Station 24： Entering Xuzhou Metro Line 1 Project-State-owned Assets Supervision and Administration Commission of the State Council

Rendering of Xuzhou East Station of Xuzhou Metro Line 1

On September 27th, the 40-year-old architectural miracle tour of China-China Construction Open Day: the 24th stop of the large-scale brand communication campaign entered Xuzhou, the central city of Huaihai Economic Zone, and held the activity of "Building Xuzhou and Witness Development", which unveiled the mystery of the innovation and development of China Construction Group Co., Ltd. (hereinafter referred to as China Construction) in the field of rail transit construction to the public and the media. The event was held at Xi ‘an Road Station of Xuzhou Urban Rail Transit Line 1. About 120 teachers and students from China University of Mining and Technology, Jiangsu Normal University, xuzhou institute of technology and other well-known universities in Jiangsu Province, as well as more than 20 media outlets including Xinhuanet, Economic Daily, China Jiangsu Network, Xinhua Daily, Xuzhou TV Station and Xuzhou Daily came to witness the event.

The activity comprehensively introduced the development history and achievements of China architecture in recent years in the form of promotional videos, exhibition boards and on-site explanations, focusing on the achievements of China architecture in implementing the national development strategy and fulfilling the responsibility of central enterprises. Participants watched the China architectural image film, the theme film "Miracle of Building a Certificate", the promotional film "Miracle of Building a Certificate in China" and "Dream of Building a Central City in Huaihai for 40 Years", and learned about the struggle of China architecture in inheriting red genes, condensing blue power and promoting green development in the past 40 years of reform and opening up. Participants also visited the track section between East Square Station and Xi ‘an Road Station of Xuzhou Metro Line 1 to learn about the whole process of Xuzhou metro construction.

Through dialogue and question-and-answer, the process and story of China Architecture’s all-round participation in Xuzhou’s real estate, expressway, airport, rail transit, municipal highway, utility tunnel, environmental management and other fields from 1978 to 2018 were told, which helped to break the development problems, improve urban comprehensive transportation, enhance the living environment, raise the height of the city, activate the local economy and promote the high-quality development of Xuzhou.

Join in the upsurge of infrastructure construction, and cut through difficulties in the field of rail transit construction at home and abroad

In recent years, China’s architecture has closely followed the national strategies such as "Beijing-Tianjin-Hebei coordinated development", "Yangtze River Economic Belt" and "Belt and Road", and its infrastructure has developed by leaps and bounds, covering almost all infrastructure fields such as high-speed railway, rail transit, expressway, tunnel and bridge, airport station building, energy and nuclear power, municipal pipe network and hydraulic port. In the field of subway investment and construction, China has successfully transformed its architecture, and invested in the construction of several subway lines in many countries and regions, with a total mileage of hundreds of kilometers. Among them, it includes the representative work of the Belt and Road Initiative, the first light rail project in Kazakhstan-the No.02 contract section of Astana Light Rail Phase I project, the above-ground steel structure project of Dubai Metro Station (Green Line) project, the subway tunnel project of Bange Extension Line of Singapore Land Transport Administration, and other overseas rail transit projects; The subway lines invested and built in China are all over the country, serving thousands of households, including Shenzhen Metro Line 9, Shenzhen Metro Line 13, Nanning Metro Line 2, Xuzhou Metro Line 1, Xuzhou Metro Line 3, Zhengzhou Metro Line 3, Qingdao Metro Line 8, Chengdu Metro Line 11, Chongqing Metro Line 9 and Dalian Metro Line 4, and undertaking the construction of more than 40 subway blocks in more than 30 key cities across the country. The overall scale is over 500 billion.

Keep up with the times and guide the first subway invested and built in PPP mode in China

In order to adapt to the characteristics of large investment, high risk, long cycle and high cost in subway construction, and solve the complex contradiction that local finance is not enough to support subway construction, but urban development is in urgent need of subway construction, China Architecture takes the lead in adopting innovative modes such as PPP (government and social capital cooperation mode) to actively participate in the investment and construction of national infrastructure. This model was first applied in Xuzhou Metro Line 1. Entrusted by Xuzhou Municipal People’s Government, Xuzhou Rail Company and China Construction Co., Ltd. jointly established a project company. The two parties jointly completed the capital contribution according to about the proportion, and the remaining funds were raised by the two parties through bank mortgage, etc. In the financing scheme of the project, equity financing, trust and asset management plans were comprehensively used, and the sources of funds included their own funds, insurance funds and bank funds. This model can effectively make up for the lack of financial investment in the current period, reduce the pressure of financial expenditure in the current period, smooth the fluctuation of financial expenditure between years, prevent and resolve the risk of government debt, and also turn the disadvantage of large capital demand into the advantage of strong capital liquidity, realize the "financial integration to incite large projects", ensure the smooth landing of projects, and have the effect of four or two. At present, it has also been included in the first batch of 30 PPP pilot projects in China and has become a demonstration project of PPP cooperation in national rail transit construction.

