水压和波浪荷载作用下钢圆筒护岸结构变形研究

Deformations of steel cylinder revetment structures under water pressures and wave loads

针对水压和波浪荷载作用下大直径钢圆筒护岸结构的受力和变形特性,开展了离心模型试验研究,分析了耦合荷载作用下的筒体位移和转角,采用PIV技术分析了土体的流动机制。试验结果表明:在开挖施工期,土体孔压迅速上升,开挖完成后孔压逐渐趋于平缓,但是孔压的变化具有迟滞性,开挖完成一段时间后土体孔压才能保持平稳;随着开挖施工的进行,筒体发生向陆侧的旋转,在开挖进行旋转速度最快,开挖完成后转角变化逐渐趋缓,筒体最大转角为0.32°,最大水平位移为358 mm,方向指向陆侧;在筒体旋转的影响下,地基土发生显著的水平位移,但当距筒的距离超过30 m后,土体的位移较小可忽略不计。总的来说,筒体在施工期位移和变形较小,未发生倾覆和滑移破坏,表明采用该结构能够满足工程要求。

The centrifugal model tests are conducted to investigate the stress and deformation characteristics of large-diameter steel cylinder revetment structures under water pressures and wave loads.The displacements and rotation angles of the cylinders under coupled loads are analyzed,and the flow mechanism of the soils is analyzed using the PIV technology.The test results show that during the excavation construction period,the pore pressures of the soils increase rapidly,and after excavation is completed,it gradually tend to be flat.However,the variation of the pore pressures has a hysteresis,and the pore pressures of the soils can only remain stable after a period of time after excavation is completed.As the excavation construction progresses,the cylinders rotate towards the land side,with the fastest rotational speed during excavation.After the excavation is completed,the angle change gradually slows down,with the maximum angle of 0.32°and the maximum horizontal displacement of 358 mm towards the land side.Under the influences of the rotation of the cylinders,significant horizontal displacements occur in the foundation soils,but when the distance from the cylinders exceeds 30 m,the displacements of the soils are relatively small and negligible.Overall,the displacements and deformations of the cylinders during the construction period are relatively small,and there is no overturning or obvious sliding failure,indicating that the use of the steel cylinder structures can meet the engineering requirements.