Experimental study of cross-laminated timber wall panels

The use of cross-laminated structural timber elements is becoming increasingly popular. The number of layers varies normally from three upwards. The structural performance of five-layer cross-laminated timber elements was investigated. The five layers consisted of 19 mm thick boards, laid successively at right angles to each other and glued together with PU-adhesive, layers 1, 3 and 5 lying in one direction and layers 2 and 4 in the other. The stiffness and strength of four cross-laminated timber elements (4955 mm long, 1250 mm wide and 96 mm thick) were studied during in-plane bending. Two of the elements were first partitioned into two parts that were reconnected in two different ways prior to testing. The influence of the way in which the cross-laminated timber elements were reconnected was studied, the behaviour observed being compared with the test results for the unpartitioned specimens with respect to both strength and stiffness. The experimental tests performed showed the cross-laminated timber elements to possess a high degree of stiffness and strength. There was also found to be a marked difference in behaviour between the two different ways in which the elements were connected to each other. One of the two connecting methods studied, being of less good design but earlier frequently used in Sweden, showed as expected poor structural performance, whereas the other one applied as a safer alternative performed well.