THE Jinding, Jintang, Mingzhu and Qianshan stations of the Intercity Mass Rapid Transit (MRT) have been completed and basic framework is under construction. However, the location of Zhuhai Station in Gongbei remains unsettled, according to Wu Haitao, chief engineer of the construction headquarters of China Railway No. 8 Engineering Group Co Ltd.

The three-storey Mingzhu Station, with the ground floor serving as a dual six-lane road, the first floor containing a spacious waiting lounge and business area and the second floor the railway platform, will be connected by escalators. The first floor, 230m long and 42m wide with total area of 9,660sqm, is 1.6 times the size of a standard football pitch.

Apart from being a commuter artery, the MRT will provide a rather scenic tour through the cities along the line which itself features similar structures but different designs, Wu explained.

Some 75 per cent of the total investment in the MRT Zhuhai section has been utilized while the Fenghuang Mountain Tunnel was completed in June 2007. Construction is completed on 93 per cent of the pile foundations and 78 per cent of the pier columns.

The main line of the MRT is 116.9km long with 17 stations -- New Guangzhou, Chencun, Beijiao, Shunde, Shunde University, Rongqi, Nantou, Xiaolan, Dongsheng, Shiqi, Zhongshan, Cuiheng, Jinding, Jintang, Mingzhu, Qianshan and Zhuhai.

The trains are expected to start running in 2010. The light rail will operate from 6am to midnight with short-term daily capacity of 395,000 passengers and long-term capacity 557,000 passengers. It will take merely 40 minutes for nonstop and 76 minutes for all-stop travel to Guangzhou. The ticket price is set at 50 yuan ($7.32) with probable buoyancy upon completion.

Unique design
The uniquely designed 22m main bridge over the Xiaolan Watercourse in Zhongshan, the longest span in the project, stands out because it is an arch consisting of a continuous girder of V-shaped steel tubing.

The 7,686.57m Xiaolan Watercourse super large bridge, crossing Nantou, Dongfeng, Dongsheng and Xiaolan towns in Zhongshan, is one of the bottleneck projects of the MRT. It requires 217 bridge piers, 1,816 piles and six continuous girders.

The two V-shaped bridge piers are the most difficult to construct, as it is more likely to result in cracks in the bearing platform at the foot of the pier, Wu Shimin, chief engineer of the project headquarters of China Railway No. 2 Engineering Group Co Ltd, explained. Temporary rest piers and inhaul cables have been installed to direct pressure away from the bearing platform. The two V-shaped bridge piers have been completed, Wu said.

Spectacular bridge
The most-spectacular continuous girder is the Shalang Super Large Bridge in Xiaolan of Zhongshan, with the 125m span crossing 105 National Highway and Zhongshan-Jiangmen Expressway, looking like a three-storey flyover. The span is the longest among the continuous girders of the railway on land. A 75m long side span, which is considered long enough in constructing continuous girders, has been designed on each side of the main span. The two ends of the bridge are expected to be connected by the end of the year.

Trackway bridge
The bridge crossing the Ronggui Watercourse, with main span reaching 185m, is the only non-gravel trackway in the MRT and the longest-spanned non-gravel continuous rigid frame bridge in China. With highly demanding engineering technology and no experience for reference, the bridge is very difficult to construct, Chief Engineer Gong Wentong explained. The two ends of the bridge¡¯s main girder will be connected next April, he noted.

Progress of works
Comprehensive No. 1 section: The 43.1km line from New Guangzhou to Xiaolan in Zhongshan, with total investment exceeding 4.02 billion yuan ($589 million), is under construction with 53.5 per cent of the total investment finished. Some 53.8 per cent of the bearing platforms and 45.8 per cent of the bridge piers have been completed while 17.4 per cent of the girder components are manufactured and 5.5 per cent of them assembled. The 325m Dongning Port Tunnel has been finished. It is being constructed by China Railway No. 3 Engineering Group Co Ltd.

Comprehensive No. 2 section: Running 18.8km from Xiaolan Station to Shiqi Station as the main line and 26.8km from Xiaolan to Xinhui as sub-line, the section has just one-fourth of the investment left with 84 per cent of pile foundations, 79 per cent of bearing platforms and 71 per cent of bridge piers completed. It is being built by China Railway No.2 Engineering Group Co Ltd.
Comprehensive No. 3 section: The line, with two tunnels, eight culverts and eight stations, runs 38.3km from Shiqi Station to Zhuhai Station. China Railway No. 8 Engineering Group Co Ltd is responsible for the construction.