Design Challenges associated with the use of Non-Metallic Materials in Marine Sheet Pile Walls.

With long term durability, low maintenance and long design life as the standard requirements for high-value marine infrastructure projects, designers are increasingly looking for innovative ways to meet these engineering and economic challenges. One particular example is sheet pile walls, for which replacement during a structure’s life is often either impossible or not practicable. 

Sheet pile walls are often subject to aggressive environments. Exposed to a combination of submerged, tidal, atmospheric and buried environments, they can also be subject to impact and abrasion during service. The traditional approach to steel sheet pile wall durability has been through the use of secondary corrosion protection measures such as protective coatings, cathodic protection systems or corrosion loss allowances. While generally effective in the submerged zone, neither of the first two options are very effective above water especially in the long term. Furthermore these systems can require extensive ongoing monitoring and maintenance. 

This paper identifies and reviews a number of alternative non-metallic sheet pile materials and products which are available in the market. While the durability and structural design risks associated with traditional metallic sheet piles are well known and a standardised design approach exists, these unfamiliar materials come with their own risks and limitations. The authors identify and discuss design challenges including potential durability risks to be considered when designing with these specific material types, as well as the impact of different material properties (both long and short term) on structural design.