6.3-meter Super Large Diameter Drilling Successfully Concludes

On December 9th, good news came from the construction site of the Xibo Gate Public and Railway Dual-use Bridge. XCMG XR1600E rotary drilling rig successfully completed the 6.3-meter ultra-large diameter drilled pile for the main pier of the bridge, significantly ahead of schedule. The Xibo Gate Public and Railway Bridge is a key project of the Yongzhou Railway. The total length of the bridge is 3118 meters, and it is the world's largest public and railway dual-use bridge with a main span of 1488 meters using a cable-stayed suspension cooperative system. Not only is the construction at risk due to the complex marine environment, but the technical challenges faced by the project far exceed those of other bridges currently built or under construction in China.

The foundation of the main pier of the bridge adopts a total of 18 ultra-large diameter drilled piles with a diameter of 6.3 meters, which are currently the largest diameter drilled piles in China. The depth of the piles is 106 meters, with a water depth of 66 meters and a rock depth of 40 meters. Some of the piles reach a depth of 116 meters. The XCMG XR1600E rotary drilling rig needs to penetrate through layers of highly weathered granite, weakly weathered broken granite, fractured rock, and slightly weathered broken gneiss, among other complex formations, to lay the foundation for the bridge at the deep sea.

The construction platform where the XCMG XR1600E rotary drilling rig is located has relatively hard layers, and the seabed formation is inclined rock. The project team used roller cutter drill bits in four stages to ensure the verticality of the pile foundation. They also broke the conventional staged drilling process, reducing the number of stages and adopting a four-stage drilling process with diameters of 2 meters, 3 meters, 4.5 meters, and 6.3 meters, breaking through the 1.8-meter difference in staged drilling.

The XCMG XR1600E rotary drilling rig is currently the world's largest-tonnage rotary drilling rig, with a maximum drilling diameter of 7.5 meters and a maximum drilling depth of 190 meters. The equipment is designed in a modular manner, making assembly quick and transportation convenient, and it has stable performance.

The impressive performance of the XCMG XR1600E rotary drilling rig marks a new milestone in global foundation construction equipment, providing technical support for more super projects to transition from blueprints to reality.