保护纲要。Part 16: The monitoring of movement in historic buildings and structures

This article focuses on the phenomenon of 'bond timbers', which were commonly built into masonry walls from the late 17th to the early 19th century. Guidance is offered to engineers who may encounter these when working on an existing building.

有许多原因，可能需要在历史建筑物上更换石头。这些包括年龄相关的腐烂和风化，在材料选择或设置，缺陷的固定和结构失败方面的工艺差。在评估中，主要目的是在实用的情况下保留历史性的面料。然而，替代的决定将在很大程度上取决于清楚地了解石头的重要性，无论是单独的，也是在其所在的内容中，其预测的寿命或耐用性及其成本。

When existing buildings need to be inspected and assessed, the structural engineer is often presented with the challenge of needing X-ray eyes. Lacking such a gift, and despite what clients may assume, the engineer draws instead on knowledge and experience to make value judgements in many situations, with appropriate margins of safety and consideration of appropriate risk incorporated along the way. Codes of practice and British Standards are not to be ignored, but are a useful tool to assist with this process. This article aims to discuss some of the issues, challenges, tools and techniques available to the practising structural engineer when assessing existing structures. While the article focuses principally on floor structures, the techniques can be used on a range of applications to provide an understanding of how existing structures are actually behaving, rather than how we might think they are working.