腹板开洞竹木工字梁受力性能的试验研究  

Experimental Study on Mechanical Performance of OSB Webbed Bamboo Ⅰ Shaped Joist with Web Openings

作　　者：陈国[1] 张齐生[2] 黄东升[1] 李海涛[1] 

机构地区：[1]南京林业大学土木工程学院,江苏南京210037 [2]南京林业大学材料科学与工程学院,江苏南京210037

出　　处：《湖南大学学报（自然科学版）》2015年第11期111-118,共8页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51408312);江苏省自然科学基金资助项目(BK20130982);中国博士后基金资助项目(2013M541679;2014T70528);江苏省博士后基金资助项目(1301017A);江苏省高校自然科学基金资助项目(13KJB560008);江苏高校优势学科建设工程资助项目~~

摘　　要：以洞口尺寸、形状和净距为参数,对28根开孔梁和2根实腹梁的力学性能进行了试验研究与对比分析,研究其破坏形态及破坏机理等,并与未开孔梁的试验结果进行对比.提出了基于费氏空腹桁架理论的开孔梁承载力计算公式.结果表明,开孔梁内的应力分布、挠度变化不再完全符合传统弯曲理论.随着径腹比的加大,开孔梁的承载力和刚度呈显著下降趋势.方孔梁的承载力略大于外接圆孔,以外接圆孔代替方孔梁的承载力偏于安全.对于径腹比为0.5的多洞口梁而言,当方洞和圆洞净距分别大于2倍和2.5倍孔长时,可忽略洞口间的相互影响.通过对比分析,理论结果与实验结果的误差平均值为15%左右,从而验证了修正后的空腹桁架理论计算公式的准确性和可靠性.The effect of parameters, such as the size, shape and clear distance of holes, on the mechani- cal performance of the joists was analyzed experimentally. Compared with 2 joists with no web holes, a to- tal of 28 OSB webbed bamboo joists were tested to failure to investigate their failure modes and failure mechanism. Based on the-Vierendeel truss theory, the design formula of the composite joists was presen- ted. It was found that the holes changed the stress distribution in the webs and the deflection did not con- form to the traditional bending theory. With the increase of the ratio of height to web height, the load car- rying capacity and stiffness of the joists with holes decreased significantly. A web hole with sharp corners had a bigger negative impact on strength than a circular hole of similar size. The results from the tests on I shaped joists with two circular and two square web holes with a size of 50 percent web depth showed that the critical clear distance was about 2 times and 2. 5 of the web hole size respectively. The comparison showed that the error between the theoretical results and the experimental results was about 15%, verif- ying the accuracy and reliability of the revised formula of Vierendeel truss theory.

关 键 词：竹集成材 腹板开孔 工字梁 受力性能 破坏机理 费氏空腹桁架理论 

分 类 号：TU366.1[建筑科学—结构工程]