Adhesion of mussel byssus to concrete

Date
2023
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
Structural adhesives offer numerous benefits over traditional mechanical joints in terms of their ability to distribute stresses over a larger surface area, resist corrosion and allow accelerated construction. Despite these benefits, structural adhesives are not commonly used in construction joints due to the poor moisture resistance of commercial adhesives. However, sea animals like mussels have shown the ability to produce adhesives that bond to wet surfaces and maintain established adhesive strength underwater. Inspired by mussel adhesion system (pad and thread), this work aims to advance the knowledge required for developing biomimetic adhesive joints for concrete. We specifically conducted behavioral and mechanical studies (pull-off and peel tests) on mussel byssi deposited on cement paste, carbonated cement paste, and model concrete aggregates (quartz and calcite). ☐ Results from behavioral studies showed that mussels prefer depositing pads on mica and carbonated cement paste (high surface energy substrates). Mussels however have a low preference for teflon (low surface energy substrate) and cement paste (rough surfaces). Pull-off and peel tests results revealed that mussel pads adhere strongly to carbonated cement paste, cement paste and mica as opposed to teflon. The adhesive strength and fracture energy of pads deposited on cement paste (with a 0.45 water-tocement ratio) was 122% and 70% higher than those deposited on teflon, respectively. Furthermore, there was no statistically significant difference between the adhesive strength and fracture energy of pads deposited on carbonated cement paste and cement paste. This evidence suggests that carbonation of concrete may not have detrimental effects on the adhesive strength of adhesives on concrete surfaces. Lastly, peel test, as opposed to pull-off test, gives 100% adhesive failure mode with lower coefficient of variation; hence it is more appropriate for measuring how strongly mussels adhere to a substrate.
Description
Keywords
Mussels, Concrete, Structural adhesives, Cement paste, Distribute stresses
Citation