Which block is utilized instead of a traditional CMU in certain applications?

The still block is specifically designed for use in certain applications where a traditional concrete masonry unit (CMU) would not be suitable. This type of block often features a hollow cavity that can help to accommodate various requirements, such as the inclusion of reinforcing bars or for applications that demand a specific structural capacity. For instance, still blocks can be utilized in situations where lateral loads are significant, making them ideal in areas subjected to seismic activity or heavy wind loads.

The unique design and properties of still blocks differentiate them from standard CMUs, offering customized solutions tailored to specific engineering needs. This flexibility allows for more efficient construction and enhanced structural performance. In contrast, other blocks mentioned—like U-shaped, lintel, or half blocks—serve distinct functions but do not typically replace traditional CMUs in the broader context of masonry applications.