If strand is tensioned during a hot afternoon and lower temperature concrete is poured on it, what is the expected effect?

When a strand is tensioned and lower temperature concrete is poured on it during a hot afternoon, the expected effect is that it will gain strength. This process relates to the behavior of concrete under temperature conditions and its curing process.

When the concrete is poured at a lower temperature, it undergoes hydration, which is a chemical reaction between the cement and water that leads to hardening. The tensioned strand is designed to work in a specific manner; as the concrete cures and hardens, it begins to bond with the strand, effectively transferring the load between the two materials.

The fact that the strand is tensioned means that it is placed under greater stress, and as the concrete gains strength during curing, this effectively increases the overall tensile strength of the composite system (concrete plus tensioned strand). If everything is functioning correctly, the tension applied to the strand will help the concrete resist future loads, thereby contributing to its structural integrity.

In summary, the interaction between the tensioned strand and the curing concrete typically leads to an increase in strength as the bond between them forms properly, effectively enhancing the structural performance of the system.