Mud

In the construction industry, mud is a semi-fluid material that can be used to coat, seal, or adhere materials.[1] The term "mud" can be used for various semi-fluid materials used in construction including slurry, mortar, plaster, stucco, and concrete.[1]

Mud, cob, adobe, clay, and many other names are historically used synonymously to mean a mixture of subsoil and water possibly with the addition of stones, gravel, straw, lime, and/or bitumen. This material was used a variety of ways to build walls, floors and even roofs. For thousands of years it was common in most parts of the world to build walls using mudbricks or the wattle and daub, rammed earth or cob techniques and cover the surfaces with earthen plaster.

Mud house in 'Amran, Yemen

Mud can be made into mud bricks, also called adobe, by mixing mud with water, placing the mixture into moulds and then allowing it to dry in open air.[2] Straw is sometimes used as a binder within the bricks, as it makes them a composite. When the brick would otherwise break, the straw will redistribute the force throughout the brick, decreasing the chance of breakage.[3] Such buildings must be protected from groundwater, usually by building upon a masonry, fired brick, rock or rubble foundation, and also from wind-driven rain in damp climates, usually by deep roof overhangs. In extremely dry climates a well-drained flat roof may be protected with a well-prepared (puddled) and properly maintained dried mud coating, viable as the mud will expand when moistened and so become more water resistant.[4] Adobe mudbricks were commonly used by the Pueblo Indians to build their homes and other necessary structures. In some countries there are entire cities made of mud brick houses. Cow dung and biomass are added to regulate indoor climate.[5]

Mud that is mostly clay, or a mixture of clay and sand may be used for ceramics, of which one form is the common fired brick. Fired brick are more durable but consume much more energy to produce.

Stabilized mud (earth, soil) is mud which has had a binder such as cement or bitumen added. Examples are mudcrete, landcrete, and soil cement.

Mud can provide a home for numerous types of animals, including varieties of worms, frogs, snails, clams, and crayfish. Other animals, such as hippopotamuses, pigs, rhinoceroses, water buffalo and elephants, bathe in mud in order to cool off and protect themselves from the sun. Submerged mud can be home to larvae of various insects.

Mud plays an important role in the marine ecosystem. The activities of burrowing animals and fish have a dramatic churning effect on muddy seabeds. This allows the exchange and cycling of oxygen, nutrients, and minerals between water and sediment.[6]

Below the surface, the burrows of some species form intricate lattice-like networks and may penetrate a meter or more downwards. This means that the burrowed mud is a productive habitat, providing food and shelter for a wide range of mud-dwellers and other animals that forage in and over the mud.[6]

Mississippi mud pie is a chocolate based dessert pie.[10] Children's recipes for "mud" also exist, which is generally a chocolate or cornstarch-based sludge used more for visual appeal than actual taste. However, it does not contain real mud.[11]

A mud bath is a bath of mud, commonly from areas where hot spring water can combine with volcanic ash. Mud baths have existed for thousands of years, and can be found now in high-end spas.

Mud wallows are a common source of entertainment for children. Mud wallows can be any shape, size, depth and some can have water as well as mud. Usually wallows are shallow dips in the ground that have been flooded and were full of dirt and those two have mixed to make a squishy mud wallow.

Mud bogging is a form of off-road motorsport popular in Canada and the United States in which the goal is to drive a vehicle through a pit of mud or a track of a set length. Winners are determined by the distance traveled through the pit. However, if several vehicles are able to travel the entire length, the time taken to traverse the pit will determine the winner.

Mud runs are a popular activity involving mud. Participants run a distance of 5 kilometres (3 mi) to as long as 20 kilometres (10 mi), while crawling through mud bogs, and battling other obstacles.[12][13][14]

A buffalo wallowing

• Mud is used in mud wrestling as a form of entertainment.
• Mud can be used in a dunk tank.
• Dirt biking involves biking through muddy tracks and courses.

A rhinoceros wallowing

• Baseball rubbing mud is used to remove the sheen from new baseballs.
• Children often like to make mud pies, throw mud at each other and play barefoot and cover their bare feet in mud and squish it between their toes.
• Albuquerque and other towns across the United States such as Gillette, Wyoming, hold a yearly event in which participants play volleyball in a giant mud pit.
• Mud can be smeared across the skin as a repellent from mosquitoes.
• Many animals cover themselves in mud (wallowing) to cool off.