Crane accidents can be caused by mechanical failures or human failures in the operations of the cranes. Even the mechanical failures can be a result of improper supervision or maintenance and all point to lack of training and required attention to crane operations by field managers. The Need for Cranes and the Risks Involved Cranes…
Concrete is a basic building block of our everyday world. It’s used in almost every type of structure that we build today. This engineering guide to concrete will give you a variety of information about concrete, including some best practices for various situations. Concrete is one of the most prevalent building materials known to man….
Carbonation is the result of the interaction of carbon dioxide gas in the atmosphere with the alkaline hydroxides in the concrete. Like many other gases carbon dioxide dissolves in water to form an acid. Unlike most other acids the carbonic acid does not attack the cement paste, but just neutralizes the alkalinity in the pore…
In RC buildings, portions of columns that are common to beams at their intersections are called beam-column joints (Figure 1). Since their constituent materials have limited strengths, the joints have limited force carrying capacity. When forces larger than these are applied during earthquakes, joints are severely damaged. Repairing damaged joints is difficult, and so damage…
Liquid water The water molecule is composed of two hydrogen atoms, each linked by a single chemical bond to an oxygen atom. Most hydrogen atoms have a nucleus consisting solely of a proton. Two isotopic forms, deuterium and tritium, in which the atomic nuclei also contain one and two neutrons, respectively, are found to a small degree in water. Deuterium oxide (D2O), called heavy water, is important in chemical research and is also used as…
Dampness prevention methods: The following are the precautions to be taken to prevent dampness in buildings, before applying the various techniques. 1. The site should be located on high ground and well-drained soil to safe guard against foundation dampness 2. All the exposed walls should be of sufficient thickness to safeguard against rain protection (minimum 30 cm)…
The notion that failure of a soil occurs by sliding along a plane on which the shear stress reaches a certain maximum value has lead to the development of shear tests. In such tests a sample is loaded such that it is expected that one part of the asmple slides over another part, along a…
The process of finding a single vector which will have the same effect as a set of vectors acting on a body is known as composition of vectors. The resolution of vectors is exactly the opposite process of composition i.e., it is the process of finding two or more vectors which will have the same…
Irrigation and drainage, artificial application of water to land and artificial removal of excess water from land, respectively. Some land requires irrigation or drainage before it is possible to use it for any agricultural production; other land profits from either practice to increase production. Some land, of course, does not need either. Although either practice may be, and both…
Prestressed concrete pipes have lower construction costs and are more readily repaired in comparison to conventional concrete pipes. Repair of prestressed concrete pipes, in fact, has made things easy for repair and maintenance engineers. Prestressed Concrete – Tension Free Concrete Conventional concrete breaks down when subjected to tensile loads. Concrete is all good for countering compressive loads, but when…