Drilled shafts, also known as bored piles, are deep foundation elements used to support structures like bridges and buildings. They are created by drilling a hole into the ground and then filling it with concrete. This method allows for strong support in various soil conditions, making it suitable for heavy loads. The construction of drilled shafts involves specialized equipment, such as drilling rigs, to ensure precision and stability. Once the hole is drilled, reinforcing steel bars, or rebar, may be added before pouring concrete. This process helps to create a solid foundation that can withstand environmental forces and heavy structural loads.