Design and Constructability Optimization in the Repair and Restoration of 60-Year-Old Rubble-Mound Jetties: A Case Study of the Aransas Pass Jetties in Texas

Redesign and repair of severely deteriorated rubble-mound jetties to their original stable configuration poses unique challenges. This paper describes the structural design and constructability optimization that were conducted to minimize construction delays and cost overruns in the redesign and restoration of the 60-year-old Aransas Pass jetties in Texas. A visual analysis of satellite imagery, site visit photographs, and hydrographic and light detection and ranging (LiDAR) surveys enabled key observations regarding the condition of the jetties. Empirical analyses of ship-induced waves and numerical modeling of storm waves were performed to establish design parameters for the hydraulic loading and blocks of the jetty head, trunk, and toe sections. A wide range of empirical design formulas were evaluated to instill confidence in the sizing of the slope armor and toe blocks of the jetties. Designing a stable toe configuration proved to be particularly challenging because of a significant disintegration of the original toe structure due to scour and the wide variation in seabed elevations along the length of the jetties. Significant cost and construction savings were obtained by optimizing the slopes of both jetties to a slope steeper than the original design for the trunk sections of both jetties. Static geotechnical stability was assessed for both jetties and was found to be satisfactory. The lessons learned during the redesign, optimization, and constructability assessment can be applied to the repair and restoration of similar rubble-mound jetties.