Sulfate Attack on Concrete - Chapter 1

Portland clinker dựa trên bê tông là vật liệu xây dựng quan trọng nhất và linh hoạt được sử dụng. Nó là một vật liệu composite vô cùng phức tạp, và xem xét hóa học của nó, vật lý, và lộn xộn microstructural, nó cũng là một loại vật liệu rất tha thứ: mặc dù lạm dụng nghiêm trọng bởi con người và thiên nhiên, hầu hết số tiền to lớn của bê tông clinker dựa trên Portland sử dụng thế giới hơn là thực hiện chức năng của nó dự định đáng ngạc nhiên. . | 1 Introduction Portland clinker-based concrete is the most important and versatile construction material used. It is an extremely complex composite material and considering its chemical physical and microstructural intricacy it is also a very forgiving material in spite of severe abuse by Man and Nature most of the immense amounts of Portland clinker-based concrete used World over are performing its intended functions surprisingly well. However this generally good performance of concrete is not a satisfactory excuse for improper or inadequate utilization by Man of the available knowledge generated during the past 100 or more years. To the contrary the cost of repair of deteriorated concrete and its possible replacement not speaking about the societal cost of expensive litigations and other unnecessary expenses more than justifies investment into better understanding of the nature of concrete and its performance in the environment it is used. This book is meant to be a humble contribution to dissemination of available information about basic aspects of concrete material science and more specifically about proper treatment of both fresh and hardened concrete to assure long-lasting durability of concrete structures in sulfate-bearing environment. Man abuses concrete by use of wrong or marginal concrete materials and improper mix proportions inappropriate use of concrete mix compositions in structures exposed to harsh environment and structural design unsuitable for the given environmental exposure curing or heat treatment in conflict with chemistry and physics of concrete microstructure development wrong placement and finishing procedures and lack of maintenance. 2002 Jan Skalny Jacques Marchand and Ivan Odler Nature causes additional challenges. Of these the most important examples are environmental conditions extreme temperatures temperature and humidity fluctuations access to concrete of chemical species capable of reacting with concrete components atmospheric .