Recently, during the construction of the Zijing Tunnel of the Yuchixu Expressway Section 4 project undertaken by Chongqing Zhonghuan Construction Co., Ltd.,CRCHIDGZ15The 0G multifunctional drilling rig successfully completed the advanced probing holes required by the project, completing a total of 6 advanced probing holes with a cumulative advanced drilling depth of 228 m and a maximum single-hole drilling depth of 90 m, providing safety assurance for subsequent tunnel construction.

CRCHI DGZ150G multifunctional drilling rig

The geology in Southwest China is complex and variable, with adverse geological conditions such as fault fracture zones, water-rich strata, large deformation of soft rock, and karst caves being particularly prominent, constituting major unfavorable factors affecting safe tunnel construction.

As a key control project of the Yuchixu Expressway Section 4 project in Chongqing, the Zijing Tunnel runs through Zijing Mountain, where the mountain is steep, the rock is hard, the terrain is complex, and construction is difficult. Facing complex geological conditions, the CRCHI DGZ150G multifunctional drilling rig demonstrated stable and efficient operating performance, completing multiple advanced probing holes including 90 mm diameter at 90 m depth and 102 mm diameter at 60 m depth, with a comprehensive construction speed of over 25 m/h and an effective drilling time for a single 3 m drill rod as fast as 2 min. During construction, switching the power head impact frequency and rotary gear according to different rock strata became the key to efficient drilling with the multifunctional drilling rig. On-site personnel affirmed the rig's safety, convenience, efficiency, and environmental performance.

CRCHI's advanced forecasting construction tool, combined with the rich construction experience of Zhonghuan Construction Co., Ltd., will continue to support the safe and efficient construction of the Yuchixu Expressway project.