Underpinning is a procedure used to repair, strengthen, or increase the depth of an existing foundation by lowering the footing to permit it to rest on more supportive soil. In this technique, a new foundation is built under the old foundation, or the old foundation is repaired. Methods of Underpinning Pit Method Cantilever needle beam method Pier and beam … Read more
When dry gypsum powder is mixed with water it hardens. This material which can be applied over brick, block, or concrete surface to form a smooth surface is known as gypsum plaster. Gypsum plaster can be applied directly without any surface preparation. It takes 25 to 30 minutes to set and provide a white surface … Read more
The parapet wall is a protective barrier that is provided around the perimeter of the roof and balcony. It is constructed for safety purposes. The height of the wall should not be less than 760 millimeters. Parapet walls can be made utilizing various materials like reinforced cement concrete, steel, aluminum, glass, etc. The parapet wall … Read more
What is Cavity Wall? A cavity wall or hollow wall is constructed with two separate walls called leaves-or skins with a cavity gap or space in between two walls. Both walls are joined together by metal ties. (see figure below) The primary purpose of the cavity wall is to provide better insulation in the building. It … Read more
Workability of concrete is the characteristic of freshly mixed concrete which defines the ease and homogeneity with which it can be mixed, transported, placed, compacted, and finished as described by ACI Standard 116R-90 (ACI 1990b). As per ASTM “that property determining the effort needed to manipulate a freshly mixed quantity of concrete with minimum loss … Read more
Polymer Concrete Polymer Concrete is a special type of Concrete that utilized Polymer instead of Lime-type Cement as a binder. In certain circumstances, Polymer is used in addition to Portland cement to make Polymer Cement Concrete (PCC) or Polymer Modified Concrete (PMC). The traditional concrete is puros due to the presence of air voids, water … Read more
Creep in Concrete Elastic and long-term deformation of Concrete under a continuous load is called Creep. Long-term stress alters the shape of the concrete structure and deformation occurs along the direction of applied stress. After the removal of stress, the strain is reduced immediately. The amount of the reduced strain is equal to the elastic … Read more
Shrinkage is an intrinsic characteristic of concrete. The shrinkage in concrete can be characterized as the volume changes observed in concrete because of loss of moisture at various stages due to different reasons. Concrete Shrinkage The loss of moisture content due to Evaporation in concrete is known as the shrinkage of concrete. In the first … Read more
Shotcrete Shotcrete is also known as sprayed concrete. Shotcrete is pneumatically projected or sprayed with the help of a nozzle at high velocity on the prepared surface. The complete system is also called spraycrete. Shotcrete is poured and consolidated at the same time due to the load ejected from the nozzle. Shotcrete can be placed … Read more
Sunken Slab The sunken slab is provided in the washroom or laundry areas where water pipes are installed below the floor level. The depth of the sunken slab is normally 20 cm to 30 cm below the floor level. Depth depends upon the size of the duct or any other pipes installed below the floor … Read more