Evaluation, performance and design of concrete liquid containing structures

混凝土含液结构物(CLCS)被广泛应用于水、石油、液化天然气、化学流体和各种形式的废物等液体和类液体材料的储存。地面支撑式储罐的使用更为普遍，因为它们在设计和建造上都很简单。此外，它们还能更好地抵抗静水压力和地震荷载。这些结构被认为是生命线设施，它们在裂缝和渗漏控制方面的功能性能具有重要意义。随着储油罐的数量和尺寸多年来不断增加，储油罐的重要性也越来越大，有必要更好地了解它们在不同负载条件下的行为。加拿大的设计标准没有直接针对CLCS的结构设计，这导致了这类设施的设计不一致。此外，对于这一重要的广泛类别的结构，设计标准之间也存在很大的不一致。这主要是由于对这些结构在静力和地震荷载下的行为缺乏了解。对于规范和标准中这方面的一些规定的有效性，设计工程师之间存在重大分歧。最具争议的问题之一是关于不同储罐结构和几何形状的响应修正系数(R)的值，例如在地震载荷下的柔性和非柔性基础储罐。迄今为止使用的R值本质上是经验性的。使这些因素合理化的唯一方法是通过分析和实验测试。拟议的研究研究的主要目标是为混凝土储罐制定合理的设计程序，以确保安全的防渗漏结构。本课程将探讨含液体结构的水密性概念。为了研究地震渗漏问题，对具有不同连接细节的圆形储罐全尺寸底板-墙体连接部分的试件进行了试验研究。这些标本在反转的情况下 循环加载将同时接受液体压力和渗漏试验。 通过在实际混凝土施工过程中安装仪器，评价混凝土在温度和收缩作用下的性能。分析研究包括使用严格的有限元方法评估矩形和圆形储罐的动力性能，该方法能够在三维域中考虑流体-结构-土壤相互作用和材料非线性的影响。预计这项研究计划将提供一个框架，以了解CLCS的行为，以满足安全、适用性、建造、维护成本和设计标准。这一框架将有助于制定加拿大的CLCS设计指南。

Concrete liquid containing structures (CLCS) are extensively used for the storage of liquid and liquid-like materials including, water, oil, liquefied natural gas, chemical fluids, and wastes of different forms. Ground-supported tanks are more common in use because of their simplicity in design and construction. In addition they provide better resistance against hydrostatic and earthquake loading. These structures are considered as lifeline facilities, and their functional performance in terms of crack and leakage control is of significance. As numbers and sizes of storage tanks have increased over the years, so have their importance and the need to better understand their behavior under different loading conditions.Canadian design standards do not directly address the structural design of CLCS and this has led to inconsistency in design of such facilities. Also, there is a great deal of inconsistency among the design standards for this important broad class of structures. This is mainly due to the lack of understanding of the behaviour of these structures under static and seismic loading. There is significant disagreement among design engineers on the validity of some of the provisions in codes and standards in this regard. One of the most controversial issue is related to the values used for the response modification factor (R) for different tank configurations and geometry such as for flexible and non-flexible base tanks under seismic loading. The R-values used to date are empirical in nature. The only way to rationalize these factors is by analytical and experimental testing.The main objective of the proposed research study is to develop a rational design procedure, for concrete tanks that assures a safe leak resistant structure. The concept of water-tightness in liquid containing structures will be investigated. To investigate the seismic induced leakage problem, an experimental study will be conducted on specimens that are representative of full scaled base slab-wall connection portion of circular tanks with different connection details. These specimens while under reversed cyclic loading will be simultaneously subjected to liquid pressure and leakage tests. It is also intended to evaluate the performance of CLCS under temperature and shrinkage effect by installing instruments in actual CLCS while under construction. The analytical study include evaluating the dynamic behavior of both rectangular and circular tanks using a rigorous finite element method capable of including the effect of fluid-structure-soil interaction as well as material non-linearities in a three dimensional domain. It is expected that this research program will provide a framework to understand the behavior of CLCS to meet safety, serviceability, construction, maintenance cost, and design standards. This framework will be useful towards the development of Canadian design guides for CLCS.