本文报告了使用钢梯和聚合物条带增强件进行的实验室和3D数值模拟拉出测试的结果。这些类型的钢筋通常用于用混凝土饰面元件构造的加筋土墙中。需要进行实验室拉出测试,以确定准确和现实的拉出强度值,考虑到特定的钢筋和回填材料在不同围压下的相互作用(即,试图模拟实际加筋土墙中不同的加固层布置和荷载条件)。加固土墙的国际设计规范提供了拔出强度的默认值。然而,在许多情况下,默认值过于保守和/或未为特定钢筋类型严格指定。拉出测试可能是困难和昂贵的执行,因此对于绝大多数加筋土墙工程来说并不常见也不值得。因此,校准的数值模型可用于预测特定地点条件下的拔出响应,并进一步了解土体-加筋相互作用的机理。数值方法的细节,包括土壤-加固界面的相关方面,被描述。拉出载荷的校准数值预测示例,流离失所,并给出了土壤剪胀效应。加固的影响,显示了土壤和界面刚度。数值结果为特定类型的回填材料与加固单元之间复杂相互作用的未来建模工作提供了有用的见解。与加筋土墙的调查和/或实际设计相关。
This paper reports results of laboratory and 3D numerical modeled pull-out tests with steel ladders and polymeric strip reinforcements. These types of reinforcement are commonly used in reinforced soil walls constructed with concrete facing elements. Laboratory pull-out tests are required to determine accurate and realistic pull-out strength values considering the interaction of specific reinforcement and backfill materials under different confining pressures (i.e., trying to simulate the different reinforcement layer arrangements and load conditions in actual reinforced soil walls). International design Codes for reinforced soil walls provide default values for pull-out strength. However, in many cases, default values are too conservative and/or are not strictly specified for particular reinforcement types. Pull-out tests can be difficult and expensive to perform, thus not being common nor worth for the vast majority of reinforced soil wall projects. Consequently, calibrated numerical models can be useful to predict pull-out response under site-specific conditions, and provide further understanding of the mechanisms involved in the soil-reinforcement interaction. Details of the numerical approach, including relevant aspects of the soil-reinforcement interfaces, are described. Examples of calibrated numerical predictions for pull-out loads, displacements, and soil-dilatancy effects are presented. The influence of reinforcement, soil and interface stiffnesses is shown. Numerical results provide useful insight for future modelling works of the complex interaction between type-specific backfill materials and reinforcement element, relevant for investigation and/or practical design of reinforced soil walls.