In-plane Performance of Concrete Masonry Shear Walls

剪力墙是结构砌体和其他类型的建筑物中必不可少的结构部件，可以抵抗风或地震引起的侧向载荷。在重大地震事件中，即使其他墙壁或非结构部件倒塌，剪力墙也负责保持结构完整性并防止建筑物完全倒塌。因此，对这些构件进行高效、安全的设计是十分重要的。提出的研究方案的总体目标是通过开发一种适用于各种砌体形式的改进的面内剪力模型，为砌体剪力墙的设计和加固提供改进的指导。提出的研究是多方面的，通过实验和分析研究组件来解决剪力墙结构设计的效率问题。这两个组成部分将同时进行，因为实验工作的结果将影响和加强分析工作，反之亦然。实验工作将用于利用已经建立的准静态和动态测试能力来探索剪力墙行为的各种影响因素。实验部分还将采用一种新的视觉测量系统，该系统改编自粒子图像测速（PIV）技术。与传统仪器（如位移传感器、应变计）相比，使用这种新型系统的优点是能够观察整个感兴趣区域的运动和应变，而不是在仪器连接的有限数量的特定位置。非接触式系统对于动态测试也是至关重要的，因为传统的测量仪器很容易损坏。试验研究了钢纤维增强浆液和聚氨酯泡沫填料对非钢筋混凝土砌块砌体墙体的加固效果。实验结果的数值模拟也将使用有限元分析进行。分析工作的重点是开发新的方程，通过应用钢筋混凝土的方法，如修正压缩场理论（MCFT）和剪切摩擦，更有效地捕捉砌体剪力墙的行为，首次用于未加固和部分灌浆砌体。基于剪切摩擦或MCFT的加筋砌体剪切设计方法具有吸引力，因为与传统的经验推导模型相比，该方法基于全面、合理的理论，应具有更广泛的适用性。本文将采用随机和概率方法，对现有的各种砌体面内抗剪强度预测方程及其可靠度和安全等级进行评估。总的来说，这项开创性的研究结合了实验工作中的创新测量系统和分析中的新方法，将对砖石剪力墙行为的基本理解做出重大贡献，从而提高加拿大和其他地方的设计标准，影响研究人员、设计师、承包商和基础设施所有者，包括政府。

Shear walls are essential structural components in structural masonry and other types of buildings that resist lateral loads due to wind or earthquakes. In significant seismic events, shear walls are responsible for maintaining structural integrity and preventing total collapse of a building even if other walls or non-structural components collapse. Thus efficient and safe design of these structural members is very important. The overall aim of the proposed research program is to provide improved guidance for the design and strengthening of masonry shear walls by developing an improved model for in-plane shear which is applicable to various masonry forms. The proposed research is multi-faceted, addressing the efficiency of structural design for shear walls through both experimental and analytical research components. These two components will be carried out concurrently since the results from the experimental work will influence and augment the analytical work and vice versa. The experimental work will be used to explore various influencing factors in shear wall behaviour using already established quasi-static and dynamic test capabilities. The experimental component will also incorporate the use of a new visual measurement system adapted from the Particle Image Velocimetry (PIV) technique. The advantage of using such novel systems in comparison to traditional instruments (e.g. displacement transducers, strain gauges) is the ability to observe movements and strains in an entire area of interest, rather than at a limited number of specific locations where the instruments are attached. Non-contact systems are also crucial for dynamic testing where traditional measurement instruments can be easily damaged. Strengthening of unreinforced concrete block masonry walls using both steel fibre reinforced grout and polyurethane foams as core-fill will also be studied experimentally. Numerical modelling of the experimental results will also be carried out using finite element analysis. The focus of the analytical work is to develop new equations that more effectively capture masonry shear wall behaviour by applying methods from reinforced concrete, such as modified compression field theory (MCFT) and shear friction, to unreinforced and partially grouted masonry for the first time. Shear design methods based on shear-friction or MCFT for reinforced masonry are attractive because, in contrast to traditional, empirically derived models, the approach is based on comprehensive, rational theory that should be more widely applicable. Various existing equations for predicting in-plane shear strength of masonry will be evaluated along with the new equations for their reliability and level of safety by employing stochastic and probabilistic methods. Overall, this ground-breaking research, which combines innovative measurement systems in the experimental work with a novel approach in the analysis, will contribute significantly to the fundamental understanding of the behaviour of masonry shear walls leading to improvement in design standards in Canada and elsewhere, impacting researchers, designers, contractors, and infrastructure owners, including governments.