01
The entire TY-shaped piers of the Huangmaohai Bridge were completed
On July 5th, after 36 hours of hard work day and night, the control project of the Huangmaohai cross-sea passage project - the west transition pier and auxiliary pier of the Huangmaohai Bridge were successfully poured, marking the completion of all the project's whole TY piers, which is also the first application of the whole TY pier in the sub-section bridge of the mainland expressway.
The whole TY pier of Huangmaohai Bridge is divided into east and west sides, the maximum height of the cover beam is 60 meters, the length reaches 37.4 meters, and it is completed in three pouring, and the design of the large cantilever cover beam is relatively rare in the field of bridge construction, and it is also the most difficult sub-project in the project.
In order to coordinate and promote the safety, quality and progress of the cantilever construction of the TY pier cover beam with a length of 14.7 meters, the project technical research team comprehensively investigated and compared and simulated a variety of construction plans in three dimensions, and prepared a detailed whole-process monitoring implementation plan according to the characteristics of the force. Practice proves that the stress and deformation of the stent are less than the calculated theoretical value, and the intrinsic safety effect is remarkable.
During the construction process, the cover beam cantilever beam should be poured in three times, and the maximum pouring amount of a single time is 418 cubic meters, and the high-altitude large cantilever cover beam bracket is subjected to a large load and different force positions when poured, and the construction is extremely difficult.
In order to ensure the force of each working condition of the cast-in-place bracket and ensure that the tensile stress of the concrete and the force at the sub-section meet the design requirements, the project sets horizontal steel strands or fine-rolled rebar on the left and right brackets and tensions, and at the same time sets oblique, vertical and horizontal prestressed steel strands in the concrete poured in the segments, and implements tension according to the grading force needs.
Based on the special situation that the Y-shaped oblique leg inclination angle of the TY-shaped pier structure of the Huangmaohai cross-sea channel is 45 degrees, the internal steel bar structure is complex, and the workers have no working space and low construction efficiency in the process of rebar lashing, the project draws on the construction experience of the steel bar parts of the main tower of the "small man's waist", and divides the steel bar of the diagonal leg section of the TY pier into two large blocks for the overall prefabrication of the backyard and then hoisting, which greatly reduces the difficulty of steel bar lashing, and shortens the oblique leg section originally planned to be completed in 28 days to 18 days, improving the construction efficiency.
At present, the project has completed more than 83% of the contract amount, and the construction is smooth, and it is about to enter the lifting stage of steel box girder, opening a new chapter in superstructure construction, and it is expected that the main bridge can be completed in April 2024. (Source: Poly Big Engineering Co., Ltd.)
02
The bridge deck of the Dawan section of the Enguang Expressway collapsed
At 0:38 on July 6, the mountain rock around the No. 6 bridge in the direction of K230+679 in the Dawan section of the G5012 Enguang Expressway suddenly collapsed, and the boulder washed away the bridge pier pillars, causing part of the bridge deck to collapse.
The disaster caused spontaneous combustion after two vehicles were damaged, and three people were slightly injured, and the injured people were promptly sent to the hospital for treatment.
After the incident, all relevant units of highway management rushed to the scene as soon as possible. After the Dazhou fire rescue team was in place, the fire was quickly extinguished. 17 commanders and fighters of 3 combat vehicles of the Dazhou Comprehensive Emergency Rescue Detachment rushed to the scene of the accident with rescue equipment to conduct life detection in the collapse area, and no vehicles were buried and no signs of life were found.
After preliminary investigation on the spot, the cause of the incident was the sudden collapse of the surrounding mountains of the No. 6 Bridge, and the boulder washed away the single bridge pier pillar in the direction of Wanzhou to Dazhou, causing the bridge deck to collapse.
At present, the main line of this section has been closed and controlled in both directions, and all passing vehicles are diverted through the G65 Baomao Expressway Xujiaba Toll Station and the G5012 Enguang Expressway Panshi Toll Station. (Source: China News Network)
03
The Jingli Expressway in Hunan was completed and opened to traffic
On June 30, the Jingzhou-Liping Expressway in Hunan Province (referred to as the "Jingli Expressway") was officially opened to traffic. So far, the travel time between the two places has been shortened from 90 minutes to 45 minutes, and Xiangqian and Gui have added an interconnected high-speed channel.
The whole line of Jingli Expressway is located in the territory of Jingzhou Miao and Dong Autonomous County, Huaihua City, starting from Xinchong Junction, connecting with the Huaihua section of G65 Baomao Expressway, ending at the boundary plate of Xiangqian Boundary, connecting with the completed and opened Lijing Expressway in Guizhou Province through the boundary tunnel, the total length of the route is about 57 kilometers, using the two-way 4-lane expressway standard construction, the design speed is 100 kilometers per hour. Among them, the boundary plate route from the east of Pingcha Town in Jingzhou County to the Xiangqian border has a total length of about 15.9 kilometers, with a total of 9 bridges, 1 separated three-dimensional crossing, 2 separate tunnels and 55 tonghan.
