学术报告——Resilience of reinforced concrete structures in corrosive conditions （腐蚀环境下钢筋混凝土的韧性研究）

报告题目：Resilience of reinforced concrete structures in corrosive conditions （腐蚀环境下钢筋混凝土的韧性研究）

报告人：Robert E. Melchers

报告时间：10月21日（星期二）10:00 - 12:00

报告地点：西华大学5A427会议室

主办单位：材料科学与工程学院

报告人简介：

Robert E. Melchers, Professor of Civil Engineering (Emeritus), The University of Newcastle, Australia, BE, MEngSC (Monash), PhD (Cambridge, UK), Fellow, Australian Academy of Technology and Engineering. Honorary Fellow, The Institution of Engineers Australia. Awards include 2009 ACA Corrosion Medal, 2012 Jin S Chung Award (ISOPE), 2013 John Connell Gold Medal (The Institution of Engineers, Australia), 2014 Eminent Speaker, Structural College, The Institution of Engineers, Australia, 2006 and 2018 Guy Bengough Award (IOM3).

Robert E. Melchers，澳大利亚纽卡斯尔大学土木工程学院荣誉教授。先后获莫纳什大学工学学士、工程科学硕士及英国剑桥大学博士学位，澳大利亚技术与工程院院士、澳大利亚工程师协会荣誉会士。曾荣膺2009年度澳大拉西亚腐蚀协会腐蚀奖章、2012年国际海洋与极地工程学会(ISOPE) Jin S. Chung奖、2013年澳大利亚工程师协会的最高奖John Connell Medal、2014年澳大利亚工程师协会结构学院杰出演讲人称号，并于2006年及2018年两度获英国材料、矿物与采矿学会(IOM3) Guy Bengough奖。

报告内容简介：

This presentation reviews why reinforced concrete structures, properly made, can endure very aggressive conditions for very long periods of time without reinforcement corrosion or concrete deterioration. Field evidence for this has been available for many years. Laboratory experiments do not always properly represent the behaviour of actual concrete structures. Chlorides are of little importance early in the exposure period. High quality well-compacted, low-permeability concretes eventually deteriorate through the slow outward leaching of concrete alkalis mainly Ca(OH)₂. Its loss is accelerated when chlorides are present. Also reviewed is recent experience with so-called 'carbonation' of concrete. Usually, this is assumed to cause reinforcement corrosion. It is shown that in this case, too, the critical mechanism is the slow loss of Ca(OH)2 by outward leaching. The calcium carbonate layer (carbonation') on the external surface tends to act as a diffusion barrier for such leaching. In addition to these two mechanisms, increasing evidence suggests that reinforcement corrosion may be the result of alkaline-silicate reactivity (ASR) or alkaline-aggregate reactivity (AAR) of the aggregates in the concrete. These break-down of protection of the concrete through break-down and expansion of aggregates.