多选题
发布日期:2022-07-06
凌汛险情
水工隧洞的塌方
脉动压力、空化、空蚀
表面损坏
压力脉动即脉动压力,它就是压力作用于被作用对象上并不均匀,在某个部位有较集中的或是较大的压力,且这种压力单次持续的时间不长,有可能呈现一定的周期性。
路基、堤坝和河岸等边坡或山坡的坍塌现象。形成原因常为边坡过陡、土内水分增大、岩石风化及地震、火山爆发的影响等,和边坡或山坡的岩层构造也有关系。严重时可使交通中断或水流不畅,会造成人员伤亡和财产损失。
凌汛,俗称“冰排”。冰凌堵塞河道,对水流产生阻力而引起的江河水位明显上涨的水文现象。水面结冰的河道,上游河冰先融,下游河道尚未解冻,易出现“凌汛”。主要受气温、水温、流量与河道形态等几方面因素的综合影响而形成,可能导致堤防溃决,洪水泛滥成灾。中国北方的河流,如黄河、黑龙江、松花江,在冬季的封河期和春季的开河期都有可能发生凌汛。黄河凌汛洪水在发生频次和规模上远较其他地区为高,往往造成较大灾害。凌汛期一般需采取破冰措施,防漫堤决口,酿成灾害。(概述图参考来源:)
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