Filling And Ground Treatment Technologies Of Land Reclamation And Their Applications

Land reclamation project is one of the oldest way of using ocean space. Now, a new wave of land reclamation begins with the rapid development of economy in the 21st century. This project effectively buffers the conflict between the development of coastal areas and the shortage of construction land in our country.Most of land reclamation projects in our country fill the ocean using dredged silt, and dredger fill foundation is always above seabed soft soil layer. Thence, the settlement of the foundation itself and soft layer finally result in deep and uneven land subsidence and liquefaction, which are the common technical problems we facing in land reclamation projects.This paper is supported by the first phase of No.1 south jetty project of Lanshan port in Rizhao and focus on the foundation treatment technology and filling technology which can form new land area. Firstly, a reclamation technical perspective is purposed on the base of research status at home and abroad. Seabed silt and dredger silt are gathered and the new land is divided into two areas:non-soft soil foundation mainly consisting of coarse grained soil and soft soil foundation mainly consisting of silt. Then corresponding methods are chosen to reinforce different areas. Secondly, the principle and conditions of forming silt cavity is illuminated based on the soil mechanics principle and sorting characteristics of hydraulic fill. Ultimately, On the basis of comprehensive investigation and research on engineering geology, environment and construction condition of the study area. Silt cavity reclamation fill technology are applied to the land reclamation project of the first phase of No.1 south jetty project of Lanshan port in Rizhao successfully.The main results of this study are as follows:(1) Silt cavity reclamation fill technology is adopted to form silt cavity in the study area. And silt cavity is surrounded by non-soft soil land consisting of coarse grained soil.(2) The new exploration equipment could investigate special soil layer which contains abundant and uneven distributed rubble through the improvements on the traditional equipment and drilling technology.(3) An indoor simulation testing method is established to study the influences of skin degradation on bearing properties of piles based on the research approach of pile-soil interface interaction.(4) Technical route and method which contains indoor sample preparation and on-site maintenance is established to study the deterioration of cement soil formed in corrosive site.(5) A silt stirring pumping machine has been developed and could apply in the silt cavity transfer engineering.(6) The engineering practice of the first phase of No.1 south jetty project of Lanshan port show that silt cavity reclamation fill technology could not only solve the problem of the low surface strength, large settlement and liquefaction of newly formed land after construction but also has significant social benefits and economic benefits.This research can provide reference for the similar land reclamation project.