Development and Layout of a Protocol for the Field Performance of Concrete Deck and Crack Sealants


Book Description

The main objective of this project was to develop and layout a protocol for the long-term monitoring and assessment of the performance of concrete deck and crack sealants in the field. To accomplish this goal, a total of six bridge decks were chosen for study. The decks have ages that vary from 4 to 30 years old, are all in good condition, though some presented a variety of longitudinal, transverse and diagonal cracking. In each deck, test segments were laid out along one lane in four of the six bridges. Drill powder samples were extracted in each segment in order to determine the in-situ, near-surface chloride ion content of the deck. Laboratory analyses of the samples showed that the chloride ion content varied between 3.2 lb/cy for the younger decks (3 years old) and 20.8 lb/cy for the older decks (28 years old). Based on the recommendations of a previous laboratory investigation, a pool of the best performing deck and crack sealants were selected to be applied in the decks. In two bridges, deck segments were sealed with four deck sealants while one segment was left unsealed to be used as a control segment. Additionally, the cracks in each of these segments were sealed with five crack sealants. While two other decks were also scheduled for sealing as part of this phase of the project, they were not done because the required curing time for some of the products was longer than deemed acceptable by DOT crews for these high traffic bridges. It is recommended, however, that every effort be made to have these decks be sealed in the near future. The remaining two bridges had been sealed at the time of construction. While no specific information could be secured about the product used in these decks, the low chloride ion content in these decks suggested that the applied product has helped reduce the ingress of chloride ions. Therefore, it is recommended that these decks continue to be monitored over time. Based on the inspections and the data collected in the field, a protocol and schedule for the continuing monitoring of sealant performance is presented.




Engineering and Design


Book Description

This manual provides guidance on evaluating the condition of the concrete in a structure, relating the condition of the concrete to the underlying cause or causes of that condition, selecting an appropriate repair material and method for any deficiency found, and using the selected materials and methods to repair or rehabilitate the structure. Guidance is also included on maintenance of concrete and on preparation of concrete investigation reports for repair and rehabilitation projects. Considerations for certain specialized types of rehabilitation projects are also given.



















Structures and Infrastructure Systems


Book Description

Our knowledge to model, design, analyse, maintain, manage and predict the life-cycle performance of infrastructure systems is continually growing. However, the complexity of these systems continues to increase and an integrated approach is necessary to understand the effect of technological, environmental, economic, social, and political interactions on the life-cycle performance of engineering infrastructure. In order to accomplish this, methods have to be developed to systematically analyse structure and infrastructure systems, and models have to be formulated for evaluating and comparing the risks and benefits associated with various alternatives. Civil engineers must maximize the life-cycle benefits of these systems to serve the needs of our society by selecting the best balance of the safety, economy, resilience and sustainability requirements despite imperfect information and knowledge. Within the context of this book, the necessary concepts are introduced and illustrated with applications to civil and marine structures. This book is intended for an audience of researchers and practitioners world‐wide with a background in civil and marine engineering, as well as people working in infrastructure maintenance, management, cost and optimization analysis. The chapters originally published as articles in Structure and Infrastructure Engineering.







AASHTO Guide for Design of Pavement Structures, 1993


Book Description

Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.