THE EXISTING EARLIEST OVERPASS AND
CATENARY STONE AND ARCH BRIDGES
Luo Guanzhou
Ding Dajun
(Highway Administration of ShaoxingRegion,
(Nanjing Institute of
Zhejiang Province, Shaoxing, 312000)
Technology, Nanjing, 210096)
1. Simple Introduction
According to the statistics at the end of 1993, there were 10610 bridges in
Shaoxing Region, Zhejiang Province, China, so Shaoxing is called “ the Region of
Ten-Thousand-Bridge”.
Up to 1989, many bridges had been buried under soil, but many modern bridges
have been completed. Following statistics, in Shaoxing County there are 3.43 bridges
in every km2, as compared with Italian Vinice, there were 378 bridges before 2nd War
in area of 567km2. It can be seen that the distribution density of bridges in the former
was 5.2 times in the latter. Now, there are 604 ancient bridges and the most are stone
ones, among which 13 ancient bridges before Song Dynasty (960-1279), the earliest is
Guangxiang Bridge constructed firstly in East Jin (317-419), 41 constructed in Yuan
(1279-1368) and Ming (1368-1644) Dynasties, 550 in Qing Dynasty (1644-1911).
In this article, two categories of special ancient bridges are briefly introduced,
i.e. stone arch bridges with the embryonic form of overpass and stone arch bridges
with catenary axis.
2. The earliest overpass
In China, some newspapers and periodicals made wrong report for introducing
the Bazi (Chinese character of eight) Bridge (Fig.1) in
Fig.1 Bazi Bridge
Shaoxing City to be the existing earliest overpass in China.
This Bridge was constructed in the 4th year of Baoyou, Song Dynasty, i.e., in 1256, it
is a stone beam bridge but was wrong introduced to be an arch one. It is called Bazi
Bridge because the stepped stone bridge slopes at east and west ends in the south are
standing in oblique directions just to form a Chinese character of eight. The Bazi
Bridge was wrong reported as an overpass might be possible because in a famous
book of “Shaoxing Stone Bridges” made a mistake that the towpaths “on the
northsouth slop at the east end of” Bazi Bridge was wrong introduced as “under the
bottom” of it. Yet this Bridge is the existing earliest city bridge. The 1st author has
pointed out that the near Guangning Bridge of 7-fold stone Fig.2 Guangning Bridge
arch bridge (Fig.2) constructed also in Song Dynasty with a
distance of 136m in the north of Bazi Bridge can be considered as the existing earliest
embryonic form of overpass, because under this Bridge there are towpaths which can
be also used for walk.
The distance between Dongshuang Bridge (stone arch) in the south of Bazi
Bridge is equal to 147m, and that from the former to
Fig.3 Local map of Shaoxing
Fangche Bridge (stone beam) equal to 154m, i.e., in
City (in the northeast part)
1
the field of 437m, there are 4 ancient stone bridges (Fig.3, in which, the other Chinese
are not translated), it can see that the distribution density of bridges in local area is
much more large. These 2 bridges are also constructed in Song Dynasty.
3. Ancient stone arch bridges with catenary axis
The 1st author has discovered in Zhejiang Province, there are 6 ancient stone
arch bridges with catenary axis curves, among which 2 are located in Shaoxing
Region: Yingxian Bridge (Fig.4) with span of 14.70m in
Fig.4 Yingxian Bridge
Xinchang County, in the Annals of Shaoxing County,
edited in the years of Chenghua (1465-1487), Ming Dynasty, had been recorded and
was re-constructed in the 24th year of Daoguang (1544),
Fig.5 Yucheng Bridge
Qing Dynasty; Yucheng Bridge (Fig.5) with span of
12.00m in Shengzhou, constructed in the 16th year of Daoguang (1836), Qing Dynasty.
For Yingxian Bridge, in the following table, there are shown the measured coordinates
of arch axis, which approach to those calculated with a constant 6.530 of catenary
curve by using electron brain. The measured coordinates of the arch axis of Yucheng
Bridge are neglected here, which approach also to those calculated with a constant
9.889 of catenary curve. These results were obtained by the 1st author.
Besides, in Zhejiang Province, there are also discovered 4 bridges being
possible according to primary estimation to have arch exes of catenary or ellipse, they
are two, Fenggan Bridge and Guanyin Bridge in Tiantai Region; Guohe Bridge in the
Scenic Spot of Yandang Mountain, and the other one with unknown bridge name near
the National Highway 104 in Leqing County. The arch axes of these 4 bridges will be
measured recently in plan.
No.
of
Springing
section
crown
1
2
3
4
5
6
7
8
9
10
11
0
12
springing
Coordinates
1.0000
0.7758
0.5951
0.4507
0.3349
0.2428
0.1700
0.1133
0.0701
0.0384
0.0163
0.0041
0.0000
of arch axis
2