Nanjing: Forty-nine years ago, beside the construction site of the Wuhan Yangtze Bridge - the first ever bridge across the country's longest river - Chairman Mao Zedong waxed lyrical with one of his most remembered poetic lines, "A bridge will fly to span the north and south, turning an immense chasm into a thoroughfare."

In technical terms, however, the bridge that had thrilled one of the founding fathers of New China is somewhat old hat today, as the 6,300-kilometre-long mighty Yangtze has since been spanned by even larger and stronger feats of civil engineering ingenuity.

On May 1, the Runyang Bridge linking Zhenjiang and Yangzhou, two cities in Jiangsu Province - a twin-bridge complex, opened to traffic, bring the number on the Yangtze's navigable section to 39.

On its northern side, the Runyang has a stayed-cable bridge linked by a central aisle to a suspension bridge running on the south side.

The suspension bridge boasts a 1,490-metre span - the world's third longest after the Akashi Kaikyo of Japan and the Great Belt of Denmark.

"A single span of Runyang is about the whole length of the Wuhan bridge which had to be built on many piers," Wu Shengdong, director-general of the Runyang project, told China Daily. "The materials and engineering technology available today are far superior to 50 years ago," he said.

The bridge-building history of China is long and impressive.

Zhaozhou Bridge, built around 600 AD in the northern province of Hebei, is perhaps the oldest stone-arch bridge in the world. It is also a living textbook to students of classic architecture, in particular the arch structure which shifts the weight to the bank.

Bridges are considered more important than any other surviving examples of Chinese architecture. As the old saying goes, "Better to tear down 10 temples than ruin one bridge."

However, nearly all of the country's modern suspension bridges, which have long spans and limit navigation, were built in the past 15 years amid a booming economy and growing need for better infrastructure.

The first major stayed-cable bridge was the Nanpu Bridge, with a 423-metre span length, across Shanghai's Huangpu River. It was finished in late 1991, after the central government decided to turn the suburb of Pudong, east of the river into a world-class metropolis.

Today China has more than 100 bridges with a span length over 200 metres. They come in different architectural shapes - arch, beam, or suspension.

It is hard to tell when and where a new record is to take place, as bridge architects and engineers seem to be tireless in their desire to build longer, wider and greater weight-bearing ones.

Before Runyang, the Jiangyin Yangtze Bridge - built in 1999 and also in Jiangsu Province, was the country's longest at 1,385-metre span - just 25 metres shorter than Britain's engineering spectacle, the Humber Bridge.

"China's bridge engineering technology has made major progress in the past 15 years," said Feng Maorun, chief engineer of the Ministry of Communications.

He said the Yangtze bridges in Jiangsu are extraordinary feats of civil engineering, in that the river runs wider and deeper in this eastern province where it nears the sea. Runyang is the creme de la creme of China's bridge building, he added.

Economic benefits

"Transportation is of major importance for promoting social development, and it is imperative to have more excellent projects like this," said Feng.

In local people's eyes, a new bridge means a lot to their future. "In the past, you had to wait for ferries to cross the river, a wait that could be both long and annoying," said Chen Lihong, a girl from Zhenjiang, pointing to Yangzhou on the opposite shore.

Since the Runyang opened, it now takes about 10 minutes to drive across the Yangtze with the two-way, six-lane twin bridges.

"Now that the great bridge is here, the two cities are destined to grow bigger and bigger," said Chen.

With slip roads joining expressways to Beijing, Shanghai, Nanjing and Hangzhou, the Runyang Bridge is designed to make the two cities and their neighbours in Jiangsu's less-affluent north and central areas closer to their big brothers, in particular, Shanghai.

Yangzhou, three hours drive west of Shanghai, posted a per capita GDP of US$2,000 or so last year, compared to more than US$5,000 in Suzhou, which is next to Shanghai, and has surpassed Shanghai to become the country's top destination of foreign direct investment.

"The province has an expressway network that links every city, so basically we have no problem travelling to Shanghai and Nanjing through bridges in other places," said He Weihua, deputy director of Yangzhou Bureau of Communications on the north bank of the Runyang Bridge.

"But having a bridge of our own certainly makes a great difference in attracting investors and stimulating the economy," he told China Daily.

Breaking records

The Runyang Bridge tells its own tale through the handful of records it has made. In addition to a super span length, it boasts the country's largest anchor ingot which pegs the bridge to the river bed, the longest main cables that suspend the roadway, and the tallest bridge towers which hold the cables.

The steel wires which form the suspension bridge's 91-centimetre-thick main cables, could circle the Earth three times if unravelled and stretched end to end.

"The difficulties of this project were huge and almost every link of the construction embodies innovation," said Pan Yonghe, director of the Jiangsu Provincial Bureau of Communications. "The thing we're most proud of is that its design and construction is solely Chinese," he added.

The Ministry of Communications and the provincial government jointly oversaw the construction of Runyang, a key infrastructure project of the central government's development plans. The 5.78 billion yuan (US$698 million) construction costs came from the national coffers, local tax revenue, and bank loans.

"It was a great experience working here because what we worked on was the newest in the country and in many ways beyond what we learned at school," said Shao Boxing, a young electrical engineer who has been employed on the project since graduating two years ago.

He is responsible for the ventilation system which pumps dry air into the cables to reduce humidity and prevent the steel inside from rusting, and the lighting which makes the twin bridges so colourful at night.

But, as the old adage goes, the road to greatness is hard. In the past four years of construction, many of the workers, including director-general Wu, spent their Spring Festival holidays on the construction site, and some key workers postponed their weddings. On a more cheery note, a number of newborns whose parents were employed on the project named their offspring Runyang.

"The spiritual accomplishments of the Runyang Bridge are as great as its material merits," said Pan from the provincial bureau. So far there have been no reports of corruption relating to the project.

More bridges

But the inventiveness of the nation's civil engineers seems boundless, and bridge experts are looking towards even more spectacular projects.

Nanjing, the Jiangsu provincial capital, which already has two bridges across the Yangtze, is on track to finish a third this year. And in the pipeline are plans for a couple more and also tunnels. For the first time in China, Nanjing's third bridge uses steel towers, which are stronger and lighter, but more expensive than traditional concrete.

"The river is not very wide in the place where this bridge stands, and I think that's why steel towers are affordable," said Ji Lin, a senior engineer on the Runyang project.

Some 200 kilometres down river from Nanjing, the two towers of a stayed cable bridge linking Suzhou and Nantong are already in place. They will support the world's longest 1,088-metre cable-stayed span, surpassing the current stayed cable champion, the 890-metre-span Tatara in Japan.

In the neighouring province of Zhejiang, a trans-straits suspension bridge will link the two coastal cities of Ningbo and Zhoushan by 2008. Once complete, its 1,650-metre span will make it the world's second longest suspension bridge.

Zhejiang's capital Hangzhou is also building a giant bridge running 36 kilometres across Hangzhou Bay to Ningbo. That bridge will be open to traffic in 2009, under current plans.

Not to be outdone, Shanghai, currently the world's second largest port city, is building a 31-kilometres long bridge linking the city to its about-to-complete deep water Yangshan Port, designed to be a world-class logistics hub.

"Major infrastructure projects like the Runyang Bridge are important not only to the local economy, but also to the overall development of the country," said Wang Keqiang, a professor of macroeconomics with the Shanghai University of Finance and Economics.

"But it also takes a great amount of money and fine techniques to make them," he said. "That's why we have the old Chinese saying that 'Bridges are the babies of boom'."

(China Daily 05/12/2005 page13)