Arch+OP

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 * Arch **: A curved structural member spanning an opening or recess. The wedge shaped elements that make up an arch keep one another in palce and transform the vertical pressure of the structure above into lateral pressure.

**Parts of an arch **: keystone, soffit, spring line, springer, voussoir

A masonry arch 1. Keystone 2. Voussoir 3. Extrados 4. Impost 5. Intrados 6. Rise 7. Clear span 8. Abutment

There are basic arch styles that frame and support doors, windows, porches, and other wall openings in homes.

2.Tudor arches are often described as "flattened" Gothic arches. They feature a point at the crown, but the span is much wider than the Gothic style.  3. A Flat arch, also known as jack or straight arch, extends straight across an opening with no curvature, creating a horizontal emphasis. 4.A narrow, pointed opening is the hallmark of a Gothic arch. The Gothic arch developed as a more sinuous and elegant successor to the Roman arch and was widely used in cathedrals of the Middle Ages such as Notre Dame in Paris. 5. A Moorish, or horseshoe arch, extends beyond a semi-circle. The top of the arch is rounded and then curves in slightly before descending.
 * 1) A Roman arch is a strong, rounded arch that forms a semi-circle. Often made of masonry, Roman arches still stand in the Coliseum.