Particularly in Zone A or the front area, they focused on drilling through the overlapping concrete slabs, breaking them into small rocks before pulling out the steel bars and gradually drilling as deep as possible, alternating with spraying water to reduce dust that spreads throughout the area. Similarly, in Zone D, they used drilling equipment to inspect for cavities and elevator shafts and fire escapes at both points, which engineers assessed as potentially strong structural points and where people might be trapped.
credit : สล็อต