CAJ | 학술논문

基于数值模拟和以往研究,分析了不同强弱约束状态下的FRP约束混凝土行为.分析结果表明:(1)约束混凝土应力-应变曲线根据强弱约束状态不同而发生变化,处于强约束条件下的混凝土,极限强度大于无约束混凝土强度,对于加固量较小的弱约束混凝土,破坏时的应力值等于或者小于无约束混凝土的强度;(2)计算非圆形截面的约束应力、约束刚度、极限约束应力时要考虑形状等效系数kse,约束混凝土极限状态下的FRP断裂应变小于FRP极限拉应变,对于混凝土圆柱,FRP断裂应变可等效为环形劈裂试验值,对于非圆形截面,需计入形状等效系数kse的影响;(3)定义极限约束应力与无约束混凝土强度比值为约束比,约束比决定混凝土强弱约束状态.通过对收集到的试验数据进行回归,提出了强弱约束判断准则.
기우수치모의화이왕연구,분석료불동강약약속상태하적FRP약속혼응토행위.분석결과표명:(1)약속혼응토응력-응변곡선근거강약약속상태불동이발생변화,처우강약속조건하적혼응토,겁한강도대우무약속혼응토강도,대우가고량교소적약약속혼응토,파배시적응력치등우혹자소우무약속혼응토적강도;(2)계산비원형절면적약속응력、약속강도、겁한약속응력시요고필형상등효계수kse,약속혼응토겁한상태하적FRP단렬응변소우FRP겁한랍응변,대우혼응토원주,FRP단렬응변가등효위배형벽렬시험치,대우비원형절면,수계입형상등효계수kse적영향;(3)정의겁한약속응력여무약속혼응토강도비치위약속비,약속비결정혼응토강약약속상태.통과대수집도적시험수거진행회귀,제출료강약약속판단준칙.
Based on the numerical simulation and related studies,the behavior of FRP-confined concrete under powerful confinement and weak confinement is analyzed in this paper.The results show that:(1) The stress-strain curve is different according to the confinement condition whether is powerful or not.For the powerful confinement,the stress-strain curve is ascending straight line in the second stage,but it's contrary to the weak confinement confined concrete.(2) For the non-circular section,the equivalent section coefficient kse should be considered when calculate restraint stress,restraint stiffness and ultimate restraint stress.The rupture strain of FRP-confined concrete in ultimate status is less than that from flat coupon tensile test.For the confined concrete cylinder,the rupture strain of FRP can be equivalent to the value of the ring splitting test,but to the non-circular section,the influence of section shape should be considered.(3) The confinement ratio is defined as the ratio of ultimate restraint stress to concrete strength under the unconfinement condition,which is used to determine confinement condition.The criteria of powerful or weak confinement is proposed through the regression for collection test data.