Prestressed concrete beams are structural elements designed to carry heavy loads while minimizing the risk of cracking. They are made by placing high-strength steel tendons under tension before the concrete is poured. This process compresses the concrete, allowing it to better withstand tensile forces when in use. Once the concrete hardens, the tension in the steel is released, creating a compressive force that enhances the beam's strength and durability. Prestressed concrete beams are commonly used in bridges, parking garages, and large buildings, providing a reliable solution for modern construction needs.