SEISMIC-PROTECTIVE FOUNDATION FOR STRUCTURES Russian patent published in 1996 - IPC

FIELD: erection of structures in seismic-risky zones on seismic-protective foundations. SUBSTANCE: foundation has stationary slab 1 with spherical recess 2 in its upper part, base 3 of building 4 seated in recess with its lower surface being ball-shaped. Placed between slab 1 and base 3 is filler made as holder with balls 5. Slab 1 consists of two parts movably interconnected by means of vertical hydraulic cylinders which in their turn are connected by pipeline with gas-hydraulic accumulators through parallel-coupled throttle and check valves. Center of spherical recess 2 of slab 1 and ball-shaped surface of base 3 is located above center of gravity of structure by value of:, where I_o - moment of inertia, kg/m²; m - mass of structure, kg. Natural oscillation period of structure relative to center of sphere 2 of slab 1 is determined from relation: , where g - gravity acceleration, m/s². Natural oscillation period does not exceed value of terrain seismic oscillation period. Seismic-protective foundation is provided with set of gas accumulators, its control unit formed as distribution pipeline with valve. It is provided with seismic receiver and sealing ring installed in central part of slab recess. Radii of recess 2 and ball surface of base 3 are different. Surface of slab 1 has wide network of capillary grooves connected to pipelines which make space between slab 1 and base 3 communicating with additional set of gas accumulators. Valves are installed in capillary branching points. EFFECT: high efficiency. 3 cl, 3 dwg