The Finite Element Analysis on Short-Time Flexural Behavior of Glue-Lumber String Beam

ABAQUS finite element analysis was used in this paper to simulate the prestressed glulam string beams. The influence of the number of prestressed steel bar and the prestressing value to short-time flexural behavior of prestressed glue-lumber string beams has been studied. Under the same bearing capacity, the economy of prestressed beams and ordinary beams has been contrastively analyzed. The reason of the difference between the simulation results from finite element and the experimental results was illustrated. The results showed that: when the prestressing value remains unchanged, compared with prestressed beams with 2 prestressed steel bars, the ultimate bearing capacity of prestressed beams with 4 ischolar_main prestressed steel bars increased 19.6∼20.6%, and the ultimate bearing capacity of prestressed beams with 6 ischolar_main prestressed steel bars increased 33.8∼34.7%. When prestressed beams have the same number of prestressed steel bar, compared with prestressed beams with 0 kN prestressing value, the ultimate bearing capacity of prestressed beams with 3.077 kN prestressing value increased 2.6∼38.3%, the ultimate bearing capacity of prestressed beams with 6.154 kN prestressing value increased 5.3∼41.4%, and the ultimate bearing capacity of prestressed beams with 9.232 kN prestressing value increased 7.9∼44.5%. Compared with ordinary glue-lumber beams, prestressed glue-lumber string beam with the same prestressing value can save wood about 64.63%∼70.58%, and reduce the cost of 6.31%∼63.66%. From comparison between analyzing test and the finite element analysis showed that material defect and loss of prestress of glue-lumber would make the stiffness and inverted arch different.