Construction method for steel guide wall foundation of sea area deep-water anchor foundation

Abstract

The invention discloses a construction method for a steel guide wall foundation of a sew area deep-water anchor foundation, and the construction method is applied to suspension bridge anchor foundation construction of sea area deep-water. The construction method comprises a foundation treatment step, an auxiliary steel platform set-up step, a steel guide wall construction step, an even wall slot section division step, an II-stage slot sand backfilling step, an I-stage slot construction step, and an II-stage slot construction step. According to the construction method disclosed by the invention, foundation treatment is performed at an early stage to improve geological conditions, the auxiliary steel platform is set up to create land-area working conditions, steel tube piles are positioned,inserted and punched to inner and outer sides of the axis of an even wall, and construction on the even wall is performed, so that the effects of supporting, retaining water and retaining waves are realized for later-stage foundation pit excavation. The construction method solves the technical problems such as construction hole collapse, a relatively long construction period and disassembly afterconstruction as sea suspension bridge deep-water anchor construction in the prior art needs cofferdams for building an island, reduces construction risk, shortens the construction period, and providesa novel technical method for constructing and applying a cross-sea channel kilometric suspension bridge.

Description

technical field [0001] The invention relates to the field of civil engineering, in particular to a steel guide wall foundation construction method for deep-water anchorage foundations in sea areas, and more specifically, to a steel guide-wall type ground connection wall foundation suitable for anchorage foundation construction of deep-water suspension bridges construction method. Background technique [0002] At present, the anchorage of the kilometer-level cross-river suspension bridge adopts the structural form of the gravity anchorage, and the gravity anchorage includes two parts: the main body of the anchorage and the foundation of the anchorage. The construction of the existing gravity anchor requires the excavation of the foundation pit. In the early stage, it is necessary to adopt the technology of ground wall foundation to realize the support function of the foundation pit excavation, and the site needs to be selected and built on the bank with good geological condit...

AI Technical Summary

Problems solved by technology

The construction of cofferdam islands in deep water areas requires filling 10m of medium-coarse sand on the soft silt layer with a thickness of 15-20m on the top of the original riverbed, which seriously breaks the balance of the original riverbed soil. Although the island is surrounded by strong steel pipe pile cofferdams However, the fluid silt and silt soil on the inner and outer sides of the cofferdam are in an unstable state in a short period of time, which may easily lead to hole collapse during the milling construction of the ground connection wall, resulting in serious construction quality accidents

[0005] 2. Construction period risk

The construction of cofferdams and islands requires a large amount of work and a long construction period, and because the stability of the river bed soil is broken, it also has a great impact on the marine environment, and after the formation of the islands, it needs to wait for 3 months or even longer to wait for settlement. The milling construction of the ground connection wall can only be carried out after stabilization

[0006] 3. Post-work processing risks

After the completion of the bridge construction task, in order to meet the water blocking requirements of the marine ecological environment, the temporary cofferdam islands of the anchorage in the sea need to be removed. At this time, it is almost impossible to use a vibratory hammer to pull out the large-diameter steel pipe with a depth of 40m in the soil. The seabed is faced with large-diameter steel pipe piles for underwater cutting to meet the water blocking area requirements. The risk of underwater cutting is extremely high and wastes resources. The temporary cofferdam is extremely expensive to dismantle in the later stage of island construction.

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