Smart construction breaks the construction problem of Pengcheng Square Station.

Pengcheng Square Station of Xuzhou Metro Line 1 is located in the most prosperous commercial center of Xuzhou City. It is the interchange station of Xuzhou Metro Lines 1 and 2, and it is also the first large-scale interchange station integrating open-underground-cover-excavation in China. The station is super-large, with the deepest foundation pit of 34m, 17 entrances and exits, 3 groups of wind pavilions and 2 sinking squares. The foundation pit of Line 1 is 141.55m long and 58.5m wide, and the designed depth of the foundation pit can reach 35.5m. It is the largest foundation pit in the field of subway construction at present, and the distance between the diaphragm wall of the subway project and the nearest retaining pile of Suning Plaza, the tallest building in northern Jiangsu Province, is only 0.9m, which is not allowed to be lost. Because of the sensitivity of its surrounding environment, the prominence of geological problems and the complexity of structural construction, it has been rated as the most difficult in Jiangsu and rare in China by industry experts.

In order to overcome the construction problems under siege and ensure the progress of the project as scheduled, the project department fully realized the risk points and difficulties of the project by means of expert guarantee mechanism, training and expert consultation, and invited experts such as Wang Mengshu, academician of China Academy of Engineering, former chief engineer of Guangzhou Metro and former chief engineer of Shenzhen Metro to make suggestions for Xuzhou Metro construction. At the same time, two international advanced improved versions of SR385RC8 rotary drilling rigs were introduced. Based on the original model, the power of the improved rotary drilling rigs was increased to 420KW, and the average drilling speed per hour was about 50cm~90cm, which greatly improved the slotting speed of underground diaphragm walls and temporary middle columns. The project department actively carried out key technical innovations, such as "open-dark-cover-excavation complex structural system transformation and its impact on sensitive environment, disaster-causing mechanism of soil-rock-water coupling under blasting vibration, and smart construction technology in the whole construction process based on BIM technology". In just four months, 56 diaphragm walls and 87 lattice columns were built, which successfully solved many problems such as lattice column underpinning, shield passing through the station, underground excavation chamber group construction, advanced detection and control of groundwater and so on.

BIM technology carries out intelligent management and control, reaching the international advanced level.

In the process of overcoming the construction problem of Pengcheng Square Station of Xuzhou Urban Rail Transit Line 1, the project established a research group on the application of BIM technology in the construction of subway station (Pengcheng Square Station) under complex conditions. Using the 3D modeling technology of BIM, complete and practical engineering information is added to it at the same time, making it an informationized 3D entity including design intention, project data, construction information, material information and design management data. From the initial model construction to the establishment, implementation and application of safety, quality, progress, monitoring and early warning, design management and other modules, through continuous exploration in the process, the current mobile phone, web and pad software system is formed, so that you can know and control the construction site situation anytime and anywhere and realize smart construction. At the construction site, every builder holds a mobile phone with BIM (Building Information Model) system APP in his hand. The whole project is decomposed into several models showing digital simulation status and distributed to each type of work, just like being in a "WeChat group", each node will be distributed at the first time and saved at the first time after completion. When the project is completed and accepted, the acceptance data will be presented in the form of hard disk data, which successfully solves the problem of underground excavation room. At present, four computer software systems, such as "smart construction Platform Android Mobile Phone Software System V1.0", have successfully passed the examination of China Copyright Protection Center.Obtained the computer software copyright registration certificate issued by the National Copyright Administration. The project "Research on the Application of BIM Technology in the Construction of Metro Station (Pengcheng Square Station) under Complex Conditions" has also been appraised as reaching the international advanced level by Jiangsu Provincial Housing and Construction Department and industry experts.

Independent research and development of 3 information construction platforms, and deep integration of smart construction concept into the front line of project construction.

