In the Late Classic Period Yaxchilan was one of the most powerful Maya cities along the course of the Usumacinta, with Piedras Negras as its major rival. Architectural styles in subordinate sites in the Usumacinta region demonstrate clear differences that mark a clear boundary between the two kingdoms.
Answered by The Community. Making the world better, one answer at a time. Steel is not usually considered a composite, as it is macroscopically homogeneous. However, some steel types, including classical iron-carbon steel, can be considered as metal-matrix composites, as they contain a second phase... sometimes.
This has been the case for over twenty years. Its success is due to the strength and stiffness that can be achieved, with minimum use of materials. The reason why composite construction is often so good can be expressed in one simple way - concrete is good in compression and steel is good in tension.