BARRETTE FOUNDATIONS pdf epub mobi txt 電子書 下載2025

《壁闆樁基礎》內容為:Although excavated rectangular piles, i. e., barrettes, have been extensivelyused recently, relatively few investigations have been carried out to study thefundamental behaviour of barrettes. The objectives of this book are to improvethe understanding of:l)the ground deformation and soil stress change during theinstallation of a barrette2)the mobilisation behaviour of the shaft resistance of abarrette under vertical loading. These objectives have been achieved by carryingout full-scale field tests, analytical study and three-dimensional numericalmodelling.

A new,simple and explicit plane stress analytical elastic solution was derivedand calculation charts and tables were developed for calculating the horizontalstress changes and displacements caused by the installation of a barrette. It hasbeen shown that for a long and thin barrette,stress relief and stress increase aregenerally induced in the soil around the faces and the ends of the barrette trenchduring the bentonite stage, respectively. The larger the aspect ratio (length towidth) of a barrette,the greater is the magnitude and the more extensive is theinfluence zone of the horizontal stress changes and displacements caused by theinstallation. The maximum horizontal displacement is approximately proportionalto the length of the barrette. The applicability of the proposed two-dimensionalanalytical solution to three-dimensional barrette installation problem wassubsequently examined by using a three-dimensional numerical technique. Inaddition,the loading test on a 40m deep barrette constructed at Kowloon Bay,Hong Kong provided a comprehensive case history of the soil response to barretteinstallation. It has been observed that during installation of the barrette,the totallateral pressure on the sidewalls of the barrette trench was first reduced from thetotal earth pressure at rest to the hydrostatic bentonite pressure and thenincreased to the wet concrete pressure given approximately by a theoreticalbilinear envelope. Also observed are small ground movements.