Lightweight Beaching Ramp for Ships

Objective: Develop a durable, lightweight, corrosion-resistant beach ramp for newly constructed Medium Landing Ships (LSMs). Description: The Medium Landing Ship (LSM) is a new construction beachable vessel intended to perform ship-to-shore amphibious movement of cargo, equipment, and troops. To accomplish the loading and unloading of equipment, a large vehicle ramp is needed for Roll-On/Roll-Off (RO-RO) capability. Large RO-RO ramps are used on multiple ship classes and are commonly made of heavy steel, susceptible to corrosion and maintenance issues. On beaching vessels, these ramps are constantly subjected to saltwater immersion and are expected to traverse a long distance to provide a safe transfer of vehicles to the shore. Without a properly functioning ramp, the primary mission of these beaching vessels is compromised. There is currently no commercial technology that can meet this need. The Navy seeks a reliable, low maintenance, corrosion resistant ramp system for beaching vessels. The legacy ramps are mostly made of steel and are often submerged in seawater while rolling stock compromises paint protection causing corrosion. Due to complex geometric challenges of beaching a large vessel, complex articulating beaching ramps tend to be very long and heavy (typically about 75’ and 110 tons). These length and weight challenges of deployment systems tend to be unreliable and often have mission degrading failures. The solution should be at least 13 ft in width and 75 ft in length and support a maximum vehicle load of 70 tons (tire contact load of 32,100 lbs. over 24” x 25.5” patch area). The ramp should be articulated from a single hinge point using hydraulics on the ship. However, the solution can be divided into as many subsections as necessary such as employing the use of multiple folds to accommodate the length and weight requirements. The time it takes to deploy the ramp, however, shall not exceed 30 minutes. The technology should utilize maintainable systems for deployment and retraction. The developed solution should reduce maintenance requirements while maximizing reliability of the deployment/retraction system. The durability of corrosion resistant material should last the life cycle of the ship (30 years). The solution should take extreme environmental conditions such as wind, humidity, and sea spray into consideration as such conditions can decrease the life cycle of a technology. The solution should have a nonskid surface that is able to withstand the demands of high traffic during loading and offloading of heavy equipment and vehicles. Keywords: Medium Landing Ship (LSM); lightweight Ramp; Lightweight ferry ramps; Advanced Materials; Corrosion resistance; Roll-On/Roll-Off (RO-RO) ramps CMMC Level: Level 2 (Self)