Articles

Laboratory Development and Characterization of UHPC for the Repair of Navigation Structures

Authors: , , , , , ,

Abstract

Many USACE concrete navigation structures are currently functioning beyond their designed service lives and suffer from damage and deterioration along guide walls and lock chamber wall surfaces. External damage from vessel contact and internal concrete deterioration mechanisms, such as freeze-thaw cycling, often develop a synergetic relationship, compounding the deleterious effects on concrete. Efforts have been made to improve lock wall durability. UHPC is a viable material alternative for lock wall repair and rehabilitation. Its high strength and density contribute to superior resistance to impact and abrasion as well as moisture ingress and transport that drive common concrete deterioration mechanisms. UHPC panels can be made significantly thinner than ordinary concrete panels, will eliminate the need for external steel armoring, and will reduce the amount of required steel reinforcement, thereby simplifying design, installation, and maintenance requirements. Although UHPC typically costs more than normal strength concrete, it is expected that introducing precast UHPC panels as a repair material will ultimately result in long-term cost savings to USACE Districts. An ultra-high-performance concrete (UHPC) using locally sourced materials, referred to as Lock-Tuf, has been designed for use in a precast environment with ambient curing methods and serves as a material proof-of-concept for future lock wall rehabilitations. Mechanical properties such as unconfined compressive strength, flexural response, tensile capacity, impact resistance, and abrasion resistance have been quantified experimentally. Overall, Lock-Tuf performed as well as, or better than, proprietary UHPC in the test methods used in this study while meeting strength and durability requirements for the intended application.

Keywords: UHPC, lock wall, abrasion resistance, impact resistance, local materials

How to Cite: Songer, B. , Scott, D. , Wood, S. , Hackbarth, E. , Mack, T. , Tillotson, A. & Walker, K. (2023) “Laboratory Development and Characterization of UHPC for the Repair of Navigation Structures”, International Interactive Symposium on Ultra-High Performance Concrete. 3(1). doi: https://doi.org/10.21838/uhpc.16636