Open AccessThe flexural strength of glue laminated timber beams based on deflection and strain rate with four point bending loading system
Author(s) -
Shyama Maricar,
K Sulendra,
H Listiawaty,
H.O. Baide
Publication year - 2022
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1212/1/012034
Subject(s) - flexural strength , deflection (physics) , materials science , composite material , structural engineering , adhesive , three point flexural test , beam (structure) , urea formaldehyde , neutral axis , bending , layer (electronics) , engineering , physics , optics
The development of utilization of low quality wood as construction material is needed to reduce the exploitation of natural forests. However, low quality wood species have disadvantages in terms of mechanical properties. The mechanical properties of Sengon wood are relatively low, so it does not qualify as a structural element. Therefore, the system glulam can be applied to overcome this problem. The system glulam can produce relatively light structural elements with adequate performance. This system has been extensively developed, even at the stage of applying external reinforcement, to improve the performance of structural laminated beams. On that basis, this study aims to determine the flexural strength of laminated beams of Sengon wood as a low quality wood species. In order to achieve this goal, the laminated beam was tested using method four point bending test method. Tests were carried out on long span laminated beams ( L = 2750 mm) to observe flexural strength. There are five (5) laminated blocks tested, namely (BLS-1, BLS-2, BLS-3, BLS-4 and BLS-5). Each group has dimensions of 55 mm in width and 155 mm in height. Each specimen consists of six layers of wood boards with a density Falcata 0.3 g / cm 3 . The thickness of each layer was 26 mm and bonded with resin urea formaldehyde cold setting. Double-sided adhesive laying of 350 gr / m 2 at a compressive force of 2 MPa. The analysis result shows that the load-deflection relationship between BS-L consists of linear and nonlinear phases. The load performance characteristics of the two types of laminated beams are expressed as the ratio of the proportional limit load to the maximum load. The ratio value is expressed in the form P eBL-s = 0.7 P max BL-S and M eBL-s = 0.7 M max BL-S . This form is similar to previous studies with a P e to P max ratio of 0.80.9. In this case, the average flexural strength of the laminated beam is 17 MPa with a maximum strain of 0.004.