Dynamic Variations Of Subsurface Engineering Geological Environment On The Subaqueous Delta Of Yellow River, China

The dissertation was relied on the project of National Nature Science Foundation Project Formation and failure of hard crust on the subaqueous delta of Yellow River(Contract No. 141720888), and objective to research dynamic variation of engineering geological environmental factors i.e., topographic and morphologic features, composition and structure, physical and mechanical properties on the subsurface of Yellow River Delta, that was induced by wave loading action.Because of the engineering geological happening, the magnitude losing have often taken place on the process of design actualizing and engineering building practicality running though the designing is provided with engineering geological investigation measure of the field on engineering exploitation activity of the Subaqueous Delta of Yellow River. It occurred many times on the ocean of Shengli Oil Field that driving piles were defeated, artesian well flat roof leaned, oil transport pipe brook and oil leaked in the year of 1984, 1987, 1994 and 1998. It wasn't be obviated by man-made error and dynamic variations of engineering geological environment on the Subaqueous Delta that these geological hazard events occurred. Especially in the extreme of marine condition, the element of engineering geological environment was acutely variation in time and space. It is difficult to design a series invariable mechanics index of soil for designer adoption in a plan constructed engineering field. The dissertation will want to answer this unsolved question so for. It is one point of the dissertation.The dissertation research question belongs to the response of soil changing induced by dynamic wave load in the interacted area of soil and wave. So for, because of the restriction of experiment boundary condition that different original condition and over ideal theorization model that is mentioned in the preface, it is imminence needs to understand the changing of reality soil on the true wave loading in true time and space so that validated and lead next research in theory and simulation. The suitable study area that is natural laboratory and has representative will be selected in the dissertation, a series tests of in-site and laboratory have been carried through in the year of 1999 and 2002, the response process of soil in wave load are tried to be disappeared. This is the other one point of the dissertation.In the preface, review on relative research fields was given, included reviews of sea bed dynamic reaction to wave action research and engineering geological environment research of subaqueous delta of Yellow River, brief instruction about the thesis's idea was presented also. The body of dissertation can be divided into 12 chapters. The chapter 1 resumed the engineering geological environment of subaqueous delta of Yellow River, China. The chapter 2 instructed field work, including content, method, procedure and results. The conducted work in field contained case study area selection, topo survey, sample collection for grain size and mineral composition analysis, bore hole drilling and catching undisturbed soil samples for soil test and microstructure observation, portable cone penetration test, cone penetration test, dynamic penetration test, vane shear test, soil vibration test and hydrodynamic measurement. The chapter 3 instructed laboratory work, including test content, method and results. The lab tests contained soil dynamic triaxial test, X ray diffraction, scanning electronic microscope observation, grain size analysis and routine soil tests. From Chapter 4 to Chapterl 1, a serial of comparable methods were adapted to analyze the obtained results in Chapter 2 and Chapter 3, in order to describe quantitatively the changing of engineering geological environmental factors with time and space that is induced by different waveloading action, including reaction of topo and morphologic features to hydraulic condition, reaction of grain size and mineral composition to it and reaction of static and dynamic mechanical index to it. The Chapter...