FIELD: measurement equipment.
SUBSTANCE: on surfaces of upper and lower beam flanges at a point of maximum deflection Δ0 there bonded are strain gauges with similar characteristics directly onto the prepared surface of the upper and lower beam flanges. Operating and compensating strain gauges are bonded in the number of 3 to 5 pieces in each flange in a section 15 to 25 cm long with maximum deflection Δ0. The operating strain gauges are fixed along primary stresses σ along the beam, and compensating strain gauges are fixed between the operating strain gauges across the beam, protected against different actions with epoxy resin; bridge circuits are mounted for each pair of strain gauges (operating and compensating) and their wires are connected to a strain station; initial resistance R0 of the operating strain gauges is measured; with that, beam deflection Δ(t) at any point of time t is determined by the following formula: Δ(t)=Δ0+r·(|ΔR1(t)|+|ΔR2(t)|), where Δ0 - initial maximum beam deflection at point of time t=0, which is measured by means of a high-precision station rod and a level unit before bonding of the strain gauges; r - constant coefficient depending on design circuits and dimensions of the beam.
EFFECT: higher measurement accuracy.
4 dwg, 1 tbl
