高温中和高温后LVL木纤维复合材的抗弯性能

Bending properties of LVL wood composite at and after exposure to high temperature

为研究LVL木纤维复合材在高温中和高温后的抗弯性能，对104个试样进行了温度在20～225℃下的三点静态抗弯测试。研究结果表明，随着温度的升高，高温中和高温后的抗弯强度、抗弯弹性模量、延性系数均明显减小；相对于高温中的试样，高温后的抗弯强度和抗弯弹性模量均明显较高，而延性系数则较低。根据回归分析，提出了LVL在高温中和高温后的抗弯强度与温度的关系模型，该模型预测结果与实测值吻合良好。

Abstract. Static 3-point bending tests, with a total of 104 specimens, were carried out to study the bending prop- erties of LVL wood composite at and after exposure to high temperature in the range from 20 to 225℃. The test results show that the bending strength （MOR）, modulus of elasticity （MOE） and ductility coefficient （μ） of LVL wood composite at and after exposure to high temperature decrease with the increase of the temperature. However, except for the μ, both the MOR and MOE of LVL wood composite at exposure to high temperature are lower than that after exposure to high temperature. A statistical regression-based model, as a function of thermal exposure temperature, was developed and evaluated for predicted the strength loss of LVL wood com- posite. The predicted theoretical results were consistent with the observed values.