Ground control
Ground freezing method and apparatus
Grout pack restraining system
Grouting compositions
Guide rope stabilizer
Headboard
High-load underground dam
High-strength anchor system, safe room bulkhead, and method...
Hinged base for shoring strut for use in construction and...
Hollow bars and method of manufacture
Hollow fiber glass roof bolt
Hollow rock bolt, self -drilling rock bolt and method of...
Hook plow apparatus for longwall mining
Horizontal earth boring machine
Hydraulic excavator driven by more than one type of energy
Hydraulic prop having a filling valve and a clearing valve...
Ice crib
Improved cable bolt
Improved cable bolt
Improved earth anchor