Martin Marietta Texas Quarry Highwall Stabilization
Baltimore
Best Specialized Construction
Presented by: International Geostabilization
Region: ENR Mid-Atlantic
Owner: Martin Marietta Materials
Leading design company | General contractor: International Geostabilization
Support for the structural linkage plan: CW services
Stabilizing a quarry where rock falls threatened to crush critical infrastructure under construction required a meticulous approach and required workers to abseil down slopes to remove loose material. Costing less than $500,000, the design-build project involved stabilization of the outside corner of the high wall for a primary crushing station, mitigating rockfall along the conveyor belt near the wall high and the installation of six micropile caps to structurally support the cover of the dumping ramp.
At the corner of the high wall, a bench collapse caused major slab failure and smaller block failures. A combination of the jointing of the rock mass and the rippling effect of the heavy joint structures created poor conditions that required the team to use rock bolts and a reinforced layer of shotcrete to reinforce the area. In the second area, where rock falls had occurred over the past year on a 900-foot slope near the future conveyor belt, crews used ladder techniques to remove loose debris and install rock anchors for additional support, a particular challenge given the work in the upper ridge area. was limited The teams successfully coordinated to stay safe.
Constructing a technically complex retaining wall with a half-hill base on budget and on schedule in two months with zero lost time incidents and no OSHA recordable accidents impressed the judges. “The safety record was perfect for something that could go wrong in safety,” noted one judge. “That’s where the risk is.”
Jeff Segar, chief geostructural engineer at GeoStabilization International, says his company’s role went beyond the structural design solution for the cantilever roof foundation. “We created interventions that not only improved the success of the project, but preserved a design that could not have been implemented without our expertise and limited access equipment,” he says.
