Quickly fix and repair Nam Cuong bridge on Noi Bai - Lao Cai expressway

Due to the impact of recent heavy rains, Nam Cuong bridge on the Noi Bai - Lao Cai highway has collapsed, cracked and damaged, threatening traffic safety, reducing its operational capacity and affecting surrounding residential areas.

A representative of the Road Management Area I (Vietnam Road Administration) said that due to the impact of storm No. 3 (2024) and subsequent floods, Nam Cuong bridge Km251+031 (right) on the Noi Bai- Lao Cai expressway (in Lao Cai province) has collapsed and been damaged. Currently, at abutment M1, a slide has appeared starting from near the top of the hill on the right side of the road at the beginning of the bridge after the abutment down to the road surface, about 6.5m from the expansion joint of abutment M1.

This crack continues to run through the center of abutment M1 (right of the line) and down to the ground under the bridge span N1, the slope roof, the crack is about 10cm wide, causing the cone of abutment M1 to sink about 20cm. At the position of abutment M1, the girder span structure has pressed against the position of the anti-shove pier on the abutment. Through the survey, the sliding arc area has affected the residential area around the bridge, causing property damage, and potentially threatening safety.

In addition, the concrete support pile at the position of girder 4 and girder 5 also cracked due to the horizontal connection of the girder head and girder rib pressing against the support pile. At the position of girder 4 and 5, there was a slight cracking phenomenon. The road at the end of the bridge at the end of pier M1, before the time of the survey, there was damage to the road surface subsidence about 7.2m from the expansion joint, 6.3m long towards the road at the bridge head, the asphalt concrete crack was about 3.5cm wide.

“The bridge deck on span N1 has a horizontal crack at a position about 2.4m from the center of the top of pier P1. The crack appears from the right side barrier and extends to near the left side barrier. The widest point is 4cm. The crack's depth has reached the concrete layer of the bridge deck and separates the concrete barrier block at the crack's location. In addition, the bridge deck has also shown signs of wear due to long-term exploitation.

At the M1 pier and T1 pier, the bearings were damaged and displaced, especially the single-directional basin bearings at the M1 pier were severely damaged, the upper plate of the bearings lost connection with the steel plate of the beam bottom. The bearings at the T1 pier were steel-core rubber bearings, the G4 and G5 bearings were displaced and slid off the support stone towards the pier", the representative of Road Management Area I assessed.

To ensure construction safety and traffic safety on the route, Road Management Area I has prepared a technical economic report proposing a plan to repair Nam Cuong Bridge, including repairing the bridge deck and the bridgehead road. The bridge deck cracks in the area of ​​pier T1 will be supplemented with 2 expansion joints on pier T1, drilled and installed expansion joint reinforcement, then re-poured with non-shrinkage concrete.

Survey and assess damage and cracks at Nam Cuong bridge area.

For damage at the M1 pier area, the pier cap beam will be repaired and the broken concrete areas will be chiseled out, patched with non-shrinkage concrete mortar. After jacking up the beam to replace the bearing, the entire concrete part of the anti-shove pier at the M1 pier will be demolished... For the landslide area, the slope protection will be reinforced with reinforcements such as: digging to lower the load, reinforcing the ground anchors, ground nails, underground drainage, surface...

During the repair period, to ensure safe operation of Nam Cuong Bridge, Road Management Area I has organized traffic flow: For passenger vans with more than 9 seats, trucks under 10 tons from Hanoi to Kim Thanh, Lao Cai, take the highway to IC18 intersection (Binh Minh), turn onto Binh Minh street, go to National Highway 4E (Tran Hung Dao Avenue), turn left onto Phu Thinh street, then turn right onto Le Thanh street to National Highway 4D and then to IC19 intersection.

In the opposite direction, from the highway, go to IC19 intersection, take National Highway 4D, then turn left onto Le Thanh Street, then turn left onto Phu Thinh Street, continue to turn right onto National Highway L4E (Tran Hung Dao Avenue), take Binh Minh Street, pass IC18 intersection onto Noi Bai-Lao Cai Expressway.

Passenger vans with less than 9 seats, pickup trucks, trucks over 10 tons or semi-trailers can still travel on the highway, without being routed through the city. The Nam Cuong bridge right branch and the Km250 tunnel are open to traffic in two directions, with one lane in each direction.

The functional unit closes the left branch from Km248+500 to Km251+700, these are two locations where the median strip opens and the start of two separate directions of travel.

The right branch of the route is used to ensure traffic, the motor vehicle lane is built with a soft median strip made of painted plastic pipes and covered with reflective paper, the base of the columns is made of concrete, the distance between 2 columns is about 2.5-3 m, connected by reflective wire. The functional unit also arranged all kinds of barriers, signs, lighting, night lights, set up checkpoints at both ends to separate the flow, there are people to ensure traffic and patrol continuously 24/24 hours.

nhandan.vn

Source: https://baolaocai.vn/som-khac-phuc-sua-chua-cau-nam-cuong-tren-tuyen-cao-toc-noi-bai-lao-cai-post886372.html