CAJ | 학술논문

基于多层次最小应变能分析，提出了确定混凝土结构D区拉压杆模型构形的一种优化方法．该方法首先借助结构拓扑优化分析拟定拉压杆模型的基本构形，并利用最小应变能参数分析确定模型的最优构形几何参数．针对小剪跨比钢筋混凝土梁，利用多层次的最小应变能分析，推导得到了其受剪分析的最优参数化拉压杆模型．研究发现：当梁的剪跨比小于1时，最优模型为“直接压杆模型”；当梁的剪跨比在1．0～2．0之间时，最优模型为“带斜拉杆的桁架模型”．依据该优化拉压杆模型，并以混凝土斜向拉杆断裂作为梁体劈裂破坏的条件，进一步推导得到了无腹筋小剪跨比梁的抗剪承载力简化计算公式．最后，通过与既有试验结果对比，表明该公式能够较好地反映剪跨比对抗剪承载力的影响．
기우다층차최소응변능분석，제출료학정혼응토결구D구랍압간모형구형적일충우화방법．해방법수선차조결구탁복우화분석의정랍압간모형적기본구형，병이용최소응변능삼수분석학정모형적최우구형궤하삼수．침대소전과비강근혼응토량，이용다층차적최소응변능분석，추도득도료기수전분석적최우삼수화랍압간모형．연구발현：당량적전과비소우1시，최우모형위“직접압간모형”；당량적전과비재1．0～2．0지간시，최우모형위“대사랍간적항가모형”．의거해우화랍압간모형，병이혼응토사향랍간단렬작위량체벽렬파배적조건，진일보추도득도료무복근소전과비량적항전승재력간화계산공식．최후，통과여기유시험결과대비，표명해공식능구교호지반영전과비대항전승재력적영향．
By means of multi-level analysis toward minimum strain-energy,an optimal approach for configuring strut-and-tie models in disturbed regions (D-regions)of concrete structures is proposed. First,a topology optimization analysis is used to determine the basic configuration,and then the op-timal geometric parameters of the model is determined using the principal of minimum strain-energy. Employing the proposed approach,optimal strut-and-tie models are obtained for the shear analysis of RC(reinforced concrete)beams with small shear span-depth ratios.It is observed that in very deep beams (λof approximately 1 .0 or less),a single direct strut between the load point and the reaction is preferred for resisting loads;while in deep beams withλbetween 1 .0 and 2.0,a truss model with diagonal ties is the optimal load-carrying mechanism.Based on the optimal strut-and-tie models,a simplified equation for shear strength is derived for RC deep beams without web reinforcement,con-sidering that the beams will approach shear failure when the diagonal ties fail in tension.Experimen-tal verification shows that the proposed equation can properly reflect the influence of the shear span-depth ratio on the shear strength.