Document Type : Research Article

Authors

• Sarah Mobley
• Kelly Costello
• Gray Mullins

Department of Civil & Environmental Engineering, University of South Florida, Tampa, FL 33620, USA

Abstract

A common method of constructing foundations for bridges or tall buildings involves deep excavations in which steel reinforcement and fluid concrete are placed while in a submerged state below the ground water table. The excavation stability is achieved by maintaining the fluid level of slurry within the excavation well above the ground water table and thus pushes outward against the soil side walls. The most common slurry products are comprised of clay minerals mixed with water to form a thick consistency capable of suspending soil cuttings. More recently, highly engineered polymer slurry products have emerged that, if used properly, far out-perform the traditional mineral slurry products. This paper outlines test results showing the marked performance improvements. Results from concrete to soil bond, steel reinforcement to concrete bond, and corrosion durability tests are presented from multiple research projects all coming to the same conclusion: present methods that use mineral slurry may be unwittingly constructing poor foundation elements, and polymer slurry alternates result in superior end products.

Keywords

• Bored pile
• drilled shaft
• corrosion durability
• polymer slurry
• rebar bond