CAJ | 학술논문

构建了顶板底部直线布置体外预应力筋加固盖板涵的计算模型，利用盖板涵加载变形前后的几何关系，探讨体外预应力筋应力增量与梁体挠度及混凝土压应变的关系，推导出了铁路运营阶段体外预应力加固盖板涵体外筋应力增量的表达式。可用该式计算在三分点荷载、均布荷载和集中荷载作用下用跨中挠度及混凝土压应变表达的体外筋应力增量。通过室内试验和相关文献验证了本文表达式的正确性，可为体外预应力加固盖板涵结构设计提供指导。
구건료정판저부직선포치체외예응력근가고개판함적계산모형，이용개판함가재변형전후적궤하관계，탐토체외예응력근응력증량여량체뇨도급혼응토압응변적관계，추도출료철로운영계단체외예응력가고개판함체외근응력증량적표체식。가용해식계산재삼분점하재、균포하재화집중하재작용하용과중뇨도급혼응토압응변표체적체외근응력증량。통과실내시험화상관문헌험증료본문표체식적정학성，가위체외예응력가고개판함결구설계제공지도。
A model of a slab-culvert strengthened with external prestress in the bottom was established. T he culvert deformations before and after the loading were investigated. T he relationship among the stress increment in prestressing strands,the deflection and the compression stress in concrete was studied. An expression for this stress increment in railway operation stage was deduced. T he expression can be used to calculate the mid-span deflection and the stress increment in prestressing strands in the case of three-point loading,uniform loading or concentrated loading. T his expression proved correct through lab test and previous references,and it can provide guidance for culvert structure strengthened w ith external prestress.