Behaviour of new and existing concrete structures

老化的基础设施给工程界带来了严重的挑战，特别是考虑到最近北美发生的桥梁坍塌事件。根据现行法规设计的这些结构现在都有不同程度的缺陷。加拿大最大的风险之一是混凝土建筑的倒塌和相关的损失，特别是在地震期间。显然，要实现钢筋混凝土结构更好的可持续性，还需要做更多的工作。这可以做到：1)通过更好的设计来提高结构的性能；2)通过使现有结构的修复和修复更加可行和有效，从而延长其使用寿命。这将有一个额外的好处，即减少对地球的生态危害。

The aging infrastructure presents a serious challenge to the engineering community especially in the light of recent bridge collapses in North America. These structures designed in accordance with the existing codes are now deficient to various degrees. One of the greatest risks in Canada is the collapse of concrete buildings and the associated loss especially during an earthquake. Clearly more work is needed to move towards better sustainability of reinforced concrete structures. This can be accomplished: 1) by better design to improve the performance of structures and 2) by making the rehabilitation and repair of existing structures more feasible and efficient, thereby extending their service life. This will have an added advantage of reducing the ecological harm to the planet.