Hefei, known as Luzhou in ancient times, is the bright center of Wanjiang city belt. Now, with the brick and tile of the ancient city wall, the builders of Hefei subway are riding horses to create greater glories. "Take a step back and ride with the whip, and xiaoyaojin will fly to Yulong." The sections from Yulan Avenue Station to Tianzhu Road Station and Tianzhu Road Station to Science Avenue Station of Hefei Metro Line 2, which were built by China Railway Shanghai Engineering Bureau Group, are located on the main traffic lines, with a total length of 3,640.9 m and a construction period of 9 12 days. It is expected to be completed on February 9, 2065, 438+06. After completion, the east-west connection of Hefei downtown will be realized.
From February to July this year, the shield section of TJ09 section of Hefei Metro Line 2 won the first place in the comprehensive evaluation of Hefei urban rail transit project for six consecutive months. Up to now, * * * has won the first prize for six times and the second prize for two times, and has become the "leader" of the whole city 14 bid evaluation section. How are the six firsts of TJ09 section project tempered? All these are attributed to the five "essences" of all-round project management.
On-site Excellence leads the trend
Walking into the construction site of TJ09 shield section, you are greeted with neat planning and civilized construction. The project implements the 24-hour leadership duty system and the on-site guard system. The main leaders set an example. Xu Tao, the project manager, spent several hours on the construction site, climbed the gantry crane, checked the equipment and consistency, and controlled the quality and safety of the site in real time. In case of major risk sources and construction nodes, the leading group is on standby around the clock to ensure that the first person responsible for on-site construction is always supervised. The site station adopts 24-hour seamless handover, mainly focusing on four aspects: segment assembly quality, bolt re-tightening, civilized construction and shield tunneling posture. Technicians from the engineering department go to the site to check the civilized construction at least twice a day, record the shield tunneling parameters in real time, and write the data into the office.
The construction site of TJ09 Bid Section is located on the main road, with large traffic flow and serious dust pollution. The leading team led the technicians to sprinkle water on the site actively to reduce dust, protect the construction environment on site, and make the site meet the dust-proof and pollution-proof standards of Hefei Municipal Government. The excavation of Hefei project is a "long-standing problem". According to government regulations, it is strictly forbidden to dig in the college entrance examination, festivals, rain and snow and other seasons. In this year's flood season, there was a rare continuous rainfall of more than 40 days, and it was difficult to dig the soil field, which seriously affected the construction progress. The Hefei project made a heavy attack, replacing the unearthed team and monitoring the traffic and weather conditions in real time. The unearthed quantity increased from the original 30 vehicles/day to the highest 120 vehicles/day. The excavation efficiency has been improved by a full 3-4 times. In rainy and snowy weather, the project personnel spread colored strips of cloth on the main road of the soil yard in advance to prevent the soil yard from being soaked by water, and it can be unearthed directly the next day when the rain stops, which speeds up the work.
In February this year, Zhang Qingjun, Mayor of Hefei, visited the TJ09 section of Hefei Metro Line 2, inspected the shield construction area and the first-line construction site, affirmed the construction quality and safety monitoring on site, and asked all units under construction to do a good job in process control and continue to build Hefei Metro with high speed, strict requirements and high standards.
Plan, carefully arrange, optimize and change the scheme.
Because the TJ09 and TJ05 sections of Hefei Metro Line 2 are two sections of the same team, the leading bodies and technicians often run at both ends of the 9 th section and the 5 th section, which has a heavy workload and insufficient experience. Xu Tao, the project manager, stipulated that every employee should make a list of responsibilities, adopt the work output system to clarify the division of responsibilities, and technicians should strictly abide by the three inspection systems. Each technician should take turns at the end of the study, and be familiar with the scheme, measurement, side station and other work. , and gradually realize the "one expert and many functions" to ensure the orderly operation of the two standards.
At his request, the surveyors will recheck the monthly measurement, and measure the segment and shield posture twice a day. At the same time, the advanced VMT measurement technology is adopted on the shield machine, and the combination of electronic measurement and manual measurement ensures the accuracy of data during shield tunneling.
Experts from the expert database of Hefei Rail Transit Quality Supervision Station are invited to review the construction scheme of major hazard nodes of Hefei Project, and the construction technical scheme is optimized and changed according to the opinions of experts. Aiming at the two major construction difficulties of crossing the viaduct on the west Yangtze River Road and crossing several commercial squares, a large number of surveys and investigations were carried out on the buildings along the line in the early stage of the project. When crossing the foundation of the viaduct on the west Yangtze River Road, we should actively slow down the propulsion speed and control the parameters such as speed, thrust, torque and posture of the shield machine. At the same time, the land subsidence is monitored in real time by using information technology to ensure the success of crossing. When crossing Shang Hui Square, technicians investigated the specifications and models of the anchor cable in the underground garage, changed the original design, and pulled out the anchor cable before the shield arrived to prevent the safety risk of crossing.
