DEVICE FOR STRENGTHENING OF GROUND BEDS Russian patent published in 1997 - IPC

FIELD: bridge building. SUBSTANCE: permafrost islands are made and preserved for a long period of time in the beds and bridge seats at a temperature below the level of mean temperature of the underlying surface by 5 to 10 deg. C. Non-transparent and waterproof vertical and subvertical laminated screens with an air cavity under them are provided on the boundary of the bridge seat-air system, they are made of glass-reinforced plastic or plastic; one or more air-absorbing ducts are positioned on each screen section on the lower end, and one or more air-escape ducts on the upper end, and vertical screens of glass-reinforced plastic or plastic are made for protection of bridges and surrounding grounds of the approach embankments and bridge seats against the inflow and circulation of river bed and ground waters, side heat flows. With the aim of maximum and continuous turning to account all natural causes and motive forces up to forced circulation of air at railway traffic resulting in the maximum cooling of beds and their seats in average annual and many years plan, the air-absorbing ducts are made of non-transparent glass-reinforced plastics, and the air-escape ducts- of transparent glass-reinforced plastics. Tubular air-entrainments for directing the air streams downwards are made on the air absorbing ducts, and those for directly the air streams upwards are made on the air-escape ducts; besides, the air-escape ducts are furnished with deflectors. To prevent summer circulation of air in the cavity under the screen, and respectively heat exchange of convections and steam transfer, the vertical air-absorbing and air-escape ducts are equipped with automatic swivel devices. EFFECT: reduced operating costs and upset of ecological equilibrium at maintenance, overhaul or reconstruction of bridges of any type, strengthening of beds and seats due to provision of heat shields on bridges of any type without overhauls by mechanical, chemical and other traditional measures and without any use of artificial sources of energy. 4 cl, 4 dwg