EXPERIMENTAL VERIFICATION OF THE STRAIN-STRESS DISTRIBUTION OF A HINGED VENTILATED FACE SUBSYSTEM UNDER NONSTATIONARY LOADING

Abstract

Hinged ventilated faces (HVFs) are among the most effective solutions for thermal renovation of buildings in extreme continental climates. A previous study developed a “boundary optimization” methodology for the HVF subsystem topology using the finite-element technique (FET): increasing the bracket spacing from 600 × 600 mm to 1000 × 1000 mm reduces the thermal irregularity coefficient from 8.33% to 3.0% while keeping stresses within 75% of the material’s yield point. However, experimental verification under seismic loading has been lacking, limiting the approach’s direct application in design practice. This study experimentally verifies the finite element model of an HVF subsystem under nonstationary loading, for bracket radiuses of 150 mm and 200 mm at 600 × 600 mm spacing. The novelty lies in the quantitative justification of the FE modeling strategy through direct comparison of calculated and experimental von Mises stresses and displacements, with a physical explanation of their systematic discrepancy. Tests were performed on full-scale (1:1) specimens using a uniaxial electrodynamic vibration bed, with seismic action defined by synthetic accelerograms compatible with design spectra for soil category III at seismicity of 8 and 9 (MSK-64). Deformations were measured with strain gauges and displacements with laser sensors, for four configurations under two seismic directions. The resulting deviation of 12.0-12.6% remained within the ±15% verification threshold, confirming the FE strategy’s adequacy for engineering calculations and providing an experimentally validated basis for extending the “boundary optimization” methodology to larger bracket spacings and other seismically active regions.