SMOOTH-WALL TUBING FOR SUPPORTING UNDERGROUND WORKINGS DRIVEN IN PERMAFROST Russian patent published in 1998 - IPC

FIELD: mining industry. SUBSTANCE: this particularly relates to supporting vertical mine shafts driven in permafrost rock by prefabricated reinforced concrete articles. Tubings with their outer walls made of load-bearing stiffening ribs are connected to each other in vertical and horizontal planes by means of built-in fastening members. Inner wall is made in the form of integral guarding shell which creates smooth-wall surface of working. End surfaces of shell wall are connected with peripheral load-bearing ribs of outer wall. Space between load-bearing ribs of outer wall and inner volume embraced in guarding shell are filled with thermal-insulating material. EFFECT: high efficiency. 15 dwg