Why construction is different

K Ringen1, A Englund, L Welch

  • 1Center to Protect Workers' Rights, Washington, DC 20001, USA.

Occupational Medicine (Philadelphia, Pa.)
|April 1, 1995
PubMed

Related Concept Videos

Masonry01:28

Masonry

Masonry, known for its strength, durability, and aesthetic versatility, encompasses construction with solid stone or man-made units like bricks, clay tiles, terra cotta, and concrete blocks, combined to form structures like walls, floors, and arches. These units are placed in a systematic fashion, known as coursing, and are bound together using mortar—a mixture typically made of water, cement, and sand.
The process of building with masonry is hands-on and can be executed with basic tools. A...
Stone Masonry01:29

Stone Masonry

Stone masonry is a construction technique that uses individual stones to build structures and can be categorized into two main types: rubble and ashlar. Rubble masonry uses uneven, naturally shaped stones such as river rocks or fragments from quarries. This method often requires the mason to select and possibly shape each stone to fit the designated space, ensuring a proper build, even with irregular stone sizes and shapes. Ashlar masonry, on the other hand, employs uniformly cut stones that...
Laying Concrete Masonry01:16

Laying Concrete Masonry

Constructing a concrete masonry wall involves a series of steps designed to ensure durability, stability, and alignment. The construction starts with preparing the base, which includes cleaning the area where the wall will be erected. The next step involves spreading mortar where the first row of concrete blocks will be laid, typically starting at a corner section to help define the wall's boundaries.
Mortar application focuses on the face shells of the blocks, the sides that face outward, and...
Concrete01:20

Concrete

Concrete is a vital construction material extensively used worldwide, primarily valued for its strength, durability, and versatility, which it provides for various structural designs. Concrete generally comprises ingredients like Portland cement, coarse gravel, fine sand, and water. Concrete can be mixed by simple hand methods or industrially at computer-controlled plants. The mixture consists of aggregates and a paste made from water and Portland cement. This paste coats the aggregates and,...
Prestressed Concrete01:20

Prestressed Concrete

Prestressed concrete is a construction technique designed to enhance the strength and durability of concrete structures. This method involves the application of a pre-set tension to high-strength steel strands used as reinforcement before the concrete is subjected to its working loads. The primary aim of prestressing is to place the concrete in a state of compression, in order to counteract the tensile forces it will experience in service. This pre-compression helps prevent crack formation in...
Mass Concreting01:22

Mass Concreting

Mass concreting refers to the process of placing large volumes of concrete, such as in gravity dams. The heat generated during the cement hydration process and differential cooling rates within the concrete mass can lead to a temperature gradient, which can result in thermal cracks in the concrete mass.
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...