Author: Howard NewlonPublisher:
ISBN:
Category : Bridges
Languages : en
Pages : 134
Book Description
Among Virginia's research efforts during the 1960's was the study of concrete placed in 17 randomly selected bridge decks during and subsequent to their construction in 1963, with the purpose of relating the properties of the concrete as placed to its subsequent performance. The project reported here examined these.decks and concrete samples removed from them after 14 years of service, again to relate performance to properties and, based upon this relationship, to suggest initial levels of concrete properties required for good performance, particularly where concrete as placed does not comply with specific requirements. Despite the relatively small number of decks and samples, as viewed in comparison to the variables involved, significant relationships among concrete properties and performance are evident from the data, in that resistance to scaling and chloride penetration has been maintained for 14 years by concrete that met the requirements established by American Concrete Institute Committee 201 on Durability. The importance of long established principles for producing durable concrete i.e., low water-cement ratio, consolidation, curing, and cover depths thus have been reconfirmed. A procedure for evaluating the potential durability of concrete using petrographic examinations combined with estimates of service and environmental conditions was developed, and the preliminary application of this procedure to the decks included in this study were encouraging.
