Vacuum preloading method for non-water discharge sand cushion

Abstract

The invention relates to a large-area soft ground treatment method, in particular to a vacuum preloading method for a sand cushion without drainage. It includes the following main steps: 1) driving the drainage board in the shape of plum blossom piles on the treatment site; 2) arranging the horizontal drainage system to replace the medium-coarse sand cushion used in the previous vacuum preloading construction, and two types of laying can be used. One of the ways; 3) Connect the main pipe of the horizontal drainage system to the vacuum device, and carry out vacuum construction after film laying. The vacuum preloading method of the non-draining sand cushion of the invention is suitable for the reinforcement of large-area soft soil foundations, especially has a particularly good reinforcement effect on the blowing soil and the newly deposited ultra-soft soil, and saves a lot of investment in laying the sand cushion. , The vacuum degree transmission effect is good, and the horizontal direction drainage system of the laying method is steel wire spring tube + tube plate connector + drainage plate, which can realize large-scale finished product and standardized construction, short laying time, and can be recycled and reused. The unique advantages of short construction period and economical saving.

Description

Technical field: [0001] The invention relates to a large-area soft ground treatment method, in particular to a non-drainage sand cushion vacuum preloading method, which belongs to the innovative technology of the large-area soft ground treatment method. Background technique: [0002] With the acceleration of my country's modernization process, in the process of (coastal) city construction, a large number of soft soil foundations need to be treated. At present, the following three methods are widely used for soft foundation treatment: [0003] 1. Vacuum preloading method: This method uses atmospheric preloading as the preloading load. First, a layer of drainage cushion is laid on the ground, and then plastic drainage boards are inserted according to the designed spacing using a plugging machine, and then one to two covers are covered on it. A layer of airtight sealing film, and then use a vacuum pump to pump air to maintain a high degree of vacuum in the permeable material, g...

AI Technical Summary

Problems solved by technology

[0005] (1) Drainage sand cushions need to be laid. Generally, medium-coarse sand with a mud content of less than 5% must be strictly used. Generally, about 50 cm should be laid. For dredging or newly deposited ultra-soft soil and underwater vacuum preloading, It is even necessary to lay a cushion layer with a thickness of more than 100cm. The cost of laying a sand cushion layer will greatly increase the investment in the entire soft foundation treatment project.

[0006] (2) The vacuum degree provided by the vacuum pump must be transmitted to the soft soil layer through the permeable sand and gravel layer. Soil consolidation is slow and the treatment effect is not good

[0007] (3) After the construction of the vertical drainage system is completed, multiple main pipes and filter pipes must be laid as the transmission channels for vacuum degree, which consumes a lot of pipe materials

[0008] 2. Surcharge preloading method: Filling a certain thickness of filling layer on the site as a preloading load to achieve the purpose of reinforcing the underlying soft soil layer, but the amount of earthwork is huge and the processing time is long

This processing method has high construction cost and long construction period.

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