摘要
针对斜交钢筋混凝土连续板桥中混凝土材料的损伤演化问题,本工作以丽江市某斜交桥为研究对象,通过实测数据揭示材料在动静力耦合作用下的失效机制。结果表明:斜交效应导致混凝土基体产生显著应变梯度,校验系数为0.07~0.77,裂缝宽度达0.60 mm,超过规范限值200%,凸显了传统混凝土的抗裂性与抗冲击性能不足;动力响应分析中,裂缝的动态扩展行为与结构显著的振动响应同步发生,证实材料阻尼性能缺失加剧了损伤演化。基于此,提出PVA纤维增强混凝土与橡胶基阻尼复合材料的协同改性方案:纤维通过桥接效应抑制裂缝开展,阻尼层在支座区耗散振动能量,二者共同阻断“应力集中-裂缝扩展-动力加剧”的材料级损伤链条。该研究为提升斜交桥混凝土结构的耐久性提供了材料设计新思路。
Regarding the damage evolution of concrete materials in skewed reinforced concrete continuous slab bridges,this work takes a skewed bridge in Lijiang City as the research object and reveals the failure mechanism of materials under the coupling effect of dynamic and static forces through measured data.The results show that the skewed effect causes a significant strain gradient in the concrete matrix,with the calibration coefficient ranging from 0.07 to 0.77,and the crack width reaching 0.60 mm,which exceeds the specification limit by 200%.This exposes the inadequacies of traditional concrete in terms of crack resistance and impact resistance.In the dynamic response analysis,the dynamic propagation behavior of cracks occurs synchronously with the significant vibration response of the structure,confirming that the lack of material damping performance exacerbates the damage evolution.Based on this,a synergistic modification scheme of PVA fiber-reinforced concrete and rubber-based damping composite materials is proposed:fibers inhibit crack development through a bridging effect,and the damping layer dissipates vibration energy in the support area.Together,they block the material-level damage chain of"stress concentration-crack growth-dynamic intensification".This research provides a new idea for material design to improve the durability of concrete structures in skewed bridges.
作者
母昌辉
杨建荣
MU Changhui;YANG Jianrong(Department of Civil Engineering,Faculty of Civil Engineering and Mechanics,Kunming University of Science and Technology,Kunming 650500,China;Earthquake Engineering Researching Center of Yunnan,Kunming 650500,China)
出处
《材料导报》
北大核心
2025年第S2期269-275,共7页
Materials Reports
关键词
钢筋混凝土板桥
动静力损伤
PVA纤维
阻尼复合材料
裂缝控制
材料协同效应
reinforced concrete slab bridge
dynamic and static damage
PVA fiber
damping composite material
crack control
material synergistic effect
