［提要］北京金地中心工程塔楼A，B为满足建筑净高要求，采用了跨度为12.245m和10.225m，两端为简支的钢筋混凝土楼面次梁，跨高比分别达到20.4和22.7。介绍了该大跨高比且大跨度楼面次梁的设计。为研究该楼面梁的刚度及开裂性能，进行了足尺构件试验，按有关规范进行了计算。结果表明，该楼面梁的裂缝宽度及挠度均小于规范限值。根据试验结果，对设计和施工提出了有针对性的建议。该工程主体结构已完成施工，未发现其楼面次梁有显著可见的裂缝。

［关键词］钢筋混凝土楼面次梁；大跨高比；足尺构件试验；裂缝宽度；挠度

Design and Test of Large Span-to-height Ratio and Large Span RC Floor Beams/Zhao Yiqiang¹，Ke Changhua¹，Cheng Maokun¹，Qian Jiaru²，Zhao Zuozhou²，Dai Fucong²，Huang Xiaokun³，Liu Weimin⁴，Tong Xiao ou⁵，Liu Zheng⁵

/(1 Beijing Institute of Architectural Design, Beijing 100045,China；2 Department of Civil Engineering, Tsinghua University, Beijing 100084,China； 3 China Academy of Building Research, Beijing 100027,China； 4 China Construction First Group Fifth Construction Company, Beijing 100024,China； 5 Beijing Goldfield Development Co., Ltd., Beijing 100026，China)

Abstract: To satisfy the clear height requirement, the span to height ratios of 20.4 and 22.7 were adopted for the simply supported reinforced concrete secondary floor beams with span of 12.245m and 10.225m respectively for tower A and B of Beijing Goldfield Center. The design of these large span to height ratio and large span secondary floor beams is presented. To study the behavior of the secondary beams under the serviceability limit state, field test of a full scale specimen was carried out and calculation was performed according to design codes. The results show that both crack width and vertical deflection can meet the code requirements. Based on the test results, recommendations are presented for design and construction. The structures of tower A and B have been completed and no obvious cracks on the secondary floor beams have been found.

Keywords: RC secondary beam； large span to height ratio； full scale specimen test； crack width; deflection

1)北京市建筑设计研究院，100045；2)清华大学土木工程系，北京，100084；3)中国建筑科学研究院，北京，100027；4)中国建筑第一工程局第五建筑公司，北京，100024；5)北京金地鸿业房地产开发有限公司，100026。