水科学进展
水科學進展
수과학진전
2009年
4期
572-577
,共6页
茅泽育%赵雪峰%胡应均%刘颖
茅澤育%趙雪峰%鬍應均%劉穎
모택육%조설봉%호응균%류영
武开河%横向冰缝%冰坝%形成机理%冰盖
武開河%橫嚮冰縫%冰壩%形成機理%冰蓋
무개하%횡향빙봉%빙패%형성궤리%빙개
mechanical icE-cover breakup%transverse crack%ice dam%mechanical principle%icE-cover
春季随着流量或水位增加,冰盖底部受水流上举力作用发生弯曲,首先在岸壁附近形成纵向冰缝,破坏冰盖与岸壁的冻结,导致冰盖体中间部分与岸壁脱落分离.采用弹性基础梁的理论及计算方法,通过对冰盖体弯矩及弯曲应力分析,针对平面弯曲和垂直弯曲两种弯曲形式导致冰盖体横向冰缝形成机理进行了研究,并提出了横向冰缝间距的计算表达式.计算结果得到了实测资料的验证.研究结果表明,横向冰缝间距与开河初期冰盖宽度、厚度、冰的抗弯强度及地貌特征有关.
春季隨著流量或水位增加,冰蓋底部受水流上舉力作用髮生彎麯,首先在岸壁附近形成縱嚮冰縫,破壞冰蓋與岸壁的凍結,導緻冰蓋體中間部分與岸壁脫落分離.採用彈性基礎樑的理論及計算方法,通過對冰蓋體彎矩及彎麯應力分析,針對平麵彎麯和垂直彎麯兩種彎麯形式導緻冰蓋體橫嚮冰縫形成機理進行瞭研究,併提齣瞭橫嚮冰縫間距的計算錶達式.計算結果得到瞭實測資料的驗證.研究結果錶明,橫嚮冰縫間距與開河初期冰蓋寬度、厚度、冰的抗彎彊度及地貌特徵有關.
춘계수착류량혹수위증가,빙개저부수수류상거력작용발생만곡,수선재안벽부근형성종향빙봉,파배빙개여안벽적동결,도치빙개체중간부분여안벽탈락분리.채용탄성기출량적이론급계산방법,통과대빙개체만구급만곡응력분석,침대평면만곡화수직만곡량충만곡형식도치빙개체횡향빙봉형성궤리진행료연구,병제출료횡향빙봉간거적계산표체식.계산결과득도료실측자료적험증.연구결과표명,횡향빙봉간거여개하초기빙개관도、후도、빙적항만강도급지모특정유관.
During the river-ice breakup, the longitudinal cracks near banks are firstly formed due to the runoff increase, resulting in the detachment of central part of ice cover from both banks.Subsequently, as a result of horizontal bending or vertical bending of ice cover the transverse cracks will be further formed, and the continuous icE-cover is finally fractured into floes with cerain sizes.Based upon the theory and calculation method of elastic-foundation, the mechanism of transversE-crack formation is fully investigated.By means of studying on the bending moment and bending stresses of ice cover, the analytical expressions of the crack-spacing due to both horizontal bending and vertical bending are presented, and validated with the field measurements.The study indicates that the transversE-crack spacing depends on the icE-cover width, thickness, bending strength and topography.