水流冲刷作用下软体排守护边滩失稳机理概化模型试验初步研究  

Preliminary Study on the Failure Mechanism of the Flexible Mattress Protection Beach Under the Water Flow Scouring Using Generalized Model

作　　者：魏祥龙 戴佳琦 左利钦[2,5] 陆永军 杨涵苑[2] 陆彦 黄廷杰 芦安平[6] 袁赛瑜 WEI Xianglong;DAI Jiaqi;ZUO Liqin;LU Yongjun;YANG Hanyuan;LU Yan;HUANG Tingjie;LU Anping;YUAN Saiyu(The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210024,China;The National Key Laboratory of Water Disaster Prevention,Nanjing Hydraulic Research Institute,Nanjing 210029,China;State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China;Nanjing Automation Institute of Water Conservancy and Hydrology,Ministry of Water Resources,Nanjing 210012,China;Yangtze Institute for Conservation and Development,Nanjing 210024,China;Changjiang Nanjing Waterway Engineering Bureau,Nanjing 210011,China)

机构地区：[1]河海大学水灾害防御全国重点实验室,江苏南京210024 [2]南京水利科学研究院水灾害防御全国重点实验室,江苏南京210029 [3]四川大学山区河流保护与治理全国重点实验室,四川成都610065 [4]水利部南京水利水文自动化研究所,江苏南京210012 [5]长江保护与绿色发展研究院,江苏南京210024 [6]长江南京航道工程局,江苏南京210011

出　　处：《应用基础与工程科学学报》2024年第3期773-786,共14页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(52309085,U2040219);江苏省自然科学基金项目(BK20230960);江苏省卓越博士后计划(2023ZB845);江苏省水利科学研究院自主科研经费专项资金项目(2022Z017);长江航道科技项目(Hs219003)。

摘　　要：软体排是河道与航道整治工程中广泛应用的洲滩守护结构,排体所护边滩的稳定性对排体变形及服役状态具有重要影响.水流作用下的边滩局部动力环境复杂,其失稳模式与水下自由边坡模式不同,失稳模式及产生机理有待探究.基于概化物理模型试验,对排体守护下的边滩失稳模式及形成机理开展研究.研究表明,排体守护边滩会发生牵引型与滑覆型两种失稳形式,边滩牵引型失稳所引起的排体应变响应较小,发生在排体整个冲刷周期.排尾冲刷变形累计达到一定程度后会产生偶发性的滑覆型失稳,引起边滩产生大范围滑动失稳及排体大范围沉降变形;排体守护下边滩滑覆型失稳的机理:水流冲刷引起边滩潜在滑动面下移,随边缘冲刷深度的增加,潜在滑动面与水平面的夹角不断增大,稳定性不断降低,最终导致潜在滑动面力学失稳(F_(s)<1),引起内部边滩产生大范围的滑覆型失稳.Flexible mattress is a kind of beach protection structure,which is widely used in the waterway regulation projects in the middle and lower reaches of the Yangtze River.The beach stability has a great impact on the deformation and in-situ service condition of the flexible mattress.The local hydrodynamic environment near the beach is complex,and the failure model of the protected beaches is different from the failure model of the free slopes,so the failure model and its mechanism needs a further study.In this paper,a generalized physical model experiment is carried out to study the beach failure model and its mechanism under the protection of the flexible mattress.The study results show that:(1)According to the different mechanisms of the beach collapse,there are two types of beach collapse,traction type and sliding-covering type.The strain response value caused by the traction collapse is small,and the traction collapse occurs almost in the whole experiment time.The sliding-covering type collapse is an occasional failure phenomenon caused by the accumulation of boundary condition to a certain extent,and which leads to the large-scale sliding failure of beach and the large-scale subsidence deformation of the flexible mattress.(2)The sliding-covering collapse mechanism of the protected beach can be summarized as followed:under the protection of the flexible mattress,the potential slip surface of the beach is moving down by the water flow scouring.The angle between the potential slip surface and the horizontal plane is increasing with the increasing of scouring depth.The local stability of the beach is continuously reduced,which leads to the mechanical instability(F_(s)<1)on the potential slip surface and the widespread sliding-covering type failure inside the beach.

关 键 词：软体排 航道整治 洲滩守护 崩岸 失稳机理 光纤传感 稳定性分析 

分 类 号：TV147[水利工程—水力学及河流动力学]