New insight into an ancient stone arch bridge—The Zhao-Zhou Bridge of 1400 years old》.pdf.pdf

Int. J. Mech. $ci. Vol. 29, No. 12, pp. 831 843, 1987 0020-7403/87 $+ .00 Printed in Great Britain. 01987 Pergamon Journals Ltd. NEW INSIGHT INTO AN ANCIENT STONE ARCH BRIDGE-- THE ZHAO-ZHOU BRIDGE OF 1400 YEARS OLD QIAN LING-XI Research Institute of Engineering Mechanics, Dalian Institute of Technology, Dalian, The People's Republic of China (Received 12 May 1985) Abstract--In this paper an analysis is made for the old Zhao-Zhou Stone Arch Bridge on its carrying capacity based on structural limit analysis. For a stone arch bridge, with a given arch centre line and a given loading condition, there exists a minimum thickness limit for the arch ring. If the actual thickness of the arch ring is less than or equal to that limit, the stone arch will collapse as a result of the development of more than three hinges. The ratio of the actual thickness and the minimum limit characterizes the safety of the arch bridge under that loading condition. A calculation is made in this paper of the minimum thickness limit of the Zhao-Zhou Arch Bridge and its safety factors under a live concentrated load of 10 tons. That ancient bridge with 1400 years of history is shown to be very similar to a modern arch bridge in its appearance and is proved by the calculation to be in good accordance with the modern bridge building science. 1. INTRODUCTION Zhao-Zhou Bridge, which is also named the An-Ji Bridge, is located on the River Xiao, km to the south of Zhao County, Hebei Province. Some ancient literature indicates that it was built by Li Chun, a famous stonemason in the Sui Dynasty, around . 590-600 [1]. This ancient stone arch bridge has outlived about 1400 years of the elements, earthquakes and floods. It also miraculously survived a severe fire during its history. Though there were some repairs made at different periods, none were very significant ones, and were made for "small fissures between stones and slight surface frettings of iron keys" or just for local s