Kimley-Horn and Associates, Inc. retained Cornerstone Earth Group, Inc. to provide environmental and geotechnical engineering services at the Monterey Regional Airport for the Runway Safety Area (RSA) Project. Kimley-Horn and Associates, Inc. is one of the nation’s leading planning, engineering, and design consulting firms with over 2,800 staff members in more than 75 offices across the United States, offering full services in a wide range of disciplines including design services for airports. Kimley-Horn and Associates, Inc. and Cornerstone worked closely together to meet the competing needs of aging infrastructure and space demands while making improvements without impacting airport operation activities and airline schedules.
Cornerstone provided cost-effective geotechnical engineering solutions for the runway safety area and access road based on their individual design requirements and variable subsurface conditions. Monterey Regional Airport is located north of Salinas Highway (Highway 68) in Monterey, California. This project consisted of three main components: 1) re-configuring the RSA at the eastern end of the airport site to meet FAA grading criteria for the RSA, 2) constructing a new maintenance road around the east end of the RSA, connecting the south and north sides of the airport on the north side of the runway, and 3) re-configuring the west end of the airport to meet FAA grading criteria for the RSA and constructing the maintenance road. To meet FAA grading criteria for the RSA on the east side required construction of a tiered retaining wall system on its south side to support the fill needed. The tiered wall was up to about 85 feet high. The wall was constructed as a Mechanically Stabilized Earth (MSE) wall restrained by layers of geogrid. The face of the wall was split into 10-foot vertical sections and at 10-foot intervals the wall steps back 10 feet with a 4:1 (horizontal:vertical) slope between wall sections, allowing for planting strips.
Cuts and fills were required to construct the new maintenance road. The cuts into the eastern slope ranged up to about 60 feet. Along the road alignment, the cuts required retaining walls on both sides of the road in some areas. The cuts for the access road were supported by soil nail walls in cut areas and MSE walls in fill areas. As with the wall supporting the fills for the RSA, the face of the soil nail walls were split into about 10-foot vertical sections and at about 10-foot horizontal intervals the wall steps back 10 feet with a 4:1 (horizontal:vertical) slope between wall sections, allowing for planting strips.
As part of the RSA Project, new HMA pavement sections capable of supporting 727 and 757 aircraft were placed in the middle third of the RSA. Appurtenant utilities and pavements were also installed within the access road area.