Cost careful calculation, refinement, tapping potential and increasing efficiency
The newly added design changes not only improve the quality and safety, but also bring potential for the project to dig for change claims. After communicating the cost with the owner, the project will generate more than 500,000 yuan in income and profits. As early as the initial stage of end well reinforcement between Yulan Avenue Station and Tianzhu Road Station, the project optimized and changed the construction scheme of three-axis mixing pile combined with horizontal grouting and jet grouting pile, saving more than 200,000 yuan.
The project fully implements the concept of refined management, and the bidding and procurement of materials adopts the combination of centralized procurement and independent procurement, and saves costs in an all-round way based on the principle of price advantage. Due to the low centralized purchasing price of segment bolt group company, the unit price of segment bolt is 20.2 yuan, resulting in a profit of more than 200 thousand yuan. Outbound earthwork adopts independent bidding, and the bidding price is the lowest across the board, saving 360,000 yuan. The price of foaming agent independently purchased by the project is lower than the company's responsibility cost price of 654.38+10,000 yuan per ton. Realize the surplus of 1.300 yuan by saving consumption. When Baihuan accepted the project, the best mixture ratio and parameters of grouting were found through experiments, and the actual dosage was less than the theoretical dosage. After many inquiries, all grouting materials are lower than the company's responsibility cost, saving more than 520 thousand yuan.
"Budget before work, accounting at work, and calculation while doing." Xu Tao, the project manager, publicizes the importance of responsibility cost management to employees and sets up the economic consciousness of all employees. Not only through the company's centralized procurement, online procurement, supplier negotiations and other ways to "shop around." However, we also strictly control unproductive expenses, implement the accountability system, and do a good job in cost management through careful calculation.
Careful maintenance of equipment, professional independent maintenance.
The project has set up a professional shield maintenance team, and innovatively adopted the mode of promotion, maintenance and rectification to maintain large-scale equipment such as shield machines at the peak of tunneling. In the process of shield propulsion, the mortar falling from the oil cylinder is easy to wear. After discovering the situation, the criminal master with 10 years of shield maintenance experience led the team to maintain the key links of the shield machine, such as tunneling, sealing, splicing and grease, which effectively reduced the failure rate of the shield machine and fully ensured the propulsion efficiency.
Hefei project fully responds to the call of the newly issued "Appraisal Method of Red Flag Shield Machine", gives full play to the advantages of specialized shield technology, and minimizes the shield propulsion loss through maintenance. In the past, the cost of shield maintenance subcontracting company was as high as more than 3 million yuan, and the sudden failure could not be repaired in time, which hindered the progress of the construction period. At present, the independent professional shield maintenance mode of promotion, maintenance and rectification, operators and maintenance personnel prevent and deal with faults in advance, saving a lot of maintenance costs for the company.
Implement the characteristic party building culture steadily and meticulously.
The quality and efficiency of shield propulsion can not be separated from the escort of on-site safety activities. The project gradually expands the safety responsibility system and establishes a real-time safety management network. Full-time safety officers, group safety officers and Qing 'an Gang go deep into the "zero dead angle" of front-line supervision every day, report potential safety hazards online and expose them on the safety and quality exposure platform. Up to now this year, * * * has found and rectified 225 potential safety hazards and exposed 526 safety and quality information. In addition, weekly safety inspection, special inspection of inflammable and explosive articles, flood control drills and other forms are readily available, which comprehensively regulate the on-site construction behavior.
"Construction grasps the scene and enters the market to grasp education." Since the start of the project, we have regularly organized safety production study and training every month, organized three-level education for new employees 143 person-times, conducted 72 person-times monthly safety training for part-time safety managers and 36 person-times safety education for special types of work, realizing "full coverage" of safety education. This year, since the company launched the "safety lecture" for all employees, the project has conducted the "safety lecture" 19 times and trained 536 people. Leaders and department heads go to the lecture hall to talk about personal experience and teach professional knowledge, so that the safety education of all staff can be "in-depth".
Ming, the project secretary, took the lead in organizing "Shield Challenge" and swearing-in activities, and carried out characteristic party building activities closely around construction production, giving full play to the backbone and demonstration role of party member, a key position, to realize "no accidents around party member". Party and government leaders took the lead in implementing "endorsement by signature" and implementing target responsibility management at different levels. A total of 34 copies of "Safety Production Target Responsibility Letter" 134 were signed at different levels, and the safety responsibility was divided into higher and lower levels. The Party branch was "very attentive" in providing political guarantee for safety production.
Yu Longfei, Luzhou City, casts a monument at the foot of Shushan Mountain. For more than a year, the TJ09 bid section project of Hefei Metro Line 2 has been praised as "Excellent Project Department of Line 2" because of its persistence in quality, safety and management system, and the owner "sees it in his eyes and keeps it in his heart". TJ09 Bid Section Project is based on specialty, polishing the "new brand" of shield machine, focusing on accuracy, establishing a "new mode" of management, creating a quality project that owners trust and citizens feel at ease, and opening up a "new world" of Hefei rail transit market.