Construction method of backfill in layers for sea reclamation

Abstract

The invention provides a construction method of backfill in layers for sea reclamation, which includes the steps: selecting shipborne machines; setting a middle cofferdam; distributing pipelines and backfill pipe openings; setting drain openings; backfilling; and draining water. The construction method has the advantages that in the process of backfill in layers, muddy clay is dug and backfilled to a lower layer of a reclamation area, and high water permeability soil such as powered clay, silt, mealy sand and the like in the lower layer are dug and evenly backfilled to the upper layer of the reclamation layer to form a soil layer 1.0-1.5m in thickness; after backfilling is complete, surface ponding is organically drained, surface soil 1.0-1.5m in thickness is high in bearing capacity and forms highly durable service bedding, and good foundation is laid for subsequent construction of a soft foundation. The process of backfill in layers has evident advantages in terms of construction period, quality, cost, safety and the like, and deep dug portions are beneficial to construction of deepwater channels according to the requirement of layered soil obtaining, or the deep dug portions serve as preserved depth for sedimentation for the channels, so that subsequent maintenance cost of the channels is reduced. Therefore, the problem that human, machine and material internal operation in construction of ultra-soft foundations cannot be realized is solved.

Description

technical field [0001] The invention relates to a method for land reclamation from the sea, in particular to a layered mud blowing construction method for land reclamation from the sea. The invention proposes a layered blow-fill process, which blow-fills the deep fine sand to the surface to form a working layer with higher bearing capacity, which provides good conditions for the subsequent soft foundation treatment, greatly reduces the project cost, and shortens the construction period. Similar land reclamation projects provide useful reference. Background technique [0002] Due to the extremely high water content of the soil and the extremely low surface bearing capacity of the land formed by the conventional mud blowing process for land reclamation, it is difficult to immediately carry out deep reinforcement treatment, and it is impossible to provide usable land for project construction as soon as possible, which is not conducive to early exertion of investment benefits. ...

AI Technical Summary

Problems solved by technology

[0004] The first method is to lay woven geotextiles on the surface of the dredged fill soil + lay thorn fences or bamboo fences, plus lay geotextiles and dredge sandy soil with a thickness of 80-100 cm to form a working cushion with a certain bearing capacity. The additional cost of rice is 70-80 yuan, and the construction quality is difficult to guarantee, and the construction period is difficult to determine due to the supply of sandy soil. As far as the Binhai New Area is concerned, the sandy soil is mainly transported from Caofeidian, which is affected by the protection of the source of materials and the safety of maritime transportation. Large, Difficult to Guarantee Supply

[0005] The second method is to use the shallow vacuum preloading method to artificially lay the board, and to pre-reinforce the dredging soft soil with a certain thickness on the surface, so that it has the ability to carry construction machinery for deep treatment, and the cost will increase by 60 to 70 yuan per square meter. The construction period will be increased by 2 to 3 months

These two methods not only have a long construction period and high cost, but also have many potential safety hazards. The construction workers may fall into the mud and cause danger. Most of the sandy soil transport ships are inland river ships, which have low resistance to sea wind and waves, and ship crashes and fatal accidents occur frequently.

Images