In-plane Performance of Concrete Masonry Shear Walls

剪力墙是结构砖石结构和其他类型建筑中的基本结构部件，可以抵抗风或地震造成的横向荷载。在重大地震事件中，剪力墙负责保持结构完整性，防止建筑物完全倒塌，即使其他墙或非结构构件倒塌也是如此。因此，对这些结构构件进行高效、安全的设计是非常重要的。拟议研究计划的总体目标是通过开发适用于各种砌体形式的改进的面内剪切模型，为砌体剪力墙的设计和加固提供更好的指导。拟议的研究是多方面的，通过试验和分析研究部分解决剪力墙结构设计的效率问题。这两个部分将同时进行，因为实验工作的结果将影响和加强分析工作，反之亦然。试验工作将用于利用已建立的准静态和动力试验能力来探索剪力墙性能的各种影响因素。实验部分还将结合使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势在于能够在整个感兴趣的区域内观察运动和应变，而不是在仪器所在的有限数量的特定位置观察。非接触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。用钢纤维灌浆和聚氨酯泡沫塑料作为芯层填料加固无筋混凝土砌块墙体也将进行试验研究。还将使用有限元分析对实验结果进行数值模拟。分析工作的重点是建立新的方程，通过将钢筋混凝土的方法，如修正的压力场理论(MCFT)和剪切摩擦，首次应用于未配筋和部分灌浆的砖混结构，从而更有效地反映砌体剪力墙的性能。基于剪切摩擦或MCFT的配筋砌体抗剪设计方法很有吸引力，因为与传统的经验模型相比，该方法建立在全面、合理的理论基础上，应具有更广泛的适用性。用随机和概率方法对现有的各种用于预测砌体面内抗剪强度的公式和新的公式的可靠性和安全水平进行了评估。总体而言，这项开创性的研究将实验工作中的创新测量系统与分析中的新方法相结合，将大大有助于从根本上了解砌体剪力墙的行为，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、承包商和包括政府在内的基础设施所有者。

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.