On April 16, the first 3.5m shield tunnel constructed by the 3.5m shield method north of the Yangtze River - the "Binhai Star" shield machine of the Tianjin Binhai Rainwater and Sewage Diversion Reconstruction Project broke through the 2,000 ring mark. The "Binhai Star" shield machine is customized based on the characteristics of the project, with a cutterhead diameter of 3.74m and a total length of 142m, which is the first EPB shield machine used for rainwater tunnel construction in Tianjin.
The rainwater and sewage diversion project in Binhai New Area is one of the important projects of "building a beautiful Bincheng and creating a livable environment in Tanggu". The total length of the shield section is 3422m (2851 rings), the minimum curve radius is 150m, and the passing soil layer is mainly silty clay, and the burial depth is shallow, so it is difficult to control the ground subsidence. The section is laid along the Jintang Highway, and the environment along the route is extremely complex, with large road traffic flow and intricate underground pipelines. The project was undertaken by China Railway Tunnel Bureau.
Since the start of the shield, it has successfully crossed the Jinbin Light Rail Line 9, Jinbin Expressway subgrade, DN500 high-pressure gas, DN600 high-pressure gas and other risk sources, leaving only the shield to receive a large risk source, the shield construction progress, quality, civilized construction level continues to improve, and is currently tunneling forward at an average speed of 15-19 rings per day.
During the construction process, the construction personnel carefully organized the construction with the overall idea of strictly implementing the construction plan, optimizing resource allocation, strengthening equipment maintenance management, scientifically and dynamically adjusting parameters, strictly controlling the assembly and grouting process, and strengthening risk emergency management. Surface inspection system and daily meeting system; Strictly implement the special construction plan, one ring and one disclosure, one ring and one research and judgment, through the reasonable setting of soil silo pressure, strict grouting management, control the shield attitude, and effectively inhibit the settlement of shield construction; strictly implement the pre-construction plan disclosure and safety technology disclosure, and organize all management personnel and operators to make the disclosure before passing through the risk, so that all personnel can understand the risk characteristics and process control points; strengthen the construction monitoring and measurement management, conduct monitoring data collection twice a day, scientifically and dynamically adjust the construction parameters according to the monitoring results, ensure the measurement accuracy, and regularly review the attitude of the segments; and do a good job in the management of materials and equipmentReasonably arrange the procurement of materials, strengthen the daily maintenance of equipment, and avoid the occurrence of shutdown and waiting for materials.
In the next step, the project department will closely follow the node construction period, strictly grasp the safety and quality, do a good job in the connection of construction processes, further improve the tunneling speed, and ensure the smooth breakthrough of the section according to the node goal.
Report: Correspondent Wang Gang
Source: Yan Zhao Times