CIB-W18 Timber Structures – A review of meeting 1-43 2 MATERIAL ...
CIB-W18 Timber Structures – A review of meeting 1-43 2 MATERIAL ...
CIB-W18 Timber Structures – A review of meeting 1-43 2 MATERIAL ...
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the laminations were determined and classified according to CEN draft<br />
standards <strong>of</strong> that time (C30-12E and C37-14E). Glued laminated test<br />
beams following different strength classes (LH 35, LH40 and LC38) were<br />
constructed and tested in strength and stiffness.<br />
At the same time strength and stiffness values <strong>of</strong> these beams were calculated<br />
independently by means <strong>of</strong> the Karlsruhe calculation model. Information<br />
about the properties <strong>of</strong> the laminations i.e. the statistical distribution<br />
<strong>of</strong> density and modulus <strong>of</strong> elasticity <strong>of</strong> the boards used for the three<br />
different combinations, about the finger-joints, and about the built-up <strong>of</strong><br />
the beams were known from the Norwegian pre-tests. The results <strong>of</strong> the<br />
beam tests were kept secret until the predictive calculations were available.<br />
The strength <strong>of</strong> all beam combinations (mean value and 5-percentile)<br />
were proved to be in very good agreement with the calculated values<br />
(within 4 % deviation). By this study it became once more evident that the<br />
Karlsruhe calculation model is suitable to predict the strength <strong>of</strong> glued<br />
laminated beams. It is on that account an appropriate aid for the evaluation<br />
<strong>of</strong> standards on strength classes for glulam based on the relevant properties<br />
assigned to the laminations and the finger-joints.<br />
Fig. 1 Beam combinations tested.<br />
Fig. 2 Beam test configuration.<br />
26-12-2 R Hernandez, R H Falk<br />
Simulation analysis <strong>of</strong> Norwegian spruce glued-laminated timber<br />
Abstract<br />
A computer analysis model, referred to as PROLAM, was used to simulate<br />
the performance <strong>of</strong> glued-laminated (glulam) timber beams manufactured<br />
from Norwegian spruce lumber. Mechanical properties <strong>of</strong> tested lumber<br />
and finger joints were analyzed to determine the input properties required<br />
by the model, and Monte Carlo simulation procedures were used to compile<br />
and characterize bending strength and stiffness distributions <strong>of</strong> the<br />
glulam beams. Simulated glulam beam results compared reasonably well<br />
with actual results. Sensitivity analyses were also conducted to observe<br />
both the effects <strong>of</strong> redistribution <strong>of</strong> stresses within a glulam beam, and the<br />
influence <strong>of</strong> finger-joint tensile strength on glulam beam bending strength.<br />
Conclusion<br />
In summary, the lumber and finger-joint data from Falk et al. (1992) were<br />
analyzed to develop input properties required by a glulam beam simulation<br />
model developed by Hernandez et al. (1991). When the input lamination<br />
property values were used to simulate glulam beam performance, simulated<br />
results compared well with the test results.<br />
Sensitivity analyses indicated that when the tensile strength <strong>of</strong> all the<br />
laminations were held constant and only the core laminations were reduced<br />
in stiffness, the decrease in bending strength was less than 4 percent.<br />
However, when the same stiffness configurations were modeled<br />
while considering the reduction in lamination tensile strength correspond-<br />
<strong>CIB</strong>-<strong>W18</strong> <strong>Timber</strong> <strong>Structures</strong> <strong>–</strong> A <strong>review</strong> <strong>of</strong> <strong>meeting</strong> 1-<strong>43</strong> 2 <strong>MATERIAL</strong> PROPERTIES page 2.37