周乾1,2，闫维明1（1 北京工业大学工程抗震与结构诊治北京市重点实验室，北京 100124；2 故宫博物院，北京 100009）

［摘要］采用力学分析方法，研究了古建筑木结构叠合梁与组合梁弯曲受力问题。以工程中常见的矩形木梁为例，讨论了如下3个问题：1) 单梁开裂形成叠合梁后的弯曲受力性能；2) 叠合梁与组合梁弯曲受力性能的区别；3) 古建筑叠合梁“工字形”抗弯截面的合理性。结果表明：1) 单梁开裂后形成叠合梁，将导致截面弯应力峰值大幅度增加；2) 单梁加固采用组合梁做法比叠合梁做法更能节约材料且效果更好，且采用钢材加固木梁比木材加固木梁所需截面尺寸小；3) 古建筑叠合梁“工字形”截面与相应等高度矩形截面相比，受弯承载力变化不大，具有合理性。

［关键词］木结构；叠合梁；组合梁；应力分布；古建筑

中图分类号：TU366-2文献标识码：A文章编号：1002-848X(2012)04-0157-05

Bending analysis on composite beam and combination beam of Chinese ancient wooden buildings

Zhou Qian1,2, Yan Weiming1（1 Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit, Beijing University of Technology, Beijing 100124, China; 2 Palace Museum, Beijing 100009, China）

Abstract:By mechanical analysis methods, internal forces of composite beam and combination beam of Chinese ancient wooden buildings under bending loads were studied. A typical rectangular beam was taken as an example to discuss the following problems: 1) variation of bending stress distribution of the beam after it cracked completely to form a composite beam; 2) when the beam was considered to be strengthened by composite beam or combination beam, the difference of bending performance between them; 3) rationality of “I-section” type of composite beam or combination beam of Chinese ancient buildings.Results show that:1) after a single beam cracks completely to form a composite beam, its peak bending stress value increases greatly,which may make itself destroyed; 2) when a single beam is strengthened by an additional beam, the combination beam is better than the  composite beam, and steel is better than wood so far as strengthening material is concerned; 3) bending capability of “I-section” type of composite beam or combination beam of Chinese ancient buildings changes little compared to that of rectangular section type, which reflects its rationality.

Keywords:wooden structure; composite beam; combination beam; stress distribution; Chinese ancient building

*文化部科技创新项目（17-2009）。

作者简介：周乾，博士研究生，高级工程师，Email：zy_7225@yahoo.com.cn。

参考文献

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