混凝土
混凝土
혼응토
Concrete
2015年
9期
142-145,150
,共5页
陈志清%刘荣桂%蔡东升%谢桂华
陳誌清%劉榮桂%蔡東升%謝桂華
진지청%류영계%채동승%사계화
单箱三室箱梁%水化热%温度应力%数值模拟
單箱三室箱樑%水化熱%溫度應力%數值模擬
단상삼실상량%수화열%온도응력%수치모의
a single box and triple cells%hydration heat%temperature stress%numerical simulation
通过有限元软件对青弋江某特大桥单箱三室预应力混凝土零号块箱梁进行水化热研究,根据现场记录的各测点的温度值与数值模拟结果对比分析,研究了预应力混凝土零号块箱梁在分层浇筑过程中温度变化和应力变化规律。结果表明:板越厚,温度越高,温度下降越缓慢;应力发生最大的部位位于横隔板与腹板的交界表面处、人洞表面处,对于分层浇筑,新旧混凝土处的横隔板与腹板的交界处是混凝土比较容易开裂的部位,横隔板与腹板交界表面处先受拉再受压,底板应力先受压后受拉。因此可以通过加强养护、布置温度钢筋等措施来改善混凝土内部的受力性能,为类似的工程提供参考。
通過有限元軟件對青弋江某特大橋單箱三室預應力混凝土零號塊箱樑進行水化熱研究,根據現場記錄的各測點的溫度值與數值模擬結果對比分析,研究瞭預應力混凝土零號塊箱樑在分層澆築過程中溫度變化和應力變化規律。結果錶明:闆越厚,溫度越高,溫度下降越緩慢;應力髮生最大的部位位于橫隔闆與腹闆的交界錶麵處、人洞錶麵處,對于分層澆築,新舊混凝土處的橫隔闆與腹闆的交界處是混凝土比較容易開裂的部位,橫隔闆與腹闆交界錶麵處先受拉再受壓,底闆應力先受壓後受拉。因此可以通過加彊養護、佈置溫度鋼觔等措施來改善混凝土內部的受力性能,為類似的工程提供參攷。
통과유한원연건대청익강모특대교단상삼실예응력혼응토령호괴상량진행수화열연구,근거현장기록적각측점적온도치여수치모의결과대비분석,연구료예응력혼응토령호괴상량재분층요축과정중온도변화화응력변화규률。결과표명:판월후,온도월고,온도하강월완만;응력발생최대적부위위우횡격판여복판적교계표면처、인동표면처,대우분층요축,신구혼응토처적횡격판여복판적교계처시혼응토비교용역개렬적부위,횡격판여복판교계표면처선수랍재수압,저판응력선수압후수랍。인차가이통과가강양호、포치온도강근등조시래개선혼응토내부적수력성능,위유사적공정제공삼고。
The study of the hydration heat of the block zero of prestressed concrete box girder with a single box and triple cells of Qingyi River Bridge was done based on the finite element software. Base on temperature and numerical simulation results of field record-ing of each measuring point,the temperature change and stress variation of prestressed concrete box girder in a hierarchical block zero in the course of casting were analyzed. The results show that the thicker the board,the higher the temperature and more the temperature drops,the maximum stress occurs at the cross-junction of the surface of the separator and the web,also the surface of the people′hole. For the hierarchical placement,it is the old concrete crossbeam junction with the web that is easy to crack,crossbeam and web in-terface surface is under firstly tension and then bears pressure while the plate stress bears compression at first and then tension. There-fore,by strengthening the conservation,furnished temperature steel and other measures to improve the mechanical properties of con-crete. It can provide a reference for similar projects.