The Structure of Chinese Timber Architecture Twelfth century design standards and construction principles

This thesis examines the building standards and construction principles prescribed and used in the construction of state buildings of the Song Dynasty (960 - 1279), China, from the viewpoint of architectural design. It aims to answer three fundamental questions: (1) What measuring system was used in the carpentry design and construction? (2) What building scales and proportions were prescribed for and used in state buildings of the time? (3) What were the interrelations of the structural patterns and roof types, and what were their relationships to the building scales and proportions? The thesis begins by providing detailed explanations of the highly refined and unique Song period modular system which governed not only the sizes of each individual elements, but also the dimensions of structural grids and the proportion of entire building. This type of modular design was associated with a range of standard designs. Additionally, the construction methods for assembling and joining were also standardized. In brief, the state building structures of the Song period were standardized and typified. The thesis provides ample evidence for the argument that the Song design system consists of three coherent and interlocking systems, namely: Eight grades. Cross-sections of structural elements were ranked into eight standard grades.New opinions have been suggested as to the interrelationships between the eight grades, which deal not only with the division methods, but also with certain ratios, which unite these basic sizes into an organic whole. The thesis demonstrates that Grade III (the mostly commonly used) was the fundamental unit by which the sizes of others were derived. Modular grid. Critical structural elements affecting building layout and proportions - such as beam, rafter and column module - are examined. The use of modules based on the Elementary Grade and related to the structural type and bracketing unit (puzuo) are clarified. Building proportions. The size and proportion of a building were governed by the Elementary Grade, structural arrangement and roof type. In addition to analyzing the relationships between essential structural requirements and architectural proportions, the thesis exposes the interdependence of roof type and the length-to-width ratio of the building proper (the building proper indicates the building excluding the roof and the podium). The thesis studies the five principle structure types: Diantang (Palace type), Tingtang (Mansion type), Fengguo (Palace-mansion type), Yuwu (Ordinary-house type) and Tingxie (Pavilion type), as well as multistory buildings and annexes. It goes on to elucidate the problem of structural definitions, applications and methods of construction. Twenty-seven ancient buildings built between 782 and 1357, judged alongside the oldest existent building code, Yingzao Fashi (The State Building Standards, Song Dynasty, printed in 1103), serve as the visual and literary evidence for this study. The thesis includes 110 drawings which serve as the architect's principle language. An annotated translation of Chapters 4 and 5 of the Yingzao Fashi, and a descriptive translation of 171 fundamental Chinese architectural terms, mainly drawn from the Yingzao Fashi are appended to the main body of the thesis at the end of the thesis.