通过巴塞罗那测试,用聚烯纤维增强的混凝土的破裂后性能
Alexandre Almeida Del Savio1, Darwin La Torre Esquivel1, Joaquín M García Landeo1
1Civil Engineering Department, Universidad de Lima, Lima 15023, Peru.
Polymers
|September 28, 2023
概括
巴塞罗那方法有效地评估了聚烯纤维混凝土. 钢筋强度指数结合了纤维体积和纤维细度,准确地预测了裂后的性和残余强度.
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:
- 巴塞罗那方法为测试混凝土破裂后的行为提供了一个较小规模的替代方案,非常适合具有挑战性的建筑.
- 聚烯 (PP) 纤维越来越多地用于混凝土,因为它们的高抗拉强度和成本效益.
研究的目的:
- 研究聚烯纤维体积,纤细度和钢筋强度指数对混凝土破裂后性能的影响.
- 建立基于纤维特性的性和残余强度的预测方程.
主要方法:
- 使用巴塞罗那方法测试各种聚烯纤维体积 (0.4%,0.8%,1.2%) 和细度比率 (46.5,58.1,69.8) 的混凝土样本.
- 准备100个标本,包括一个参考混合物和10个纤维增强混合物,每个有10个复制品.
- 采用皮尔森的假设测试和散射图来分析相关性和开发预测模型.
主要成果:
- 纤维纤细度和裂纹后性能之间没有发现直接相关性.
- 纤维体积与残余强度相关,但与性无关.
- 钢筋指数 (结合体积和细度) 与性和残余强度都有显著的相关性.
结论:
- 钢筋指数是预测聚烯纤维增强混凝土破裂后性能的一个关键参数.
- 开发了四个基于强化指数的预测方程,用于设计混凝土结构.
- 巴塞罗那方法和衍生式为在实际应用中使用PP纤维增强混凝土进行表征和设计提供了有价值的工具.
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