Part 1 of 2: A comparison of three methods of non-de- structive testing technology methods on wood structures

摘要

Timber bridges comprise a smaller percentage of the total bridges in the world today as the number of concrete and steel bridges increases. In North America, there are approximately 1 million timber bridges currently in service-both in railway infrastructure and in local government jurisdictions. With a dwindling supply of knowledge and practical experience base in timber bridge inspection and maintenance within the local governments and railways, many now rely on external consultants and contractors who have experience with concrete and steel bridges, but very little experience with timber bridges (particularly old ones). Local governments turn to timber bridge inspection and maintenance standards published by state highway authorities as criteria for timber bridge inspection offerings. These maintenance and inspection manuals are frequently re-issued with very few upgrades to reflect the current state-of-the-art based on worldwide developments. This in turn leads to poor, outdated maintenance practices, further escalating the demise of the timber bridges.