The Three Pagoda Bridge is the longest bridge in the line, with a length of 757 meters, and is a continuous small box girder structure of 25×30 meters of prestressed concrete; The No. 3 Viaduct in Shangbao Village is the highest bridge in the whole line, with hollow thin pilaster piers, and the highest pier is 55.25 meters. In order to ensure the smooth construction of the bridge, the project team overcame environmental constraints such as complex terrain and geology along the line, long transportation distance of box girders, and overcame technical problems such as high pier girder and limited space girder at the junction of bridge and tunnel to ensure the smooth completion of the bridge.
Jiepai tunnel spans Hunan and Guizhou provinces, the left hole is 1520 meters long, the right hole is 1064 meters long, is the Jingli Expressway whole line control project, the surrounding rock of the tunnel is complex and changeable, multi-fault development fracture zone, easy to water inrush, in order to ensure the safety and quality of tunnel construction, the project team strengthened advanced geological forecasting, monitoring and measurement frequency, strict dynamic control, and finally overcame the problems of tunnel bias, karst cave, water inrush, etc., and realized the smooth breakthrough of the tunnel.
Jingli Expressway is the first batch of construction projects shortlisted for the "Ping An Centennial" quality project of the Ministry of Transport in Hunan Province, which is an important corridor for the interconnection of the three provinces of Xiang, Guizhou and Guizhou, and the completion and operation of the project will form a new high-speed channel in the area south of the Shanghai-Kunming Expressway, which is of great significance to accelerate the economic and social integration process of the counties and cities along the route. (Source: CCCC Second Aviation Engineering Bureau Limited)
04
The lower part of the main bridge of the Linyu Yellow River Bridge was completed
On July 4, with the successful completion of the construction of the last pier of the main bridge of the Linyu Yellow River Bridge, the construction of the substructure of the main bridge of the bridge has been completed, laying a solid foundation for the steel box girder of the bridge to push the dragon at the end of the year.
The Linyu Yellow River Bridge is a control node project of the G3511 National Expressway Hebao Line, and an important part of the "three vertical, twelve horizontal and twelve rings" in Shanxi Province, and the bridge has set a record in the forefront of the world in four indicators: continuous jacking length, maximum jacking length, synchronous control of jacks during jacking, and the use of weathering steel on a single bridge.
The total length of the bridge is 5427 meters, the main pier body has a total of 32, the average height is 76 meters, the largest pier height is 99 meters, the last pier body of this construction is 75 meters high, and the concrete square volume is 2753.8 cubic meters. The main pier is a single-box double-chamber thin-walled hollow pier, which is constructed by fully enclosed hydraulic climbing process, integrating formwork support and construction scaffolding platform; The pier cap construction adopts the combination of hydraulic climbing mold and shaped steel mold, using the climbing mold as the platform installation pier cap template, using the pier cap template as the platform to install the pier top working platform, and using the next layer of climbing mold as a platform when dismantling, which not only improves efficiency but also improves safety.
In order to efficiently complete the construction of the main pier of the bridge, the project team planned ahead of time, carefully deployed, combined with the weather forecast, and continuously optimized the construction organization; Organize on-site management personnel and labor teams to do a good job in safety training and technical disclosure of construction plans in advance, optimize the construction organization according to the actual situation of on-site construction, adjust construction dynamics in a timely manner, and schedule materials, equipment and personnel in a planned, organized and targeted manner to maximize the utilization rate of various resources such as "work, machinery and materials"; At the same time, the project strictly follows the requirements of construction standardization, and strictly accepts the indicators such as materials, steel bar spacing, and steel bar protective layer; Adhere to the test system, optimize the construction parameters and the best matching ratio of concrete, strengthen the supervision of the concrete construction process, ensure that the concrete is poured in layers, vibrating and compact, the construction rate is appropriate, and the influence of excessive hydration heat on the quality of concrete is avoided, and the quality and safety of pier construction are guaranteed.
After the project is completed and put into operation, it will connect with other highways to form a highway network that runs from east to west and north to south, and the opening time from Yuncheng City in Shanxi to Tongchuan City in Shaanxi Province will be shortened from 4 hours to 2 and a half hours, contributing to the ecological protection and high-quality development of the Yellow River Basin. (Source: China Railway Construction Bridge Bureau Group Co., Ltd.)
