大体积现浇抗裂混凝土施工裂缝防治研究
2021-04-01陈彦红陈季杨建新窦建瑜张扬黄钰程唐强史培新
陈彦红 陈季 杨建新 窦建瑜 张扬 黄钰程 唐强 史培新



摘 要:在大体积混凝土施工中由于大幅度温度升降引起的微应变,而导致微裂缝的产生与发展,为此,混凝土抗裂剂凭借出色的补偿收缩性能在大体积混凝土施工中得到了试验与运用。本文运用补偿收缩混凝土技术,研究添加不同浓度HME-V抗裂剂掺量(0%,4%,8%,12%,16%)的抗渗混凝土施工和易性、散热情况及力学性能,同时和掺入0.4%聚丙烯纤维的抗渗混凝土做对比研究,采用Abaqus有限元软件对隧道的顶板与侧墙施工过程中的温度场与塑性损伤进行数值模拟计算。试验结果表明,抗裂剂配制的抗渗混凝土和易性更佳,力学性能相较原始混凝土有良好的保证,并在塑性损伤及大体积散热方面有不错的表现。
关键词:混凝土;抗裂剂;坍落流动性;力学性能,温度监测;Abaqus 数值模拟
中图分类号:TU528 文献标识码:A 文章编号:1006-8023(2021)01-0105-06
Abstract:In order to control the strain caused by large temperature drop in mass concrete construction, which leads to the generation and development of micro cracks, concrete anti-cracking agent has been tested and applied in mass concrete construction with its excellent performance of compensating shrinkage. In this paper, the construction workability, heat dissipation and mechanical properties of impermeable concrete with different concentrations of HME-V anti-cracking agent (0, 4%, 8%, 12%, 16%) are studied by using the shrinkage compensating concrete technology. Meanwhile, it is compared with the impermeable concrete with 0.4% polypropylene fiber. ABAQUS finite element software is used to numerically simulate the temperature field and plastic damage during the construction of the roof and side walls of the tunnel. The test results show that the impermeable concrete prepared with anti-cracking agent has better workability, better mechanical properties than the original concrete, and has good performance in plastic damage and mass heat dissipation.
Keywords:Concrete; crack-resistant agent; slump flow; mechanical properties; temperature monitoring; Abaqus nume-rical simulation
0 引言
近年來,我国大力建设地下隧道工程,提升交通通行速度,减缓交通拥堵。随着地下工程建设迅猛发展,我国的隧道工程总里程已占据全球第一,并能成功克服各类复杂地形地质条件的束缚,隧道工程在全国范围内得到了广泛的建设运用[1-3]。然而,在隧道大量建设与使用的同时,各类工程问题及难题的出现在所难免。隧道普遍存在渗漏水、开裂和围岩破损等损坏现象。其中,隧道裂缝病害是影响隧道工程安全的关键。
隧道裂缝产生的诱因众多,而混凝土浇筑施工与养护过程中的温缩影响最为严重。……
