Analysis Of The Static & Dynamic Deformation And Strength Parameters And Research On Pore Pressure Of Seabed Subsoil

There are extensive deep soft soil in coastal areas in eastern China. Seabed subsoil soft soil first has poor engineering property and permeability, low shear strength, high compression and water content, and has structural characteristic. As social progress and fast economic development, a lot of buildings and structures are priority of establishment or will build there, such as coastal oil drilling platform, port, dock, oil storage tank and ordinary industrial and civil construction. The safety and stability of these structures put forward new studies and research direction to geotechnical engineering.Up to the present, There are some studies of seabed subsoil. Because of differences of regions and key researches, there are not systematic organization and further studies of seabed subsoil yet. This text is about statistics and analysis on the basis of information collection of subsoil including silt, silty soil, clay, silty clay, sand, completely weathered granite and strong weathered granite and so on. The engineering data are from Caofeidian in Tanghai County of Tangshan City, Rudong in Nantong of Jiangsu Province, Ningde and Fuqing in Fujian coast, Taishan and Yangjiang in the Pearl River Delta, Huanghuagang in Cangzhou of Hebei Province and Hongyanhe in Dalian of Liaoning Province and so on.The content of this text includes:(1) On the basis of Duncan-Chang model and equivalent linear model, research on static and dynamic module coefficient K, Kd of seabed subsoil.lt is proposed that the extent and the relationship of K, Kd of different soil types. Summary on relationship between K,Kd,strength parameters f,fd and dry density pd has been made.(2)Statistic and analyse static and dynamic stength parameters of seabed subsoil. Discuss the characters of the static stength parameters by two ways to express. Finish static and dynamic strength extent of different soil types. Comparing between normalized dynamic shear stress and failure vibration frequency,find out influence of different soil types and regions elements on dynamic strength.At last, analyse proportional relation between static and dynamic stength parameters of the same soil type.(3)Research on quivalent dynamic shear modulus and damping ratio related to the amplitude of dynamic shear strain. Contrast quivalent dynamic shear modulus and damping ratio of different soil types.A reference range of the modulus are proposed. In this range the normalized dynamic equivalent shear modulus and dynamic damping ratio are related to the amplitude of dynamic shear strain.Comparing with other studies both at home and abroad.(4)Fit and analyse the pore pressure curve of seabed subsoil. Research on pore presure development under dynamic loads of fine sand, coarse sand, eluvial soil and silty soil. Analyse the characters of pore pressure development. Fit the formulars of pore pressure and determine the most applicable formular for different soil types.Study on whether pore pressure reaches confining pressure under isotropic and anisotropic consolidation.