Salt-Water Aging, Bonding, and In-Service Performance of a Novel Poured Silicone Expansion Joint Sealant for Small Movement Bridges

Salt-Water Aging, Bonding, and In-Service Performance of a Novel Poured Silicone Expansion Joint Sealant for Small Movement Bridges
Author: Dominic Kruszewski
Publisher:
Total Pages:
Release: 2016
Genre: Electronic dissertations
ISBN:

According to ASCE’s 2013 Infrastructure Report Card, over 200 million trips are taken daily over a structurally deficient bridge in the United States. One of the most commonly observed degradation factors that contribute to compromising the structural integrity of bridges includes leaking expansion joints which allow water, debris and deicing corrosive materials to penetrate through to the substructure. These corrosive agents can significantly damage the bearing and other key components of the bridge, hindering the lifespan of the structure. Currently, poured silicone sealant joint systems must be replaced every 2-3 years in Connecticut. A novel silicone foam sealant has been developed to provide a long term, cost effective sealing method for small movement expansion joints. The foam sealant, developed by chemically modifying the commercially available silicone sealant developed by Watson Bowman Acme Corp. (termed â€solid sealant†herein), expands approximately 70% of its initial volume allowing for significant material savings compared to the existing product. Furthermore, the stress modulus of the foam sealant was observed to be significantly lower than that of the solid sealant, yielding reduced stresses at the interaction surface between the sealant and the substrate. This research work presents the laboratory experiments conducted to compare the bonding properties of the foam and solid sealant, as detachment from the substrate is a major concern. Each experiment contained some combination of variables such as varying substrate materials and primer application. A five-month aging study was performed to observe the adhesion characteristics of both sealants with and without the presence of road salt as a function of accelerated aging. The salt water aging experiment revealed that the application of primer onto the contact surface of the substrate yielded no significant difference in tensile and/or adhesion performance. The solid sealant’s ultimate strain did not improve and the failure mode was almost always characteristically adhesive. Similarly, the ultimate strain of the foam sealant did not significantly change when primer was applied, and the cohesive failure mode was also consistent regardless of primer treatment. Both sealants, however, exhibited a reduced ultimate stress and while the ultimate strain increased as a function of aging. Additionally, through the assistance of the Connecticut Department of Transportation, the foam sealant expansion joint system was installed on three bridges throughout the state to assess its performance under real conditions including environmental and vehicular effects. Both sealants were installed in a systematic manner to allow for direct comparison of their performance under the same conditions. Finally, field monitoring of the expansion joints was performed to understand the movement of each joint gap and determine whether the foam sealant can be considered as an effective sealing system under these demands while also monitoring the performance of the solid sealant. After several site visits, a few cohesive failures were observed in both sealants which were installed on the bridge with the largest joint gap. Two of these failures were located where the solid sealant was installed, while one failure occurred in the foam sealant. All three bridges are still undergoing consistent monitoring and visual inspection.

Handbook of Sealant Technology

Handbook of Sealant Technology
Author: K.L. Mittal
Publisher: CRC Press
Total Pages: 554
Release: 2009-08-26
Genre: Science
ISBN: 1420008633

Sealing is an age-old problem that dates back to our earliest attempts to create a more comfortable living environment. Prehistoric people used natural sealants such as earth, loam, grass, and reeds to protect the interior of their homes against the weather. Today's applications extend to a myriad of uses. The Handbook of Sealant Technology provide

Sealants in Construction

Sealants in Construction
Author: Jerome Klosowski
Publisher: CRC Press
Total Pages: 330
Release: 1988-11-21
Genre: Technology & Engineering
ISBN: 9780824776770

This comprehensive treatment of the subject assesses the performance characteristics needed for application plus the preformance properties of generic sealants. Illustrated with 100 photos as well as diagrams which explain fundamentals and outline methods to insure the use of appropriate procedures.

Sealing Bridge and Pavement Joints

Sealing Bridge and Pavement Joints
Author: National Research Council (U.S.). Transportation Research Board
Publisher: Transportation Research Board National Research
Total Pages: 60
Release: 1984
Genre: Technology & Engineering
ISBN:

Handbook of Adhesives and Sealants in Construction

Handbook of Adhesives and Sealants in Construction
Author: Joseph S. Amstock
Publisher: McGraw-Hill Professional Publishing
Total Pages: 600
Release: 2001
Genre: Technology & Engineering
ISBN:

Expert's A-Z guide to adhesives and sealants The most up-to-date resource of its kind, this book is the last word on this subject for anyone involved in the use, manufacture, and testing of all types of sealants and adhesives for structural and general sealing, bonding, caulking, glazing, and waterproofing of structures. The author, who is one of the world's foremost authorities on this area, provides the newest technical formulas, specific application examples, equipment and other handling and installing aspects for epoxy...acrylic...cyanoacrylates and anerobics...fluorocarbons and hot melts...asphaltic, oleoresinous and oil base putty...grouts and mortars...butyl sealants...hybrid materials...hypalon, neoprene and nitrile sealants...polysulfide...polyurethane...silicone...and permopol. You'll also find comprehensive data on: firestops and firewall application; insulating glass; waterstops; preformed gaskets; foamed and solid tape; performance, repair, and maintenance of sealants; joint movement detail, design, and schematics; specification, testing and quality assurance; more!