Near what materials is welding not permitted in concrete construction?

Welding is not permitted near strands, whether prestressed or not, during concrete construction due to the potential for damaging the steel reinforcement. The high temperatures involved in the welding process can adversely affect the structural integrity and performance of prestressed strands. These strands are designed to carry significant loads, and any changes to their properties—such as heat-induced weakening or changes in their bond characteristics—can lead to catastrophic failures in the concrete structure.

While there may be concerns about other materials, such as the potential for igniting wood fibers or the impact of heat on concrete mixtures, the critical aspect with prestressed strands is that they are integral to the structure's load-bearing capacity. Thus, maintaining their strength and performance is paramount, making it essential to avoid welding near these components. This guideline helps ensure the safety and durability of concrete constructions, highlighting the importance of proper materials handling and the specific hazards associated with welding practices.