古建筑木构件材料主要力学性能检测方法研究

为在不损害木构件功能情况下,于现场快速、有效地检测评估出构件材料的主要力学性能,以北京圆明园正觉寺鼓楼拆卸下来的落叶松材为试验对象,对力学试件进行应力波传播速度、微钻阻力、密度等检测,力图以微钻阻力与应力波速度平方的乘积（应力波-阻力模量）作为评估木构件材料力学性能的指标。经过与传统力学性能检测方法的检测结果对比发现：...

Determining main mechanical properties of ancient architectural timber

During maintenance of ancient wood architectures, it is critical to non-destructively and effectively determine the residual mechanical properties of key wood structural members, so that degraded members may be replaced or repaired to avoid structural failure. Experimental materials used in this study were larch (Larix principis-rupprechtii) timber samples taken from the drum-tower of Zhengjue Temple of Yuanmingyuan (Old Summer Palace) in Beijing. The timber samples were cut into standard specimens first, and then stress wave measurements, micro-drilling tests and density tests were conducted. Product of resitograph and stress wave speed squared is defined as modulus of stress-resistograph in this study. We conducted static bending and compression parallel to grain tests on the standard specimens to determine the modulus of elasticity, bending strength and compression strength. Our analysis indicated that the modulus of stress-resistograph had good linear regression relationships with modulus of elasticity (MOE), modulus of rupture (MOR) as well as compression strength, and the coefficients of determination were 0.505 6, 0.260 9 and 0.477 3 respectively. In order to better evaluate the main residual mechanical properties with parameter of the modulus of stress-resistograph, 95% confidence regression equations are suggested to be used in real situation.