piles driven into the ground by hydraulic hammer. working at construction of a new metro line

activity backhoe boor bucket build bulldozer casing concrete construction contractor crawler deep development dig digding digger dirt drilling driven engineer engineering equipment excavate excavating excavation excavator ground groundwork hammer heavy hydraulic industry job line machine machinery machines metro new pile piles piling platform project rail railway reinforced reinforcement site station subway support technology tubular tunnel underground vibrating vibratory working workplace