CLT construction performance under thermal loading

The paper deals with testing fire resistance of a vertical wooden building construction made of CLT panels subjected to the medium-scale test of the fire resistance. A model test of fire resistance with the ceramic radiation panel as the radiation heat source, with achievable temperature of radiation surface of 935°C at maximum was used. The aim of the experiment was to assess the experiment sample whether it meets the request of the thermal insulation and integrity under thermal loading of the model fire for 30 min. The test resulted in the increase of temperatures on observed thermocouples and assessment of the integrity on the unexposed side of the CLT panel. The construction clearly resisted the effects of the radiation heat during 30 min and maintained the observed criteria of fire resistance. Charred layer of the CLT panel created on the surface of the exposed side in the thickness of 20 mm inhibited the heat transfer into the further layers of construction.