Compound vacuum precompressed soft foundation comprehensive strengthening method

Abstract

The invention discloses a composite vacuum pre-stressed soft foundation comprehensive reinforcement method, which is characterized in that the construction method comprises a vacuum pre-stressed precipitation and an electroosmotic precipitation. The execution steps are as follows: a) Establish a yard drainage system; b) Perform vacuum pre-stressed precipitation; c) Perform electroosmotic precipitation at the same time of step b), or when water output is lowered in step b; d) When degree of consolidation reaches a level higher than or equal to 85 percent, steps b) and c) are over to enter a low-energy forced ramming; e) Perform vibration steamroll to flatten the yard. Through composition of utilization of the two construction methods of the vacuum pre-stressed and electroosmotic precipitations, the invention retains advantages in prior vacuum pre-stressed construction methods. Meanwhile, in combination with the electroosmotic precipitation, the invention fulfills application of the vacuum pre-stressed construction method in sludge-like (low permeation factor) soft earth foundations, so that the reinforcement depth of the soft earth layer can be increased, but construction period can be shortened.

Description

technical field [0001] The invention relates to a foundation reinforcement method, in particular to a foundation reinforcement method for large-area deep soft soil, which is suitable for flowing mud, silt, and silty soil foundations, especially for soft soils with high bearing capacity but general deformation requirements. Soil foundation reinforcement. Background technique [0002] Vacuum preloading is a large-area soft foundation reinforcement technology. Because of its low engineering cost and good reinforcement effect, this construction method began to be applied in my country after the 1980s. The basic method is: set plastic in the soft soil foundation that needs to be reinforced. As a vertical drainage channel, the drainage board is combined with a horizontal drainage channel composed of a sand cushion layer laid on the ground and a mesh drainage filter pipe, and covered with an airtight sealing film, through the water absorption channel buried in the sand cushion layer...

AI Technical Summary

Problems solved by technology

For the vacuum preloaded foundation with plastic drainage boards inserted, after the drainage and exhaust channels are set, it is only suitable for the permeability coefficient ≥ 10 -5 cm / s site works, but has no effect on the consolidation of silt with a smaller permeability coefficient;

[0005] 2. Vacuum preloading needs to lay a 500mm sand cushion on the ground as a horizontal drainage layer, but in actual construction, it cannot be realized because mechanical equipment cannot enter the site on mud and other foundations;

[0006] 3. The bearing capacity of vacuum preloading is not high, it can only reach 80kPa, which cannot meet the requirements of buildings for bearing capacity;

[0007] 4. Due to the constraints of equipment and other factors, the time required for traditional vacuum preloading is very long, 3 months or longer

[0008] The existence of the above shortcomings has limited the expansion and application of the vacuum preloading method in engineering.

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