摘要
通过加入聚乙烯醇(PVA)纤维实现对混凝土加固,深入分析了PVA纤维引起的混凝土力学特性变化及其变形机制,最后开展了显微增强机理方面的研究。研究结果表明:PVA纤维混凝土在测试过程中不同时间段内形成了具有不同变化特征的应力-应变曲线。纤维含量并不是越多越好,根据不同的纤维长度分别存在一个合适的掺量,9 mm以内的纤维最佳掺入量是0.75%,长度12 mm的纤维最佳掺入量则是1%。随着纤维长度发生变化后,混凝土无侧限抗压强度也存在明显差异,纤维长度为6 mm时达到了最大无侧限抗压强度。PVA纤维在混凝土中形成了充分包裹状态,在水泥发生凝结硬化的过程中产生收缩作用,从而限制了混凝土的运动,使整体韧性获得显著提升。
The composite is strengthened by adding polyvinyl alcohol(PVA)fiber.The change of concrete mechanical properties and its deformation mechanism caused by PVA fiber were deeply analyzed.Finally,the micro-strengthening mechanism was studied.The results show that the stress-strain curves of PVA fiber reinforced concrete with different variation characteristics are formed in different time periods during the testing process.Fiber content is not the more the better.There is an appropriate amount according to different fiber lengths.The optimal content of fibers within 9mm is 0.75%,and the optimal content of fibers with a length of 12mm is 1%.With the change of fiber length,the unconfined compression strength of concrete also has obvious difference.The maximum unconfined compression strength was achieved when the fiber length was 6mm.PVA fiber forms a fully wrapped state in the concrete,and produces shrinkage in the process of setting and hardening of cement,thus restricting the movement of concrete and significantly improving the overall toughness.
作者
梁腾飞
杨瑞娟
赵伟
LIANG Tengfei;YANG Ruijuan;ZHAO Wei(School of Civil Engineering,Xi’an Transportation Engineering University,Xi’an 710300,Shaanxi,China)
出处
《高科技纤维与应用》
CAS
2021年第5期47-51,共5页
Hi-Tech Fiber and Application
基金
陕西省教育厅科研计划项目(20JK0751)
关键词
混凝土
聚乙烯醇纤维
无侧限抗压强度
机理分析
concrete
polyvinyl alcohol fiber
unconfined compression strength
mechanism analysis
