Qingdao on the track continues to expand. Soon after the official opening of the first phase of Metro Line 6, there was good news from the west extension of Metro Line 2. On May 15, with the completion of the welding of the last rail joint between the international cruise home port station and Taishan Road Station, the Qingdao Municipal Public Works Quality and Safety Supervision Station, the construction management of the first construction branch of Qingdao Metro Group, and the first phase of the Qingdao Metro Line 2 project adjustment plan "Sichuan Road (Ferry) Station-Taishan Road Station Section" (referred to as the "West Extension Section of Line 2") undertaken by the 11th Bureau of China Railway were fully opened, creating favorable conditions for the comprehensive development of subsequent power supply, communication, signal and other operations, and making every effort to open at the end of the year.
More than 30 meters underground, the reporter of this newspaper investigated the scene of the rail opening of the west extension section of Line 2.
Smarter ▶▶▶
Smart construction site "at a glance"
On the morning of the 15th, the reporter walked into the project department of the track-laying base of the ferry station and saw the huge electronic screen displaying the pictures and data from the inside and outside of the tunnel, the operation site, and the deployment of personnel in real time. "Big data and artificial intelligence technology have been well applied in engineering." Tian Fuxiang, chief engineer of the track-laying professional project, told reporters that after adopting the intelligent dispatching system in the track area, the on-site construction situation can be seen through the large screen or mobile phone, and the personnel and equipment, construction progress, and material reserves are clear at a glance, which greatly improves the on-site construction progress. In order to ensure the efficiency and construction safety of the track-laying operation of the west extension section of Line 2, the intelligent dispatching system of the rail area of Qingdao Metro No. 1 Construction Branch adopts advanced communication technology, and realizes the real-time transmission of video images in the track area through the installation of video surveillance throughout the whole process, and the personnel positioning and network signals cover all underground lines, so as to realize voice intercom, real-time positioning and real-time video transmission in the tunnel, ensure the safety of driving and operators, and realize the remote synchronous management of "site + background". "Every 500 meters, we set up two monitoring probes to transmit the images in real time." Tian Fuxiang said that managers can view, command and manage on-site construction in real time through mobile phones or monitoring centers, which has the advantages of remoteness, intelligence and automation. The system is like a "smart brain", which helps managers understand the on-site production situation and safety management in real time, and carries out intelligent and visual dispatching and command of project personnel organization, material operation, vehicle scheduling and other aspects through efficient information transmission, which greatly guarantees the construction organization and scheduling of various specialties of the underground line and the safety management of the track area, and greatly improves the management level of the track area and the efficiency of track laying construction. In addition, the safety helmets worn by on-site workers also contain "high technology": the safety helmet has a built-in chip, which can realize the accurate positioning of personnel and effectively ensure the safety of construction operations.
More accurate ▶▶▶
Track laying error is controlled within "millimeters"
Track is one of the core technologies to ensure the safe, stable and smooth operation of high-speed trains, in the process of track laying, in order to ensure a good track geometry, it is necessary to adjust the track row to the design position one by one, which is a finer than embroidery "kung fu". The track-laying accuracy of the western extension of Line 2 has reached the millimeter level. "The first time is coarse adjustment, the second time is fine adjustment, the purpose of multiple track adjustment is to control the error of track geometry within the range of 1 millimeter, so as to ensure that the subway train is smooth and comfortable in the running process." Construction technician Han Lei said.
The track-laying construction of the west extension section of Line 2 adopts the domestic advanced subway track-laying measurement CPIII. track control network precision measurement technology, which changes the original manual track adjustment method with the base gauge ruler, realizes the track geometric size control equipment, and the track fine adjustment operation is fast and accurate, and the track state can be comprehensively and systematically measured, analyzed and adjusted.
Construction crews are laying tracks.
After the rail is welded, it is necessary to carry out normalizing operation to eliminate stress, refine the metal crystal structure, and improve the quality of the weld. The operation of the west extension section of Line 2 adopts intelligent induction electric normalizing equipment, abandons the traditional heating method of oxygen and acetylene combustion, uses its own generator set for power supply, and conducts induction heating normalizing on the rail welded joints by electromagnetic induction, which overcomes the quality problems and uneven heating caused by improper manual operation of the traditional flame normalizing, and the welding quality is greatly guaranteed, and the construction safety has been substantially improved.
