Dynamic Barriers
2020
BETWEEN GREYMOUTH AND WEST PORT - WEST COAST - New Zealand
NZ Transport Agency (NZTA)
SH6 MEYBILLE BAY
Problem
State Highway 6 (SH6) is the shortest route linking Greymouth town and West Port town and runs parallel to the coastline. Its scenic view attracts many international tourist to use this route. Meybille Bay is located along SH6 in the Punaikaki Coast. NZTA appointed Opus International Consultant Ltd to identify hazardous rockfall sites along the SH network in the South Island region. Under the current hazards rating system, Meybille Bay was identified as a high risk area thus in need for immediate rockfall protection solution.
Solution
After identifying the most probable boulder size and rigorous detail rockfall trajectory analysis, Opus has ascertained the most suitable rockfall protection structure (RPS) to be a Hybrid Fence with an energy rating of 3,000kJ. Unlike standard rockfall dynamic barriers; Hybrid Fence does not stop the falling rocks but dissipates the rock kinetic energy by intercepting them in the suspended panel across the posts; and guides the rocks down to the toe of the drape to be disposed later. Maccaferri assisted with the preparation of the layout drawings for the engineer’s approval and supplied the fence kit system for this project. During the installation stage, Maccaferri provided onsite assistance by participating in regular site visits, providing installation guidance and preparation of relevant shop drawings for the contractor. The contractor performed the installation with a 3-man team and took approximately 4 weeks to complete.