| 残损斗栱节点受力性能试验研究 |
| |
| 引用本文： | 陈九璋,陈雪瑶,戴璐.残损斗栱节点受力性能试验研究[J].北京林业大学学报,2020,42(2):149-158. |
| |
| 作者姓名： | 陈九璋 陈雪瑶 戴璐 |
| |
| 作者单位： | 北京林业大学材料科学与技术学院，北京 100083 |
| |
| 基金项目： | 中央高校基本科研业务专项资金资助（BLX201719），北京林业大学大学生创新训练项目（X201810022106） |
| |
| 摘 要： | 目的斗栱是古建筑木结构的重要组成部分，对维持整体结构力学性能的稳定起着至关重要的作用。现存古建结构中的斗栱节点都存在着一定的残损变形，而目前对斗栱节点力学性能的研究多以完好的斗栱为试验对象，甚少考虑残损状态，尤其腐朽、虫蛀带来的体积损失对斗栱节点力学性能的影响。因此，研究残损对斗栱节点乃至整体结构力学性能的影响具有十分重要的现实意义，可为古建木结构的修缮与保护提供科学依据。方法以应县木塔二层平坐层的典型柱头铺作为研究对象，以1∶3.5的缩尺比制作了4组斗栱节点模型，保持1组模型完好，对余下3组进行不同位置钻孔的人工残损处理来削弱斗栱组成构件的受力截面，从而模拟斗栱的残损. 通过进行竖向加载试验，得到了4组斗栱节点的荷载?位移曲线，结合试验现象明确了残损斗栱节点的受力和变形特征。结果竖向荷载作用下，斗栱节点的破坏主要体现在第二跳华栱的断裂、弯曲变形和交互斗的开裂。残损斗栱节点的破坏形态与完好斗栱节点相似，但破坏程度更严重。其极限荷载与抗压刚度都有所下降，且残损对斗栱节点的抗压刚度影响更为显著。结论在残损类型相同，且结构整体残损度相近时，第一跳栱的残损对斗栱节点极限荷载和抗压刚度的影响最大。
|
| 关 键 词： | 古建筑木结构 斗栱 残损 竖向加载 荷载?位移曲线 |
| 收稿时间： | 2019-07-03 |
Experimental research on mechanical performance of damaged bracket set joints |
| |
| Institution: | School of Materials Science and Technology, Beijing Forestry University, Beijing 100083, China |
| |
| Abstract: | ObjectiveThe bracket set is an important component of the wooden structure in Chinese ancient architecture system, which plays a vital role in maintaining the mechanical properties of the whole structure reliable. There are different degrees of damage of bracket set joints in existing ancient structures. While at present, most of the researches on the mechanical properties of bracket set joints are based on intact bracket sets, and little consideration is given to the mechanical properties and deformation rule of damaged bracket sets, especially under the condition of decaying and volume loss caused by worm moths. Therefore, it is of great practical significance to study the effect of damage on the mechanical properties of bracket set joints or even the whole structure, which can also help provide scientific basis for the repair and protection of ancient timber structures.MethodThis research took a typical second-story bucket arch on columns in supporting platform of Yingxian Wooden Tower, Shanxi Province of the northern China as the object, and made four groups of bracket set models with the 1/3.5 scale. One group of model kept in perfect condition, while the remaining three groups were drilled with holes in different positions artificially to weaken the stress-bearing section of components of the bracket set joints, so as to simulate the real damage to them. By adopting the vertical loading test, the load-displacement curves of four groups of bracket set joints were obtained, and the mechanical characteristics and deformation performances of bracket set joints were clarified combining the test result.ResultThe test result and data analysis showed that under certain vertical loads, the failure of bracket joints was mainly reflected in the fracture, bending deformation of the second-story Hua-Gong and cracks on the connection block. The failure mode of damaged bracket set joints was similar to that of the intact one. While pre-drilled groups sufferred from worse damage as their ultimate load and stiffness decreased, and the negative effect caused by the former damage was more obvious on the stiffness of bracket set joints.ConclusionWhen the damage type is the same and the overall damage condition of the structure is similar, the damage on the first story of a bracket set joint would exert greater influence on stiffness, which means it is easier to deform when bearing vertical loads. |
| |
| Keywords: | |
|
| 点击此处可从《北京林业大学学报》浏览原始摘要信息 |
| 点击此处可从《北京林业大学学报》下载免费的PDF全文 |
|
