The first steel cofferdam of the main bridge of Dongming Yellow River Bridge was successfully poured into the left side of Tanbaoshan Tunnel of Wuzhen Expressway in Chongqing. These are the events of

The first steel cofferdam of the main bridge

of Dongming Yellow River Bridge was successfully poured into the left side of Tanbaoshan Tunnel of Wuzhen Expressway in Chongqing. These are the big events in the bridge world today. The first steel cofferdam of the main bridge

of Dongming Yellow River Bridge was successfully poured

recently. The first steel cofferdam of the main bridge of Dongming Yellow River Bridge was successfully poured. The steel sheet pile cofferdam of 61 # pier of the main bridge was located at the main stream of the Yellow River. The cofferdam was 26.035 meters long. 21.2 meters wide. The main bridge

across the Yellow River is the key control project of the project, with a total length of 7620 meters, adopting the technical standard of two-way six-lane first-class highway, of which the Yellow River Bridge is 5781 meters long, the south approach is 1082.39 meters long, and the north approach is 756.68 meters long. The completion of the new bridge will effectively relieve the transportation pressure of the existing bridge, promote the formation and development of the regional economy, and improve the living standards of the people; it will also play an important role in improving the regional road network layout, promoting the economic and social exchanges between Shandong and Henan provinces, and promoting the safe and convenient travel of the people. (Source: official account of CCCC Third Highway Engineering Co., Ltd.)

02

The left side of Tanbaoshan Tunnel of Chongqing Wuzhen Expressway was completed

. Recently, after more than 1290 days and nights of hard construction, the left line of Tanbaoshan Tunnel of Chongqing Wuzhen Expressway was successfully completed.

Wuzhen Expressway starts from Wuxi County, Chongqing, and ends in Zhenping County, Shaanxi Province, with a total length of 48.69 kilometers. It is constructed according to the standard of two-way four-lane expressway, with a bridge-tunnel ratio of 90.6%. It is the second expressway corridor directly connecting Chongqing with Shaanxi Province, and also the highest bridge-tunnel ratio expressway in Chongqing at present. It started construction on November 27, 2018 and is scheduled to open in 2023. By then, the journey between Wuxi in Chongqing and Zhenping in Shaanxi will be shortened from 3.5 hours to less than 1 hour. The total length

of Tanbaoshan Tunnel is 4616 meters. It is designed as a double-hole two-way four-lane tunnel with a net width of 10.25 meters and a net height of 5 meters. It is a gas tunnel and a key control project of the whole line. The entrance end of the tunnel is located below the riverbed of Zhongba River, with perennial running water. The top of the tunnel is only 2 meters away from the bottom of the riverbed. It is extremely difficult to enter the tunnel. After entering the tunnel, it faces special and complex geological conditions such as water gushing, gas, karst and goaf. The exit end is located in the high mountains and deep valleys, connected with the Dongxi River Bridge, and the construction is difficult.

In the construction of the tunnel entrance, in order to ensure the construction safety, the project department has equipped the tunnel entrance with intelligent systems such as access control management, personnel positioning, video surveillance, gas monitoring, cable broadcasting, etc., to enable construction and production through intelligent construction. In order to ensure the safety of high-voltage power supply, TN-S system is used for power supply outside the tunnel, IT system is used for power supply inside the tunnel, and mining explosion-proof flexible cables, electrical equipment, switches, lighting fixtures, etc. are used for all transmission lines to reduce safety risks. In order to solve the problem of the complex geology of the tunnel undercrossing the river, the leading group of the project took turns to be on duty on the spot. Through many measures, such as the relocation of the river, the reinforcement and grouting of the surrounding rock, and the driving of the advanced pipe shed, the construction team and the input of mechanical equipment were increased, and the continuous fighting day and night created a monthly footage of 70 meters for the V-level surrounding rock, which greatly shortened the construction period. (Source: China Railway Construction)

03

The 890-ton steel truss girder of the New Tongyang Canal Bridge successfully "walked" 34.5 meters

from February 11 to 13. After three days of hard work, the second steel truss girder on the right side of the 890-ton New Tongyang Canal Bridge on the Beijing-Shanghai Expressway. It was pushed 34.5 meters horizontally and put in place safely. This marks a breakthrough in another key and difficult project of Jiangdu Bid 2 of Beijing-Shanghai Expressway Expansion Project. Xintongyang Canal Bridge

of Beijing-Shanghai Expressway, with a total length of 1125.11 meters, is a super-large bridge with a length of more than 1000 meters. The construction of the second main pier is an important control project and key node project of the bid section, with large construction volume, high safety risk and high technical difficulty. During the construction of bearing platform and capping beam in the early stage, various difficulties were encountered. The project department made every effort to plan carefully and implement fine management measures to properly handle the problem of "piping" and overcome the problems caused by continuous rainy weather.

According to reports, the steel truss girder with a span of 70 meters, a height of 1 meter, a main truss center distance of 21.8 meters and a total weight of 890 tons is a new through steel truss girder, which crosses the new Tongyang Canal waterway. In order to ensure the safe erection of the steel truss girder, the project department carefully reviewed the documents and drawings according to the actual process, comprehensively grasped the technical standards, organized on-site investigation, conducted detailed analysis and investigation on the steel truss structure of the bridge, the actual terrain of the site, and the traffic along the waterway, and drew on the experience of the left steel truss girder erection, invited experts to check the incremental launching scheme, and further optimized the incremental launching construction technology. The successful completion of this

construction provides a working face for the subsequent construction of bridge deck installation, wet joints, guardrails and bridge deck pavement, and takes a key step towards the full realization of the two-way eight-lane opening goal of the New Tongyang Canal Bridge. (Source: Yangzhou Daily)

04

Yilai Expressway Hefeng East Project Yunnan Zhuang Bridge ran out of "acceleration"

in the early morning of February 12, after continuous construction day and night. The key control project of Hefeng East Project of Yilai Expressway, the No.1 block of the right upper chord of the No.14 main pier of Yunnanzhuang Bridge, was successfully completed three days ahead of schedule.

Since the start of construction, the first phase of civil engineering of Hefeng East Project has been basically completed, and the second phase has been more than half completed, leaving only two special bridges, Yunnan Zhuang and Guishui River, which have not yet been completed. Among them, Yunnanzhuang Bridge is the first open-spandrel continuous rigid frame bridge in Hubei Province, the third in China and even in the world. Because of its unique bridge type, extremely complex process and extremely difficult construction, it has become a key control project restricting the construction period of the project. For the first time, the construction technology of "double-layer cable + hanging basket" is adopted in

Yunnan Zhuang Bridge. During the construction process, the upper and lower hanging baskets need to be set up respectively, and the upper temporary buckle tower should be set up. After 10 sections of hanging basket suspension pouring and temporary anchor construction, the triangular hollow area is formed and enters the confluence section, and then the normal suspension pouring construction is organized. Every step should be taken carefully.

Yilai Expressway (Yidu to Laifeng) is a key project in the 13th Five-Year Plan of Hubei Province, with four lanes in both directions, 180 kilometers in length and 80 kilometers in design speed. It is not only a green passage through Enshi Prefecture and Yichang City, but also an economic artery to promote rural revitalization in Wuling Mountain area. After the completion of the project, the travel time from Hefeng to Enshi, Yichang and Zhangjiajie will be shortened to 1.5 hours.