冰盖对南水北调中线工程渠道作用力物理模拟试验研究  

Physical simulation-based experimental study on acting force from ice-cover on canal of the South-to-North Water Diversion Middle Route Project

作　　者：侯倩文 冯晓波[1] 李志军[2] 夏富洲[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《水利水电技术》2018年第2期63-69,共7页Water Resources and Hydropower Engineering

基　　金：国家科技支撑计划课题(2015BAB07B04);国家自然科学基金委项目(51579028)

摘　　要：为探究冰盖对南水北调中线工程渠道边坡作用力的产生过程和作用规律,通过低温环境实验室对模拟渠道进行了淡水冻结以及淡水冰升温试验。研究发现,冻结期冰盖厚度随着气温降低而持续增长的同时,冰力也在随之变化。但由于冻结期内冰底水冻结成冰的相变体积膨胀产生的压力与冰盖因冷缩对边坡产生的拉力相抵消,导致冰力对边坡的影响较小,几乎可以忽略。虽然升温期冰温呈上升趋势,但在冰底温度低于冰点温度期间,冰仍继续缓慢增长,冰盖热膨胀力明显上升,直至冰层内部温度梯度接近消失,冰温接近冰点温度。之后,随着气温的进一步升高,冰盖进入融化相变,冰力开始下降。研究成果对于渠道冰期安全运行和冰盖对渠道边坡作用机理的研究具有一定参考价值。In order to explore the formation process and the action law of the acting force from ice-cover on the slope of the canal of the South-to-North Water Diversion Middle Route Project,the experiments of freshwater freeze and temperature rise of freshwater-ice are carried out through the simulation made on the canal in a low-temperature environmental laboratory. The study finds out that the thickness of ice-cover continuously increases along with the decrease of temperature,while the ice force changes thereupon as well. However,due to the mutual counteraction between the pressure from the phase-transitional volumetric swelling caused by the ice frozen from the water under ice and the tensile force caused by the ice-cover due to cold shrinkage during frozen period,the impact from the ice force is less,which can almost be neglected. Though the ice temperature during temperature rise period presents a rising trend,the ice is to slowly increase during the period of that the temperature under ice is lower than the freezing-point temperature,while the thermal swelling force significantly increases until the near-disappearance of temperature gradient inside of the ice layer,namely,the ice temperature approaches to the freezing-point temperature. After that,the icecover comes into the melting phase-transition and the ice force begins to decline along with the further increase of the temperature. The study result has a certain referential value for the study on safe operation of canal during ice-period and the mechanism of the action from ice-cover on the slope of canal.

关 键 词：冰盖 膨胀力 渠道 边坡 南水北调中线工程 

分 类 号：TV698.26[水利工程—水利水电工程]