摘要
浆砌石渠道在长期的运行过程中,受外界冻融作用,水泥砂浆易产生劣化效应,影响其力学特性和服役寿命.考虑到冻融作用对水泥砂浆力学性能的劣化效应,结合红旗渠工程,利用ABAQUS有限元软件,建立总干渠渠段精细的三维有限元模型,并采用当量冻融循环次数的概念,计算得出运行54 a的红旗渠的劣化程度,分析了渠道在设计地震作用下的动力响应情况.计算表明:该工程渠道在底板与边墙交接处出现应力集中.考虑劣化效应后,渠顶相对位移变大,结构最大压应力与最大拉应力均变小,但相应的抗拉强度与抗压强度也随之降低.渠道承载力安全系数变小,结构整体性将会受到破坏,结构抗震能力显著下降.底板与边墙交接处是渠道的薄弱部位,在结构设计和安全运行监测时应给予足够重视.
Due to freeze-thaw effect,cement mortar is prone to be deteriorated,which affects its mechanical properties and service life in the long running process of slurry masonry channel.Considering the effect of freeze-thaw on the mechanical properties of cement mortar in the Hongqiqu project,a finite element model of channel was established by the finite element software of ABAQUS.In addition,the concept of the number of equivalent freeze-thaw cycles was used to calculate the degree of degradation of the Hongqiqu project after 54 years'operating and to study the dynamic response of the channel under the design seismic action.The results show that the stress concentration occurs at the junction of the floor and wall.After considering the degradation effect,the relative displacement of the Channel Top becomes bigger while the maximum compressive stress and tensile stress of the structure become smaller,while the corresponding tensile strength and compressive strength also reduces gradually.When the safety factor of bearing capacity becomes smaller,the structural integrity will be destroyed and structural aseismic capacity will drop significantly.The junction of the floor and wall is the weak part of channel,so more attention should be paid to in the design of the structure and the monitoring of safe operation.
作者
姚皓铮
沈振中
马福恒
胡江
YAO Haozheng;SHEN Zhenzhong;MA Fuheng;HU Jiang(College of Water Conservancy&Hydropower Engineering,Hohai Univ.,Nanjing 210098,China;Nanjing Hydraulic Research Institute,Nanjing 210029,China)
出处
《三峡大学学报（自然科学版）》
CAS
北大核心
2020年第2期7-11,74,共6页
Journal of China Three Gorges University：Natural Sciences
基金
国家自然科学基金/雅砻江联合基金项目(U1765205)
国家自然科学基金青年项目(51609073)。
关键词
冻融劣化
水泥砂浆
浆砌石渠道
当量冻融循环
抗震安全分析
薄弱部位
freeze-thaw degradation
cement mortar
slurry masonry channel
equivalent freeze-thaw cycle
seismic safety analysis
weak parts
