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#Plastering,#Requirements of good plastering

  Plastering is coating which may apply by thin successive layers on a vertical supports of masonry or concrete with a decorative and/or protection aim or to standardize a surface need to support another coating (paint for example).  And plastering worker is a worker who works the mortar covering on walls and usually builds work where the cement or the lime is one of the main constituent. Before starting plastering the structure which is required for plastering should chiseled used for surface to holding the mortar but in the case of ribbed slab no need of chiseling because HCB can trap the mortar easily. Plastering work has three coats (layers):- 1,First coat “berarigirf” 🔸Mix proportion, 1:4 (cement sand by volume with sufficient water) of mortar 🔸Spread by trowel & allowed to cure for 24 hrs before applying second coat.  🔸Has thickness of 0.5 – 1 cm , which is plastered by mortar 2,Second coat “mulet” This layer is about 1.5cm-2.5cm which is done by mortar...

What is SEGREGATION and its cause?

What Is   Segregation ?   Segregation of concrete means  separation of ingredients from design fresh concrete  resulting in the non-uniform mix . More specifically this implies the separation of coarse  aggregates from the mortar because of differences in size, density, shape and other  properties of ingredients in which they are composed. SEGREGATION Segregation is a separation of cement from aggregate This is caused due to improper water cement ratio  This is also caused when concrete is poured about more then 1.5m height

What is reinforcement cover?

COVER TO REINFORCEMENT ✔️ COVER TO REINFORCEMENT   ES EN 1992-1-1:2014 Definition of cover according to this code is " the concrete cover is the distance between the surface of the reinforcment  closest to the nearest concrete surface". ( ES EN 1992-1-1:2015 Article 4.4.1.1 )  "The nominal cover shall be specified on drawings." ( ES EN 1992-1-1:2015 Article 4.4.1.1[2]) Cₙₒₘ=Cₘᵢₙ+ΔCdâ‚‘áµ¥  (ES EN 1992-1-1:2015, equation 4.1) Where :- Cₙₒₘ is the nominal cover Cₘᵢₙ is the minimum cover ΔCdâ‚‘áµ¥ is allowance in design deviation. I. Minimum cover( Cₘᵢₙ ) The minimum cover shall be provided in order to ensure( ES EN 1992-1-1:2015 Article 4.4.1.2[2])  the safety transmission of bond forces 1 the protection of the steel against corrosion. 2 an adequate fire resistance 3 the greater of value of Cₘᵢₙ satisfying both bond and environmental conditions shall be used ( ES EN 1992-1-1:2015 ARTICLE 4.4.1.3[2])  Cₘᵢₙ= max {Cₘᵢₙ,b ; Cₘᵢₙ,dᵤᵣ+ΔCdᵤᵣ,γ-ΔCdᵤᵣ,st- ΔCdᵤᵣ,add; 10 mm ...