基于离心试验的单戗立堵水下抛填砂砾石相对密度研究  

Research on the relative density of sand and gravel filled underwater based on geotechnical centrifuge tests

作　　者：刘贤才 李波[2] 沈立群 蒋丰明 史小诗 陈雷 LIU Xiancai;LI Bo;SHEN Liqun;JIANG Fengming;SHI Xiaoshi;CHEN Lei(Hubei Institute of Water Resources Security and Design,Wuhan 430070,China;Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China)

机构地区：[1]湖北省水利水电规划勘测设计院,湖北武汉430070 [2]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010

出　　处：《岩土工程学报》2024年第S01期239-243,共5页Chinese Journal of Geotechnical Engineering

基　　金：中央级公益性科研院所基本科研业务费项目(CKSF2023327/YT);国家自然科学基金项目(52208329)。

摘　　要：水下抛填散粒料常用于围堰、大坝等水利工程的建设,抛填体的相对密度直接决定了工程的变形和稳定性。以汉江某水电站大坝工程的单戗立堵水下抛填为原型条件,基于长科院CKY200大型岩土离心模型试验平台,研制了离心场中单戗立堵水下填筑试验装置,研究散粒料级配、抛填水深、上部堆载高度等影响因素下抛填体相对密度的分布规律。试验结果表明,水深12 m条件抛填平均相对密度约为0.27~0.36,抛填体上部再施加14.3 m上覆堆载后可增大至0.52~0.68,水下抛填密度受砂砾石颗粒级配影响较大,当级配良好时,水下抛填相对密度较大,可达到中密—密实状态,而级配不良时,为松散—中密状态;抛填深度越大,由于抛填料的压重而使得中下部相对密度增大;当抛填体上部施加竖向均布荷载作用时,抛填体尤其是较浅区域的相对密度显著提高。研究成果为充分利用当地散粒体材料进行水下抛填工程的设计和施工提供依据。Underwater dumping and filling of loose particles is often used in the construction of water conservancy projects such as cofferdams and dams.The compactness of the backfill directly determines the deformation and stability of the project.Experimental and theoretical research was conducted under the prototype condition of a hydropower station dam project with underwater filling in the Han River.Based on the CKY200 large-scale geotechnical centrifuge model test platform of Changjiang River Scientific Research Institute,a single embankment vertical blockage underwater filling test device in a centrifuge field is developed.Using this experimental device,the distribution laws of the compactness of the dumping body under the factors such as the gradation of loose particles,the depth of dumping and filling and the height of upper loading are studied.When the water depth is 12 meters,the average relative density obtained by underwater filling is about 0.27~0.36,and increases to 0.52~0.68 for an additional 14.3 m overlying load.The particle size distribution of sand and gravel plays an important role in the underwater filling density.When the particle gradation of the filling materials is good,the underwater filling materials have a higher compactness,which can reach a dense state.When the gradation is poor,the compactness is lower.The greater the depth of filling,the greater the compactness formed.When the vertical compression is applied to the upper part of the backfill,the compactness of the backfill,especially in shallow areas,is significantly improved.The research results provide a basis for the design and construction of underwater dumping and filling projects,especially for fully utilizing the local granular materials.

关 键 词：水利工程 水下抛填密度 离心试验 砂砾石 

分 类 号：TU47[建筑科学—结构工程]