开孔单板层积材破坏模式分析及胶合板强化法

Failure mechanism analysis of laminated veneer lumber( LVL) joists with holes and plywood reinforcement methods

对单板层积材(LVL)搁栅进行三点弯曲试验,分析并对比开孔搁栅及未开孔搁栅的破坏模式,研究在孔洞周围使用钉接胶合板进行强化的方法,评估钉接胶合板的强化效果。结果表明:开孔严重影响搁栅的力学性能,且随着孔径的增大,承载能力减幅明显;在孔洞周围使用钉接胶合板强化法,提高了搁栅的承载能力;增加胶合板厚度和钉子数量,搁栅的承载性能整体呈上升趋势;胶合板对开孔搁栅的强化能力取决于两者间的有效贴合程度。

Three point bending tests were conducted on laminated veneer lumber （LVL） joists. The failure mechanism of LVL joists with holes was analyzed and contrasted with the LVL joists without holes. Reinforcement methods with nailed-plywood around holes were studied, and the reinforced effectiveness of nailed plywood was evaluated. Results showed that joists with a hole have a dramatically reduce in carrying capacity. The plywood worked effectively for reinforcing LVL joists. Experiments also showed that the carrying capacity increasing with increase in the thickness of plywood and the quantity of nails.