During the construction of Xuzhou subway, the project has independently developed three information construction platforms through continuous exploration and accumulated experience in the construction practice. First, smart construction information platform of rail transit: deeply integrate BIM with project management logic to achieve process BIM, everyone BIM and smart BIM, and realize dynamic and intelligent control of the whole process through schedule-driven management of all elements. Second, the monitoring platform of shield construction: internet plus and big data analysis technology are adopted to realize real-time, all-round and intelligent monitoring of shield construction process and solve the management problems of shield construction of multi-project groups. Third, the platform of safety and wisdom education: adopting mobile internet technology to realize multi-learning module embedding, efficient online examination and intelligent statistical analysis. Realize the integration of "standard workflow, informatization of workflow, digitalization of information work and intelligence of data utilization".

Build a VR Safety Experience Hall to enrich the forms of safety education.

In terms of safety education, the first "VR Safety Experience Hall" was built in the construction of rail transit in Jiangsu Province in bid 05 of Xuzhou Urban Rail Transit Line 1. According to the actual situation of subway construction, the VR experiential safety education system has more than 20 kinds of experience items, such as falling from a height, object hitting, collapse, electric shock and mechanical injury, which integrates common accidents in the construction site with virtual technology, and establishes a "real" construction site in the VR world, which is convenient for better safety education for operators.

Start an underground railway war to ensure zero risk and accidents.

The geological conditions in Xuzhou are complex and diverse, and the construction of the whole shield section is extremely difficult, and the technical quality requirements are extremely high. The shield passes through 16 railways in xuzhou station, and the geological conditions in the area of nearly 200m are complex. The geological conditions in xuzhou station are all soft and hard. There is a 12-meter-thick clay layer at the top of the tunnel where the shield passes through the old Yellow River. Damalu Bridge is a stone pier. When the shield goes under, the rubble foundation is only 7.22 meters away from the top of the tunnel. Faced with many risk sources, the "Shield Commando Team" organized by the project took the initiative to attack, formulated a precise and rigorous construction plan, strictly controlled the tunneling parameters during the shield tunneling process, and carried out the first pressurized warehouse opening work in Xuzhou. Well-known shield experts in China were invited to organize safety consultation meetings to learn advanced shield construction experience in China. At the same time, the automatic monitoring information platform is introduced to provide first-hand information for shield tunneling, and through the analysis of the data, the parameters of shield tunneling are adjusted in time to ensure the safety and stability of shield tunneling under xuzhou station. It took only 76 days to complete the construction task originally planned for 4 months, and the original construction task was completed efficiently.

A big country is a heavy weapon, and a "hole-digging expert" shield machine cuts mountains and waters. Force value MAX

In the subway tunnel excavation, a kind of big guy who can dig holes underground is bound to be used. This is the shield machine specially used for tunnel excavation, which is often called underground pangolin figuratively. It is a big block weighing 450 tons, and consists of 12 parts, such as cutter head, front shield, middle shield, shield tail, assembler, screw machine, equipment bridge and backup trolley. The system is driven by hydraulic power, and uses 10kv high-voltage power distribution, which has the characteristics of high automation, labor saving, fast construction speed, one-step molding, no influence from climate and no influence on road traffic at the top of the tunnel. The shield machine of subway tunnel can eat soil in front and discharge soil behind, and it can dig 10 meters underground on average every day, which is 8 to 10 times higher than the efficiency of manual excavation. Shield machine runs like a train that can drill the ground, and its working principle is actually somewhat similar to that of an electric razor. When it starts to work, it pushes forward by the power given by the jack in the fuselage, and rotates the cutter head to dig up the soil layer. When excavating the soil layer, stick it firmly with concrete ring segments to prevent the soil layer from collapsing. Each time, one ring is 1.2 meters long and contains 6 segments. The excavated soil will be transported to the vehicle loaded with soil by the screw conveyor and transported back to the ground, and then the shield segments will be assembled in turn by the segment assembling machine, forming a tunnel prototype.

When the subway meets the protection of cultural relics, the "Tongheyu Silver" is translated throughout the building.

The former site of "Tongheyu Silver Bank" is one of the few buildings of the Republic of China in Xuzhou with western architectural features, and it is a municipal-level cultural relics protection unit. This building of the Republic of China witnessed the development history of Xuzhou financial institutions and the historical process of Xuzhou’s economic development. Because the building is located within the construction scope of the railway station of Metro Line 1 being built in our city, the project department is faced with the choice of demolition and reconstruction. If it is rebuilt in different places, although the cultural relics exist, the historical features will disappear. Through investigation and demonstration by the cultural relics department of Xuzhou City, and drawing lessons from foreign experience, the translation protection method is the only best choice, which can not only ensure the authenticity and integrity of the cultural relics protection unit, but also make the relocation work less and the time period shorter. The translation protection of the former site of Tongheyu Silver House is the first innovation in the protection method of immovable cultural relics in Xuzhou City. On-site use of three SPMT assembled automatic flatbed trucks to consign the translation building, with a total of 216 tires, can easily bear the weight of a three-story building of 1,300 tons. After the jacks supporting the building at the front of the car are slowly lowered, the whole building will fall on the orange jacks on the car body, which can automatically control the building to remain horizontal during the dragging process. Since the new address is located about 240 meters northwest of the current location, The space on the construction site is also limited, so the flatbed truck first drags the whole building for several tens of meters to the north, and then nearly 200 meters to the west. After two 90-degree turns, the whole process finally safely escorts the Silver House to the "new home". After the translation, the "Tongheyu Yinhao" building in Xuzhou will no longer be used for business.Protect the whole for citizens and tourists to visit.

