This study deals with the identification of the mechanical behavior of chemical anchors embedded in masonry walls. 108 pull-out tests are carried out in five types of masonry walls built with clay brick or vertically perforated units with cement mortar. Different parameters are taken into account: embedment depths, masonry type, anchor position (injection either in brick units or in mortar joints). The axial load capacity and the failure mode are observed for each test. The results are examined by means of elastic and plastic models assessing the efficiency of anchors installed in headers, stretchers or mortar joints. The anchors injected in mortar joints are shown to have much greater pull-out capacity than that found for anchors in bricks. Passing from 90 to 160 mm of embedment depth, a minimum increase by 40% of pull-out strength is observed. The most common failure modes are the sliding failure, which occurs for short anchors or weak masonry, and mixed sliding/cone failure, for long anchors or strong masonry. An analytical model is proposed to design anchors in order to avoid or at least to limit brittle masonry failures and to identify the field of application of uniform stress models.

中文翻译：

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安装在砌体墙中的强度锚栓的试验拔出试验和设计指示

这项研究涉及识别嵌入砌体墙的化学锚的机械性能。在用粘土砖或水泥砂浆垂直穿孔单元建造的五种砌体墙体中进行了 108 次拉拔试验。考虑了不同的参数：嵌入深度、砌体类型、锚固位置（注入砖块或砂浆接缝）。观察每个测试的轴向载荷能力和失效模式。结果通过弹性和塑性模型进行检查，评估安装在集管、担架或砂浆接缝中的锚栓的效率。在砂浆接缝中注入的锚栓显示出比砖中的锚栓具有更大的拉拔能力。从 90 到 160 毫米的嵌入深度，观察到至少 40% 的拉拔强度增加。最常见的破坏模式是滑动破坏，发生于短锚或弱砌体，以及混合滑动/锥体破坏，发生于长锚或强砌体。提出了一种分析模型来设计锚，以避免或至少限制脆性砌体破坏，并确定均匀应力模型的应用领域。