1 Next finish the edges. I used a rolled edge on my serger but you could use any overcast stitch on your sewing machine or even a zig zag. you just want something that will prevent the edges from unraveling.  Finally fray check the corners so that they stay in tact.
To assess the performance of nickel-titanium reinforced concrete bridges, the researchers analyzed three types of bridge columns: traditional steel and concrete, nickel titanium and concrete, and nickel titanium and engineered cementitious composites, which include cement, sand, water, fiber and chemicals.
Today, many people call Rockville Bridge the longest stone-arch bridge in the world, but that's only partly trueâonly the visible outer layer of its form is stone. The piers and spandrels (the area between the arches) are filled with concrete, making it technically a composite structure. In all, the bridge required not only 220,000 tons of stone but an estimated 600,000 barrels of cement. Measuring 3,820 feet long, it carries four tracks at an elevation fifty-two feet above the river's low-water mark. The price tag was $975,150. The bridge opened on March 30, 1902.