Comparison of the behavior of PVA-ECC and normal concrete material in crack and leakage control in liquid containing structures

混凝土含液结构的开裂特性及其与漏液的关系是其设计的关键问题之一。在这个问题上的一致知识对于确保满足可服务性要求是必不可少的。以往在这方面的研究非常有限。大多数可用的文献都集中在简单静荷载下普通混凝土的典型梁截面的泄漏行为。缺乏经验数据的渗透行为的板或墙的部分组成的智能材料在组合载荷下的表现是在文献中感到。本研究旨在通过非线性有限元分析和实验两种方法来解决这一问题，通过测量受压水条件下加载试件的泄漏率作为裂缝条件和时间的函数。这一问题对于CLCS应用于城市供水、污水处理、消防、核工业等生命线设施能力具有特别重要的意义。在此类应用中，由于功能原因，裂缝和泄漏控制是主要关注的问题，而不受控制的裂缝可能导致不可挽回的后果。本研究强调的主要问题是，在包括地震在内的不同荷载作用下，安全壳脆弱区域的裂缝发展导致不可控制的泄漏。目前的设计规范没有充分解决这个问题，设计工程师在设计中保守地考虑到这一点，因此需要进行更详细和集中的调查。本研究的主要目的是评估和比较自修复ECC（工程胶凝复合材料）和普通混凝土材料在控制CLCS裂缝/泄漏方面的性能，以努力实现这类结构中最理想的水密性特性。在这种关系中，建议在代表加固容器墙的试件中引入各种加载类型和应力组合，然后对其水密性进行测试。

One of the key issues in the design of concrete liquid containing structures (CLCS) is their crackingcharacteristics and its relation to the liquid leakage. A consistent knowledge on this matter is essential to ensureif the serviceability requirements are met. The previous research conducted in this area is very limited. Most ofthe available literature is focused on the leakage behavior of typical beam sections made of normal concreteunder simple static loading. The lack of empirical data on the permeability behavior of slab or wall sectionsmade of smart material under combinations of loadings is felt in the literature. This study intends to addressthis issue both analytically, using the non-linear finite element (FE) analysis and experimentally, measuring theleakage rate in the loaded specimens under pressurized water as a function of the crack conditions and time.The issue is of particular significance for CLCS used in lifeline facility capacities such as in municipal watersupply, sewage treatment, firefighting, nuclear industry, etc. In such applications, due to functionality reasons,crack and leakage control is the main concern and an uncontrolled cracking could lead to irreparableconsequences. The major issue to be emphasized in this research is the development of cracks leading touncontrollable leakage in the vulnerable regions of the containment walls due to different loading applicationsincluding seismic. Current design codes do not address this issue adequately and it is left to design engineers toconservatively consider it in their design, thus necessitating a more detailed and focused investigation. Themain objective of this research is to assess and compare the performance of self-healing ECC (EngineeredCementitious Composites) and normal concrete material in controlling the crack/leakage in CLCS in an effortto achieve the most desired water tightness characteristics in this type of structures. In this relation, it isproposed that various loading types and stress combinations be induced in specimens representing a reinforcedcontainer wall and their water-tightness behavior be examined then.