WOOD RESEARCH Volume 70, Number 1, 2025
Vladimír Mózer, LUKÁŠ VELEBIL, and ANDREA SMETANOVÁ

INVESTIGATION OF CLT PANEL DEGRADATION DURING HEATING AND COOLING PHASES OF FIRE

The research presented in this paper investigates the behavior of Cross-laminated timber (CLT) under fire exposure during the heating and cooling phases. A sample CLT panel was exposed to a 60 min heating phase as per the ISO 834 standard time-temperature curve, following which it was removed from the furnace and left to cool at ambient temperature. Due to char formation and availability of oxygen during the intended cooling phase, the intensity glowing combustion was growing and resulted in increasing temperatures and even flaming combustion in its latter stages. The char layer thickness doubled during the intended cooling phase under the experimental conditions. Temperature profiles measured parallel and perpendicular to isotherms indicated significant underestimations associated with the perpendicular orientation. The study highlights the need for consideration and further investigation of the cooling phase and its impact on structural design and fire investigation

WOOD RESEARCH Volume 65, Number 5, 2020
LUKÁŠ VELEBIL and Petr Kuklík

Strength and stiffness of mechanically jointed CLT panels loaded by shear in plane

This article is focused on research into the racking strength and stiffness of mechanically jointed cross laminated timber shear walls considering the influence of fasteners between the layers of boards on the stiffness of panels. The work includes an experimental analysis and analytical model. The experimental analysis included tests of the shear wall panels, tests of the specimens to determine the stiffness at the joint of the layers and material tests. The analytical model based on the component method allows the determination of the racking strength and horizontal displacement of the shear wall in dependence on the number of layers and the number of fasteners in the joint of layers, parameters of the anchorage to the substructure and applied external load. The outputs of the numerical model and the results of the experiments agree relatively well. The largest relative displacement error is 18%.