《营造法式》转角构造新探

A New Investigation into the Corner Structure Specified in Yingzao Fashi

学界关于《营造法式》转角做法的考察多停留在实例比对的定性研究阶段,对文本信息反映的空间构造与数理关系则较少推导。本文围绕《营造法式》“功限”部分记载的大量角内构件长度数据,通过作图分析其具体所指(是实体长还是投影长,是边缘长还是中线长),进而反证李诫的数据录述逻辑。通过角内空间容纳角昂、角梁、衬角栿等构件的能力,证明大角梁斜置是《营造法式》默认的结角方法,并对殿阁与厅堂构造的山花处理、角梁收尾等内容展开对比考察,从而在分析文本所录构件长度数据的基础上,尝试深化对北宋官式建筑结角规律的认识。

Previous studies investigating the corner have mostly relied on comparative analysis of Song building standards(Yingzao fashi)with actual buildings,but they have neglected the constructional and mathematical relationships specified in the historical text.By using the rich information on inner-corner component length contained in the Gongxian chapters,this article clarifies the specific meaning of each entry(actual or projection length;side or axial length)and,through re-drawing of the components,demonstrates the inconsistent logic behind the historical data recording.In addition,the article identifies the oblique placement of the large corner beam as Yingzao fashi’s standard method,because only then was the corner space large enough to accommodate the various corner components.Finally,the article explores the triangular gable space of palatial structures(diange)and less eminent halls(tingtang),as well as their corner beam finishing.All of this is helpful to understand the system of corner rules in official government-sponsored construction of the Northern Song dynasty better.