Investigation of the Design of Anchorage Head and Bond Length for Assessing Multistrand Anchorages

本研究计划的总体目标是改进多股锚固的安全性、设计标准和评估。为了实现这一目标，工作将集中在最关键的方面，锚头和固定锚长。该研究将结合广泛的全尺寸实验室工作和数值模拟。整体测试将包括最初的现场和实验室测试。最初的现场测试将在一些已经安装的多股锚固装置上进行，这些锚固装置具有不同的锚固头组件。随后将建造和测试两个全尺寸锚链-一个将是两股岩石锚链，另一个将是典型的四股岩石锚链。此外，还将建造锚固头试验台，以获得锚固头的刚度特性。为了研究多链锚固体对锚固头和/或固定锚固长度变化的动态响应，将建立多链锚固体的数值模型。这将被验证，然后用于提供锚固头的最佳刚度特性，适用于使用动态测试进行负载估计。最后，实验室和数值研究的结果将导致新的锚固头设计的发展，以改善这些锚固的荷载条件的评估。这将在一个类似设计的全尺寸现场锚固上进行测试。

The overall aim of this research proposal is improvement to the safety, design criteria and assessment of multi-strand anchorages. In order to achieve this, the work will focus on the most critical aspects, the anchorage head and fixed anchorage length. The research will combine extensive full-scale laboratory work with numerical modelling. The overall testing will comprise initial field and laboratory testing. The initial field testing will be carried out on a number of already installed multi strand anchorages with different anchorage head assemblies. This will be followed by the construction and testing of two full scale strand anchorages - one will be a two-strand rock anchorage and the other will be a typical four-strand rock anchorages. In addition anchorage head test rigs will be constructed in order to obtain the stiffness characteristics of the anchorage heads. A numerical model of multi strand anchorages will be developed in order to investigate their dynamic response to changes in the anchorage head and/or fixed anchorage length. This will be validated and then used to provide the optimal stiffness characteristics for an anchorage head suitable for load estimation using dynamic testing.Finally, the results from both the laboratory and numerical studies will lead to the development of a new anchorage head design with a view to improving the assessment of the load condition of these anchorages. This will be tested on a full scale field anchorages of a similar design.