Then the pipeline 8 with the receiver 9 is immersed in the borehole 1 and hardening material, for example cement-sand mortar, is fed through it into the weakened soil layer 7, under excessive 1 pressure, adjusting it with the valve 10 until the hardening material reaches the required level 11. If required reduce the forces of grip and adhesion of the reinforced soil mass 5 with rock 12 along the lateral surface of its external contour b, then solid material is pumped only to the height of the bearing part 13 of the reinforced soil mass 5, and the rest 14 is filled with es conduit 15 with valve 16, cold water or relaxing material, e.g. GOVERNMENTAL petroleum bitumen. The method makes it possible to implement the regularities found experimentally and theoretically, and it has been established that in layers of soil heated at 100-300 ° C, the forces of internal friction and adhesion are reduced against the initial ones by 7.1-22.5% and reduced bearing capacity of the soil. Example. At the site of work, thermal strengthening of the pile with columns (supports) of 0–1 m is carried out. Depths on the landing thickness of soil are 6 m, its moisture content is 0.48, and the design firing temperature is tp 600 ° C. The wells of 1.0 0.18 m are drilled with a PPVS-15 drilling machine and are buried in the reference horizon 17 by 1 m. A hot mixture of saline oil with a calorific value of 40,000 kJ / kg and compressed air from the ZIF-55 compressor is burned with excess In the well 1, equal to 0.06 mPa V, well 1 is maintained at a temperature of 980 ° C. After 92. hours of injection in the CNT of hot gases, thermocouples installed on the external circuit 6 of the reinforced soil mass 5 show the temperature. At this temperature, roasting of the soil continues for another 2 hours. Then, wells 1 are depressurized and "drilled 0.7 m to a weakened layer of soil 7 with a temperature of 200 ° C, which is 0.3 m thick, and a cement-sand solution of composition 1 is injected into this layer. : 2 for the height of the supporting part 13. After 7 days, the supports were tested by test static loads with ground dies with hydraulic jacks DG-200. At the same time, in order to compare the results, thermal strengthening of the soil in the supports is carried out in a known manner. The results of the comparative analysis are given in table. 1. Table Firing duration, h. Bearing capacity 182 supports, ts126. Performance 1.34 1.96 firing, tsPr and M er. 2. At the site of work under the conditions of example 1, after introducing sand-sand into the weakened layer of soil 7 a solution of composition 1: 2, around the supports, made by known and proposed methods, the soil is subjected to soaking for 10 days, bringing the degree of moisture to 0.60-0.84. After this, the load bearing capacity is tested with problematic static loads. The test results are shown in Table. 2. Tablitsa 2 Method Indicators predisposed 1 loadable Bearing capacity of the support, ts32 83 Firing productivity, tf / h0.34 0.83 Application of the proposed method allows to increase the performance of thermal strengthening of the soil in 1.44-2.6 At the same time reduce the cost of roasting the soil by 15-23%. Claim 1. Thermal hardening method, including drilling a well. its sealing, burning in the well of combustible mixtures and the delivery of hot gases into the ground, characterized in that, in order to increase the carrying capacity, after the hot gases are fed into the soil, the well is subsequently drilled to a layer of soil with a temperature of 100-300 seconds and then hardening material is injected into this soil layer. 2. A method according to claim 1, characterized in that the supply of hot gases to the ground is carried out at a temperature determined from the ratio of hertz to the radius of temperature C, m; G- is the radius of temperature t ,, M; g is the propagation radius of racPr even temperature Zr, m; m is the thermogrg mgsh index, determined from the ratio m (1 + 4G) (0.5-1.21AP – 0.001 СГ), G is the degree of soil moisture; DR - excess pressure of hot gases in the well, MPa; 1J — duration of injection of hot gases into the ground, h. Sources of information that are considered in the examination. USSR author's certificate 3005, cl. E 02 D 3/10, 1976. The author's certificate of the USSR a ve 2829585 / 29-33, E 02 D 3/14, 1979.