Which cement type is unsuitable for a multistory reinforced concrete building needing rapid use?

In the context of a multistory reinforced concrete building that requires rapid use, Type IV cement is considered unsuitable due to its low heat of hydration, which results in a slower strength gain compared to other types. Type IV is specifically designed for massive structures like dams, where the heat generated from hydration needs to be minimized to prevent cracking.

For multistory buildings that need to be put into service quickly, rapid strength development is crucial, especially to support construction schedules and ensure the building can withstand loads early in the process. Type III cement, known for its high early strength, would typically be the preferred choice in such scenarios since it facilitates faster construction timelines. Meanwhile, Type I and Type II cements also offer sufficient strength gains that could be advantageous for a building project, albeit with slower rates than Type III. Therefore, Type IV cement, focusing on slower curing and minimal heat generation, would not meet the demands of rapid construction needed for a multistory building.