结合性质和WUHPC-NC梯度混凝土曲强度的有限元分析
Ziyang Tian1, Rui Ma1,2, Daosheng Sun1,2
1School of Materials and Chemical Engineering, Anhui Jianzhu University, Hefei 230022, China.
Materials (Basel, Switzerland)
|May 27, 2023
概括
这项研究表明,将白色超高性能混凝土 (WUHPC) 作为普通混凝土 (NC) 的外部层,显著提高了结构性能. 梯度WUHPC-NC结构显示了更好的粘合和屈曲强度, 1:4的WUHPC厚度比率是最有效的.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 混凝土技术 混凝土技术
背景情况:
- 超高性能混凝土 (UHPC) 与普通混凝土 (NC) 相比,提供了优越的机械性能和耐久性.
- 在NC外部涂上 UHPC 薄层,可以创建梯度结构,提高性能和耐腐蚀性,同时减轻与散装 UHPC 相关的问题.
研究的目的:
- 研究由白色超高性能混凝土 (WUHPC) 和普通混凝土 (NC) 组成的梯度混凝土结构的粘合性能和柔性性能.
- 为了确定最佳的WUHPC厚度和准备间隔,以提高结构完整性.
主要方法:
- 准备不同强度的WUHPC,并建造27个梯度WUHPC-NC标本,具有不同的WUHPC强度和0,10或20小时的间隔时间.
- 使用四点曲方法测试15个镜梯度样本 (100 × 100 × 400毫米),以评估WUHPC:NC比例为1:1,1:3和1:4的曲性能.
- 开发有限元模型来模拟不同厚度的WUHPC梯度混凝土结构中的裂纹行为.
主要成果:
- WUHPC-NC的粘合性能在最小间隔时间时最强,在0小时时达到最大1.5MPa.
- 纽带强度最初增加,然后随着WUHPC和NC之间的强度差异减少而减少.
- 在WUHPC:NC厚度比分分别为1:4,1:3和1:1的情况下,观察到89.82%,78.80%和83.31%的屈曲强度改善.
- 1:4的WUHPC厚度比在控制裂传播方面被证明是最有效的.
结论:
- 使用WUHPC作为NC的外部层的梯度结构在粘合和屈曲强度方面提供了显著的改进.
- 间隔时间为0小时,WUHPC与NC厚度比为1:4是最大限度地提高结构性能的最佳选择.
- 有限元分析支持实验发现,表明在裂开始点具有最小弹性应变的区域更容易发生裂.
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