Civil engineering. Cellular Lightweight Concrete $($CLC$)$ is a type of concrete that is known for its low density and high thermal insulation properties. It is produced by mixing a combination of lightweight aggregates, foam, and cementitious materials. The foam is generated by adding a foaming agent to the mixture, which creates air bubbles and reduces the overall density of the concrete.

Here are some key features and advantages of Cellular Lightweight Concrete:

$1.$ Low Density: CLC has a significantly lower density compared to traditional concrete. The density can be adjusted based on the desired application, ranging from $400$ kg$/$m$^3$ to $1,800$ kg$/$m$^3.$ The lower density results in reduced dead load on structures, making it suitable for applications where weight reduction is important.

$2.$ Thermal Insulation: CLC has excellent thermal insulation properties due to the presence of air voids within the concrete. These air voids act as insulating pockets, reducing heat transfer and improving energy efficiency in buildings.

$3.$ Fire Resistance: Cellular Lightweight Concrete exhibits good fire resistance due to its low thermal conductivity and ability to retain water. It can withstand high temperatures for a longer duration compared to conventional concrete.

$4.$ Acoustic Insulation: CLC provides effective sound insulation due to its porous structure. It can reduce noise transmission, making it suitable for applications where soundproofing is required.

$5.$ Workability: CLC offers good workability, allowing for easy casting and molding into various shapes and sizes. It can be easily cut, drilled, and shaped using standard tools.

Applications of Cellular Lightweight Concrete in Civil Engineering:

$-$ Building Construction: CLC is used in the construction of walls, partitions, and roofs for residential, commercial, and industrial buildings. It provides thermal comfort, reduces energy consumption, and improves indoor air quality.

$-$ Insulation and Fillings: CLC is utilized as insulation material in cavity walls, underfloor insulation, and roof insulation. It can also be used as lightweight fillings in voids, trenches, and backfilling applications.

$-$ Precast Elements: CLC is suitable for manufacturing precast elements such as blocks, panels, and slabs. These elements are lightweight, easy to handle, and offer excellent thermal insulation.

$-$ Road Construction: CLC can be used in road embankments, lightweight backfill, and slope stabilization. Its low density reduces the load on the subgrade and improves overall stability.

Question: Cellular Lightweight Concrete is known for its low $----------$ and high thermal insulation properties. A$)$ Strength B$)$ Density C$)$ Durability D$)$ Flexibility