Magnel
Magnel refers to a type of prefabricated concrete beam developed in France during the mid-20th century. These beams were designed by engineer André Magnel and became widely used in bridge construction. The key innovation of Magnel beams was their use of prestressed concrete, a technique where internal stresses are induced in the concrete before it is subjected to external loads. This prestressing significantly increases the concrete's tensile strength and load-bearing capacity, allowing for longer spans and more slender structures compared to conventional reinforced concrete.
The design of Magnel beams typically involved channels cast into the concrete through which steel tendons