Some facts about the arch bridge include its architect and the age of the oldest arch bridges. In architecture, the arch bridge design has been used for over 2,000 years and can be found in Roman, Baroque and Renaissance structures.Know More
The oldest stone segmental arch bridge is the Anji Bridge, commonly known as the Zhaozhou Bridge, which is found in China. The bridge was initially constructed in 605 AD and, as of 2015, has survived over 1400 years.
The arch bridge design was also commonly used for bridges and in aqueducts during the Roman era.
An arch bridge that is constructed from stone does not require mortar in its construction. However, this means that additional support systems or scaffoldings are necessary during the construction process. Two separate segments of an arch structure do not have structural integrity on their own. The structural strength of the arch design is generated when both sections meet in the middle, allowing force to dissipate outwards.
Materials used in modern arch bridges include pre-stressed concrete and steel. The strength of modern materials allows for larger arches when compared to Roman stone arch bridges. Arches found in modern bridges can span from 200 to 800 feet.Learn more about Landforms
Interesting facts about the Grand Canyon are that its oldest rocks date back two billion years, it represents one-third of Earth's history and it's not the biggest canyon in the world. The Grand Canyon ranges in age from 250 million years old at the highest rocks to two billion years old at the lowest rocks.Full Answer >
One fun fact about sand dollars is that these animals are closely related to sea urchins. In addition, the white or off-white sand dollar skeletons found on beaches are called "tests," and their five-jawed mouths are at the center of the star-shaped markings on the tests.Full Answer >
The Canadian Shield is a plateau that covers approximately half of Canada, as well as most of Greenland and a portion of the northern United States. It is the oldest part of the North American plate and the largest formation of exposed Precambrian rock in the world.Full Answer >
Most existing valleys have been formed by geological conditions that happened thousands of years ago. Rivers and streams are responsible for forming most of the modern valleys. The flowing waters cut valleys in "V" or "U" shapes, carving steep-walled sides and narrow floors. Other valleys have been made from large glaciers. The massive blocks of snow and ice slowly move downhill, leaving in their wake a hollowed-out valley.Full Answer >