Create "Zhejiang's deepest place"! Sany SAC4000T7 left a footprint

The first phase of the S2 line of Wenzhou Municipal Railway has a total length of 63.63 kilometers and a total of 20 stations, which is a key construction project in Zhejiang Province. Among them, the SG5 standard is the most difficult control project, and the Oujiang North Mouth Cross-River Tunnel is the most difficult.

SG5 is the longest and deepest submarine tunnel in Zhejiang, with a total length of 2,664 meters, the deepest depth is 60 meters from the river surface, the depth is equivalent to 19 floors high, and the construction of 14.9 meters of super-large diameter shield is adopted.

The process of shield crossing is full of difficulties and huge risks. Due to the geographical characteristics of soft soil geology and rich biogas in the Oujiang estuary area,The construction of the project faced challenges such as biogas, silt, soft and hard composite strata, as well as ultra-shallow soil overburden construction, wind and rain resistance through the embankment, long-distance crossing of strong tidal sea waters, and crossing complex biogas areas.

Project leader Li Changyan introduced: "Working on such complex soil is like digging an intact hole in the tofu, and the difficulty can be imagined。 In this case, we also have to complete the lifting work of the 56-meter, 102-ton ultra-long and overweight ground wall. ”

"There were deformation of the reinforcement cage and a series of safety problems during the hoisting process, but the project team made targeted configurations. In order to make the construction more secure, we chose Sany SAC4000T7 to undertake the main crane task.Compared with products of the same level, the body is shorter, and it is more convenient to enter and exit the site, no matter how narrow the construction site, it basically comes and goes freely.”

Wei Weifeng, the operator of the SAC4000T7 of Wenzhou Xiangyun Machinery Equipment Leasing Co., Ltd., said: "This equipment is very stable to operate, the lifting torque is large, the performance is much better than other equipment, the counterweight can be moved back, and it can always be solved in the face of more difficult working conditions。 ”

"It not only overcame the changeable geological conditions, but also solved the problem of spatial scheduling, and helped build the first deep foundation pit in Zhejiang Province - the 52-meter-deep Jiangbei shield receiving shaft, which enabled it to overcome extreme challenges such as ultra-soft formations and pile group obstacle advancement, and successfully crossed National Highway 330 and flood control embankments."

The Jiangbei shield receiving shaft of the Oujiang Beikou Tunnel is 40 meters long and 18.9 meters wide (small well) / 24.6 meters (large well),It is the first super-large diameter composite lining shield tunnel in the country, and also the first tunnel constructed by shield method in Wenzhou City, and the Jiangbei shield receiving shaft is the deepest rectangular foundation pit in Zhejiang ProvinceIt fills the gap in the construction of shield tunnels in Wenzhou rail transit. And SAC4000T7 has left his own footprints here.