Quieter ▶▶▶
Vibration-damping "mattress" on the rail sleeper
The western extension of Line 2 is located in a densely populated area of Qingdao's old city, passing through schools, residential areas, the new crown viaduct, Jiaoji Railway, Jinmao Bay business district, etc. In order to reduce the impact on the line, four types of track beds are set up on the track of the west extension section of Line 2, namely general vibration damping track bed, medium vibration reduction track bed, high vibration reduction track bed and steel spring floating plate track bed. Among them, the high-level damping track bed and the steel spring floating plate track bed account for about 40% of the track-laying tasks. In order to reduce the impact of the ground vibration generated by the train during operation, the track adopts the domestic leading steel spring floating plate vibration damping track bed, and the spring device is added to the overall track bed, just like making the track sleeper on the "mattress", which can reduce the vibration by more than 15 decibels, making the train more quiet underground.
Liu Dongbo, the person in charge of the track project of the first phase of the adjustment plan of Qingdao Metro Line 2 of China Railway 11th Bureau, said that since the start of track laying, the project department has made full use of the track area dispatching system to improve the effective utilization rate and construction safety of the track area; By optimizing the track-laying gantry span process, the time in and out of the station is shortened, and the effective construction time is improved. Through the use of intelligent induction electric normalizing equipment, the quality and construction safety of rail joints are improved.
More efficient ▶▶▶
"In the snail shell" set a record
The track-laying construction of the west extension of Line 2 is jokingly called "a dojo in a snail shell": there is only one track-laying base at the ferry station and the site is narrow, and all track-laying materials and machinery can only be lifted in and out from a rail row shaft with a span of 30 meters, and the rail row shaft with a depth of 40 meters is still oblique. However, under such construction conditions, it took only 56 days from March 21 to May 15, and the daily track laying of a single operation surface reached 125 meters, setting a new record for Qingdao Metro track laying in a single day. During this period, the "golden key" of project management played a vital role in team construction. The No. 1 Construction Branch of Metro adheres to the guidance of party building, mass line, and participatory democratic management, and activates the "minimum cell" and "maximum vitality" of the front line of the team: through small legislation to stimulate the enthusiasm of the team, the construction of ordinary track bed has been increased from 85 meters per day to 125 meters per day, and the construction of steel spring floating plate has been increased from 50 meters per day to 75 meters per day, setting a new record for track laying in a single day; For the installation of the three-track base for power supply, the team members optimized the operation mode, embedded a pouring molding in advance, greatly reduced the follow-up work of power supply, improved the quality of hole molding, and achieved good results with zero damage to the track bed. In view of the long time of the track-laying crane passing through the station, Chen Hongjun, the leader of the track-laying team, proposed a new method of changing the span of the track-laying crane, and the team and the "two-in" personnel conducted in-depth research and adopted a gradual change method to shorten the span time from 10 hours to 7 hours.
The west extension section of Line 2 is 3.84 kilometers long, starting from the turnaround line of Sichuan Road (Ferry) Station in Shinan District, and connecting with the existing Metro Line 2 through Taishan Road Station to the east, including three stations and four sections. After the opening, the interchange with the 4 lines will help the international cruise port area, small port, ferry and other areas to break through the traffic barrier of the Jiaoji Railway and the new crown elevated road, drive the old city in the west to access the rapid public transportation corridor, effectively improve the quality of regional development, enhance the development level, and promote the integrated development of Qingdao's "port area, park and urban area" to a new level.
Trend map of the western extension of Line 2.
Zhang Liang, the representative of the track engineering industry of the first construction branch of Qingdao Metro Group, said that at present, the civil engineering has entered the final stage, the mechanical and electrical engineering construction task has passed half, and the decoration has been fully entered. After the rail is opened, we will continue to promote key nodes such as electric communication and communication communication of the whole line, and carry out dynamic joint commissioning work. In the follow-up construction, we will continue to focus on team construction to promote the early completion and opening of the western extension of Line 2 with high quality and efficiency.
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Funing Interchange Station of Line 5 ushered in the first auxiliary entrance between it and the main station
The No. 1 safety entrance/No. B entrance and exit of Funing Interchange Station of Metro Line 5 and the main station have been successfully connected recently, and the construction of the project has made phased progress. Funing Interchange Station is a two-storey underground island underground excavation station, with a total length of 214 meters and a standard section width of 21 meters, which is constructed by the Third Construction Branch of Qingdao Metro Group Co., Ltd. and constructed by China Railway 12th Bureau Group Co., Ltd. During the construction process, the project department maintained the expected goal of "zero accidents" in construction and production, and completed the excavation of the No. 1 safety entrance/No. B entrance and exit cross passage 3 months ahead of the planned construction period, becoming the first auxiliary entrance between Funing Interchange Station and the main station.
Guanhai News/Qingdao Evening News/Pocket Qingdao Reporter Xu Meizhong