Using intelligent monitoring system to realize intelligent management of construction site

The project has also innovated the new mode of "video monitoring+site supervision", with the help of "internet plus" in project management, deployed a remote monitoring network throughout the project, and made full use of effective means such as video monitoring and online monitoring to create a three-dimensional, full-coverage intelligent site supervision network, which has effectively controlled the project progress, safety and dust control.

The 49km underground silver dragon is vertical and horizontal, and the accuracy error is only 0.1 mm.

The track is often called the Silver Dragon that shuttles underground. This Silver Dragon moves around in underground space, passing through the complex environment such as elevated, open-cut and shield sections through small radius curves and vertical curves with large gradient, and finally reaching the goal of safe, comfortable and fast modern railway and urban track. The smoothness of the track directly affects the safety of passenger cars and the comfort of passengers. As a key specialty in the whole subway construction process, the track laying field of urban rail transit plays an important role in construction efficiency and quality. Xuzhou Metro Line 1 adopts the measurement technology of high-speed railway track control network, studies and establishes a new CP ⅲ track measurement basic control network for urban railway, develops a complete set of data acquisition, data analysis and processing software and supporting measurement tools for track precise positioning, establishes the track basic control network control points to be arranged on the segment, and arranges the platform eaves at the station. Real-time reflection of the track state through the prism of the track inspection trolley, and fine adjustment of the total station. After setting up the station freely, eight pairs of control points are jointly measured to locate the line alignment. The total station displays the deviation between the track geometric size state and the line alignment and slope adjustment through an external special computer, and fine adjustment is carried out through the deviation between the two. The error value of line ride comfort is controlled within ±0.1mm, which greatly reduces the subsequent operation and maintenance costs and improves the ride comfort.

The voltage of 34890V supports the day and night of the subway.

System mechatronics is the nerve, blood and brain of subway safe operation, and it is an essential and important component of subway safe operation. At the bottom of the tunnel, the ring network cable is neatly placed on the bracket, and the current needed for the safe operation of all subway equipment is always transmitted in the cable. Without it, the world of subway would be dark. In the upper part of the tunnel, the catenary is quietly suspended above the electric bus. After strict measurement and calculation of the pull-out value of the lead height, it ensures close contact with the pantograph of the electric bus and provides a continuous current for the driving of the electric bus. In the centralized interlocking area, the signal equipment flashes traffic lights alternately, and different logical relationships are calculated to ensure the safe operation of the subway. The multimedia equipment, time telling equipment and mobile phones of passengers and staff put in the train are all guarded by system electromechanical devices. From the flexible catenary of parking lot and depot to the rigid catenary of tunnel section, from traction hybrid substation to follower station, from centralized interlocking area to non-interlocking area, from section to station, the voltage of 35kV to 110V, 34,890 V makes the subway understand the darkness at night.

The maker of subway technical standards and the industry leader

On the one hand, it is a hard construction practice, and on the other hand, it is a detailed theoretical summary. During the construction process, the technicians of Xuzhou Metro Line 1 rely on scientific research topics and demonstration projects, and the project has successively compiled a series of technical guides for subway construction, such as the Implementation Guide for Quality Acceptance Data of Urban Rail Transit Engineering, the Management Manual for Quality Standardization of Xuzhou Rail Transit Engineering, and the Operation Guide for Xuzhou Rail Transit Engineering. China Architecture has become the construction standard setter and industry leader in the field of rail transit.

Overcome the problem of multi-discipline cross-construction, and make great achievements in innovative science and technology.