05
Jidayuan High-speed Railway (Shanxi Section) Fanjiazhuang Cross-Hanyuan Line Special Bridge took the lead in completing the construction of the substructure
On July 4, the construction task of the substructure of the Fanjiazhuang Cross-Hanyuan Railway Special Bridge of the Jidayuan High-speed Railway (Shanxi Section) was successfully completed, which was the first to complete the substructure construction of the special bridge of more than 18 kilometers on the entire line, one and a half months earlier than the original plan, laying the foundation for the completion of the box girder erection task of the whole line at the end of the year.
Jining connects Ulanqab City of Inner Mongolia Autonomous Region to the north via Datong-Yuanping High-speed Railway (Jidayuan High-speed Railway), which is the first high-speed rail channel connecting Datong, Shuozhou and Xinzhou in Shanxi with the provincial capital Taiyuan. The total length of the line is about 270.8 kilometers, of which the Shanxi section is about 197.134 kilometers.
Located in Xinzhou, Shanxi, the Fanjiazhuang Cross-Hanyuan Railway Special Bridge of the Jidayuan High-speed Railway is one of the most difficult projects of the whole line. The total length of the bridge is about 19.592 km, with three crossing railway lines and one crossing expressway.
In order to promote construction with high quality and efficiency, the construction unit conscientiously implements the dual prevention mechanism of hierarchical safety risk control and hidden danger investigation and management, eliminates all kinds of potential safety hazards in an all-round and multi-angle manner, and discovers, coordinates and solves blocking problems in a timely manner. The construction personnel continued to fight on the wall chart and vigorously carried out the "project to win the gold medal" labor competition, which created favorable conditions for the successful completion of the construction task.
It is understood that after the completion of the Jida Yuan high-speed railway, it will form a passenger corridor from Hohhot to Taiyuan via Datong, connecting the two urban agglomerations of Hubao-Eyu and the central basin of Shanxi, further connecting the Yangtze River Delta and communicating with Beijing-Tianjin-Hebei, making personnel exchanges more convenient, resource flow smoother, and continuously promoting high-quality regional economic and social development. (Source: Beiqing Net)
06
The TJ-6 Biaochisong Tunnel of the Jilin section of the Shenyang-Baihe high-speed railway was successfully completed
At 8:58 on July 5, the TJ-6 Biaochisong Tunnel in the Jilin section of the Shenyang-Baihe high-speed railway was successfully completed. Following the breakthrough of the Heisonggu Tunnel, the construction of the tunnel project of this tender section has achieved "two continuity", marking a new breakthrough in the construction of the project and laying a solid foundation for the construction of the pilot section of the track project.
The Chisong Tunnel of Shenyang-Bai High-speed Railway is located in Wangou Town, Jiangyuan District, Baishan City, Jilin Province, and is a single-hole double-line tunnel with a total length of 1553 meters. The entrance and exit of the tunnel are equipped with beveled cushioned tunnel doors, which are connected to the Wangou Bridge and the National Highway 201 Bridge respectively. The maximum depth of the tunnel is about 100 meters, and the construction is carried out by one-way boring at the exit end.
The tunnel is located in the hills of Changbai Mountain and low to medium and low mountainous areas, sandwiched by ravines and valleys, with lush vegetation on the surface. The whole tunnel is freeze-resistant and fortified, and the tunnel entrances and exits are all abnormal sections such as shallow burial, bias pressure, fault zone, etc., passing through one fault, two class I abnormal areas of rock mass fragmentation, and six class II abnormal areas, with a maximum daily water inflow of 6287 cubic meters. Andesite, sandstone, shale, rock quality changes frequently, resulting in many changes in surrounding rock grade, many lining types, and many construction method conversions.
In order to build quality engineering, since the start of construction, the Shenyang-Baizhou high-speed railway project department has optimized the construction plan for many times in view of many difficulties such as water-rich areas of tunnels, soft rock deformation, and non-integration of contact zones, improved various emergency plans, and continuously optimized resource allocation. The construction personnel are equipped with hydraulic inverted arch trestle bridge, information intelligent lining trolley, 3D scanner and other advanced tooling equipment, using the three-step method and the step method for construction, and applying a number of advanced geological forecasting methods in the mode of "short, tight, fast and diligent" to comprehensively explore the surrounding rock situation in front of them, ensure that the construction method is dynamically adjusted and the tunnel drainage prevention construction in alpine areas meets the standards. They also implemented the three-level safety education, strictly abided by the operating procedures, achieved the set goals of safety and controllability, stable quality and smooth penetration, and won valuable time for the follow-up construction of the arch of the subsequent tunnel, the follow-up construction of the second liner and the speeding up of the construction of ancillary projects such as the trench cable trough. (Source: China Jilin Net)