METHOD OF FIXATION OF FLOATING-UP TWO-LINE GAS PIPING Russian patent published in 1997 - IPC

FIELD: underground construction; methods of fixation of floating-up pipe lines. SUBSTANCE: trench is formed between lines of gas piping; trenches are also dug on either side of lines; bottom of trench shall not be above bottom of respective line. Then cloths made from water-permeable material are laid over surface formed by walls of trench and upper surfaces of piping lines to avoid penetration of particles of ground and trenches are filled with gravel and crushed rock mixture and ground fill is formed above gas piping. Slopes and upper shelf of ground fill are covered with free ends of clutch and additional fill is formed above them. EFFECT: avoidance of ice halo on outer surface of gas piping excluding its further floating-up. 2 cl, 1 dwg