某在役古建木结构的模型修正与状态评估

Study on model revision and condition assessment of an existing ancient timber structure

以旧木材材性试验数据和现场静载测试数据为基础,对闽北一在役的古聚落木结构"七家楼"进行仿真力学性能分析.建立"七家楼"准确的整体有限元模型,通过对"七家楼"有限元模型进行正常服役状态下的静力力学性能分析,得到"七家楼"各主要承重构件的应力分布和变形情况,分析穿斗式古建木结构的受力传力体系和薄弱位置,评估结构的安全状态.研究结果表明:以"七家楼"为代表的闽北穿斗式古聚落木民居目前在承载能力和变形能力方面均尚有一定富余;穿斗式木结构中央区域为主要受力区,结构以承重梁架受弯过大为主要失效模型;屋盖梁架体系为结构的薄弱位置,是修缮加固和监控的重点.

Based on the properties of some old wood samples and the in-suit statically loading test result,an accuracy of the whole finite element model of Qijia residential was established by using the finite element model method. Through the statically mechanical property analysis of Qijia residential in the normal service,the strain and deformation distribution of main bearing members could be known.The force transfer system and the structural weak position were also analyzed. Thus the status of Qijia residential was evaluated. The result of analysis above showed that Chuandou timber structures,which were represented by Qijia residential,had a considerable surplus in carrying capacity and deformability. As a whole,top center of structure was the main loading position. The main failure model of Chuandou timber structure was the bending strength destruction. The beam of roof system was the weak position of the structure and was emphases needed reinforcing and monitoring.