重组竹高温处理后的性能研究

Performance of Glued Laminated Bamboo after High Temperature Treatment

为了研究重组竹在高温后的性能特点,将重组竹试样置于100~300℃下处理2h,自然降温至室温后,对其质量损失率、裂纹宽度、顺纹抗压强度及破坏形式进行测试和分析。结果表明,随着温度的增加,重组竹的质量损失率逐渐增大,当温度达到250℃,试样出现部分炭化,在300℃质量损失率快速递增到18.6%。在200℃以下裂缝出现较少,最大裂缝宽度只有0.18mm,从250℃开始裂缝增多,在300℃时最大裂缝宽度达到0.52mm。随着处理温度的增加,重组竹的抗压强度有所下降,在300℃时,其顺纹抗压强度仍有62.58 MPa,但极限承载力下降较多,最低的只有508.46kN,说明重组竹在高温后还具有较大的抗压强度,不会大幅降低建筑物的安全性能。

In order to understand the characteristics of the bamboo timber after high temperature treatment, the bamboo samples were exposed to high temperature from 100℃ to 300℃ for 2 hours,after cooled to room temperature,the mass loss rate,crack width,compressive strength and failure mode were analyzed. The test results showed that the mass loss rate of the glued laminated bamboo gradually increased with the increase of temperature. At 250℃, the samples appeared partial carbonization and the mass loss rate in creased to 18.6% at 300℃. Below 200℃, less cracks occurred, the maximum crack width was only 0.18 mm. From 250℃ to 300℃ ,the number of cracks increased and the maximum crack width was 0.52 mm at 300℃. The compressive strength of glued laminated bamboo decreased from 100℃ to 300℃. The compressive strength was 62.58 MPa at 300℃ ,but the minimum ultimate bearing capacity was only 508.46 kN. The results indicated that glued laminated bamboo had a great compressive strength after high temperature treatment,and it would not significantly reduce the safety performance of the building.