Canyon Creek Road Rockslide Mitigation

In 2021, Access Limited investigated a rockslide along Canyon Creek to devise both temporary and permanent protection solutions for the roadway. The exposed rock formations, primarily schist and meta-sedimentary rocks with traces of shale, are highly susceptible to mechanical and chemical weathering due to their hydrothermally altered nature.

The project site, situated along the near-vertical to vertical road cut for Canyon Creek Road, underwent cleanup during the initial rockslide, where large rock blocks buried the excavator. Two areas required mitigation and protection. Priority site 1, with boulders of approximately 8-ft x 10-ft and large open cracks above the slope's brow, spans a 100-ft height and 210 ft road length. Site 2, to the east, posed a potential rockfall area with loose boulders but showed no evidence of slope instability.

Our comprehensive solution involved clearing and grubbing, safety manual and mechanical scaling, and the installation of a moveable rockfall barrier. Additionally, we employed up to 50 (each) 50-foot tieback anchors, up to 500 (each) 9-foot mesh anchors, and up to 40,000 SF of Geobrugg spider mesh.

Rockfall Barrier Solutions

Rockfall barriers, crucial for reducing the risk of rockslides and debris impacting infrastructure, are typically made of steel cables or mesh anchored to the ground. They absorb falling rock energy and distribute it evenly along their length.

What materials compose rockfall barriers?

Rockfall barriers incorporate carefully chosen materials for strength, durability, and effective containment of falling rocks. The specific materials vary based on the barrier type and project requirements. Common materials include:

1. Steel

• Structural components such as cables, posts, and frames are often made of steel.
• Offers excellent strength and durability, capable of withstanding falling rock impacts.

2. High-tensile Wire Mesh

• Crucial for rockfall barriers, made from woven or welded steel wire.
• Designed to absorb and retain falling rocks, preventing damage to infrastructure.
• High-tensile strength ensures resilience against rockfall forces.

3. Dynamic Energy Absorbers

• Devices integrated into barrier systems to absorb and dissipate energy from falling rocks.
• Typically made from materials like steel or aluminum.
• Deform or compress under high impact loads, reducing force on the barrier and minimizing damage risk.

4. Geotextiles

• Synthetic materials like polyester or polypropylene are used for additional reinforcement.
• Placed behind rockfall mesh to prevent erosion and enhance overall barrier performance.

The Access Limited Rockslide Mitigation Approach

Our team utilized a range of skills, from scaling and crane-suspended rockfall barriers to excavation and rock-bolting. We offer flexible, customized solutions for emergency rockslide management, with the ability to adjust plans mid-project to prioritize public safety and mobility.