Concrete outperforms wood as a construction material, and won't burden building owners with constant repair and maintenance costs. Versatile, long-lasting and durable, concrete is a cost-effective, sustainable choice for both residential and commercial buildings. When it's built with concrete, it's built to last. Concrete is a building material that gains strength over time. Concrete's 100-year service life conserves resources by reducing the need for reconstruction. Concrete is durable - it resists weathering, erosion and natural disasters, needs few repairs and little maintenance, adding up to a solid investment.
Frontier refers to a contrasting region at the edge of a European-American line of settlement. American historians cover multiple frontiers but the folklore is focused primarily on the 19th century west of the Mississippi River.
frontier c.1400, from O.Fr. fronter, from front brow (see front). Originally the front line of an army, sense of borderland is first attested 1413. In reference to N.Amer., from 1676; later with a specific sense:What is the frontier? ... In the census reports it is treated as the margin of that settlement which has a density of two or more to the square mile. [F.J. Turner, The Frontier in American History]Frontiersman is from 1782.