Xuzhou Metro Line 1 covers civil engineering, track laying, system electromechanical, conventional electromechanical, weak current, decoration and other professions. There are about 30 kinds of pipelines in each subway station, covering more than 10 professions, and the total length of pipelines is tens of thousands of meters. During the installation of electromechanical equipment, Xuzhou Metro Line 1 project pays special attention to the application of BIM building information model technology to realize the establishment of three-dimensional models of buildings, pipelines and equipment layout in the subway. The simulation technology is adopted to reflect the real information in the subway electromechanical system, so as to form feedback and interaction among various components, avoid automatic inspection and collision of various construction problems, make the pipelines reasonably arranged in a relatively narrow subway space, effectively overcome the problems of insufficient subway construction space, centralized construction and complex pipeline laying, and at the same time effectively control and manage the construction progress and cost in the subway electromechanical system. The project has also formed a series of scientific and technological achievements in view of the complex geological conditions: 4 scientific research projects have been successfully declared, 20 demonstration projects and standardized construction sites have been established, 36 patents, 17 construction methods, 11 QC achievements, 4 software copyrights, more than 40 papers published and 5 leading scientific and technological achievements compiled, and the construction practice has been successfully transformed into scientific and technological achievements that can be popularized and copied.

Make the construction enclosure into a civilized propaganda landscape

In the design of the construction enclosure, the project combined with the local historical and cultural characteristics, through full communication with the citizens, refined the symbols of the unique historical and cultural elements of the city, and carried out "school-enterprise cooperation", and entrusted the Academy of Fine Arts of Jiangsu Normal University and the School of Art and Design of China University of Mining and Technology to creatively complete the construction enclosure scheme. The design content is divided into seven colors: red, orange, yellow, green, cyan, blue and purple. The perspective block structure is used to decorate the photos of representative historical and cultural attractions and highlight the sectional renderings of the corresponding sites. The elements used are orderly and internally unified. The overall tone of the scheme is modern and atmospheric, which can reflect the characteristics of Xuzhou’s historical and cultural city and rail transit engineering, and achieve better coordination and integration with the surrounding background environment. The contents of the enclosure are presented in strict accordance with the "2+1" model, that is, two subway construction publicity and one public welfare cultural publicity. Among the 60 enclosures on Line 1 and Line 2, public welfare cultural propaganda accounts for one third. The content covers the slogan of the subway, the promotion of China’s traditional history and culture and core values, etc. No commercial advertisements are allowed. All kinds of public service slogans are catchy and deeply rooted in people’s hearts, which fully embodies the connotation of spiritual civilization in Xuzhou.

Create a provincial-level demonstration site for clean government construction and escort the project construction.

In order to create a "high-quality project with excellent cadres", the project, together with the Xuzhou Municipal Commission for Discipline Inspection and Procuratorate, jointly launched the "Striving for a Clean and Honest Culture Demonstration Site and Building a Sunshine Project with Inspection Enterprises" to further promote the construction of a clean and honest culture and build the first clean and honest culture room in the system as a warning base for clean and honest education across the project. The project also produced a series of incorruptible products with the characteristics of East China Company, such as incorruptible small fans, incorruptible desk labels and incorruptible manuals for party member, opened a column of incorruptible education on WeChat platform, pushed incorruptible articles, and regularly carried out incorruptible party education; The video monitoring system is used to supervise the bidding places in real time, which ensures that the bidding work is carried out in the sun, and effectively integrates the measures and means of building a clean and honest culture into daily life. Through scientific planning, multi-party linkage, cultural guidance and system guarantee, the company has given full play to the basic role of regional companies in spreading the culture of clean government, successfully established provincial-level demonstration sites of clean government culture, and provided a strong ideological guarantee for the implementation of infrastructure projects and market development. Zhongjian Huadong Company, which belongs to the project, has been evaluated by Xuzhou City and Jiangsu Province as a demonstration site for the construction of clean government culture at the municipal and provincial levels. Became the first unit in the China Construction System to obtain a provincial-level demonstration site for clean government culture construction.

Hand-painted engineering drawings of subway experts became popular and sought after by the Internet.

In the process of subway construction, there was an old man who became popular with professional, meticulous and accurate "hand-drawn engineering drawings", so that people who don’t understand engineering can also understand the general process of subway tunnel construction through these hand-drawn pictures. Zhang Jiashi, a subway expert who is nearly eighty years old, is a special expert in Pengcheng Square Station of Xuzhou Metro Line 1. He goes deep into the foundation pit tunnel of Pengcheng Square Station of Xuzhou Metro Line 1 during the day, and always takes photos with his mobile phone to record the situation of underground excavation. After work, he records what he saw and heard at the construction site during the day and shows it in the form of cartoons, showing the scene of "shocking and grounded" Xuzhou subway construction, so as to teach future builders the "18-character mouth" of underground excavation.

[Editor: Yao Teng]