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Concrete Mix Design Calculation for M20, M25, M30 Concrete with Procedure & Example Concrete mix design is the process of finding right proportions of cement, sand and aggregates for concrete to achieve target strength in structures. So, concrete mix design can be stated as Concrete Mix = Cement:Sand:Aggregates. The concrete mix design involves various steps, calculations and laboratory testing to find right mix proportions. This process is usually adopted for structures which requires higher grades of concrete such as M25 and above and large construction projects where quantity of concrete consumption is huge.. Benefits of concrete mix design is that it provides the right proportions of materials, thus making the concrete construction economical in achieving required strength of structural members. As, the quantity of concrete required for large constructions are huge, economy in quantity of materials such as cement makes the project construction economical. Concrete Mix de...

The slump test measures the consistency of fresh concrete before it sets. It is performed to check the workability of freshly made concrete, and therefore the ease with which concrete flows How is slump measured? Simply defined,  slump  is a  measure  of the consistency of fresh concrete. The  slump  test is a very simple test. The  slump  cone is a right circular cone that is 12 inches high. The base of the cone is 8 inches in diameter and the top of the cone is 4 inches in diameter. Concrete Slump Test Procedure Firstly, the internal surface of the mould is cleaned carefully. Oil can be applied on the surface. The mould is then placed on a base plate. The base plate should be clean, smooth, horizontal and non-porous. The mould is filled with fresh concrete in three layers. Each layer is tamped 25 times with a steel rod. The diameter of this steel rod is  5 ⁄ 8 inch. The rod is rounded at the ends. The tamping should be done u...

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HOW TO MINIMISE THE DEFECTS IN PLASTERING WORK? HOW TO MINIMISE THE DEFECTS IN PLASTERING WORK? MINIMISING DEFECTS IN PLASTERING WORK Defects in plastering work can be minimised by following the below mentioned techniques. The brick and plastering work should be carried out by skilled masons in the best workmanship manner. Bond of brick work should be properly maintained. Efflorescence is removed by rubbing brushes on the damaged surface. A solution of one part of hydrochloric acid or sulphuric acid and five parts of clean water is prepared and it is applied with the help of brushes on the affected area. The surface is then washed with clean water. It should, however be remembered that it is desirable to prevent efflorescence than to cure it. Building material should be selected of superior quality and suitable methods of construction should be employed. Water should not be used to wash the surface so as to remove efflorescence. In that case, soluble salts will be partl...

4 PRIMARY CEMENT COMPOUNDS & THEIR ROLES COMPOUNDS OF CEMENT   cement compounds About 90-95% of a Portland cement is comprised of the four main cement minerals, which are  C 3 S ,  C 2 S ,  C 3 A , and  C 4 AF , with the remainder consisting of calcium sulphate, alkali sulphates, unreacted (free) CaO, MgO, and other minor constituents left over from the clinkering and grinding steps. The four cement minerals play very different roles in the hydration process that converts the dry cement into hardened cement paste.  The C 3 S and the C 2 S contribute virtually all of the beneficial properties by generating the main hydration product, C-S-H gel.  However, the  C 3 S hydrates much more quickly than the C 2 S   and thus is responsible for the early strength development .  The C 3 A and C 4 AF minerals also hydrate, but the products that are formed contribute little to the properties of the cement paste.  These minerals a...

Definition of Continuous frame and Truss Continuous frame A continuous frame is a structure which is dependent for its stability and load carrying capacity, upon the ability of one or more of its joints to resist moment. In other words, one or more joints in continuous frame are more or less rigid. Truss or articulated structures A truss or an articulated structure, composed of bars, connected by frictionless pins at joints, and arranged so that the area enclosed within the boundaries of the structure is sub-divided by the bars into geometrical figures usually triangles. Or A truss is an assemblage of members or bars forming a framework of different geomteric figures usually triangles

✡  PRIMAR REQUIREMENTS OF FORMWORK REQUIREMENTS OF FORMWORK REQUIREMENTS OF FORMWORK – QUALITY, SAFETY & ECONOMY In the selection of materials for formwork, the three general principles  of quality ,  safety  and  economy must be paramount. Material quality can ensure safety, and significantly contributes to the achievement of economy. Formwork failure can result in loss of life and always causes catastrophic financial loss. Some general guidelines can be given for form face and framing materials, and for the associated components. These can be covered under the headings of Strength Stiffness Impact Resistance Durability Weight Accuracy Compatibility Insulation 1.   STRENGTH The material strength must be adequate to resist the forces anticipated. This is not only a structural design requirement, but also an essential safety aspect. 2.   STIFFNESS The structural movement under load must be small and predictable....

Civil Engineering Classes HOW TO DETERMINE WEIGHT VOLUME RELATIONSHIP OF SOIL? [STEP BY STEP] WEIGHT VOLUME RELATIONSHIP OF SOIL The physical properties of a soil give insight as to the identification of the soil and the determination of its characteristics and load response. These properties can be determined by performing a laboratory analysis on undisturbed soil samples obtained during the test boring process. The laboratory analysis should be performed in accordance with the following ASTM Standard: D-854: Test Method for Specific Gravity of Soils It should be noted that laboratory analyses are performed under controlled conditions with exacting materials and equipment. The results of such analyses may be considered to be accurate. A field sample of undisturbed soil will contain three separate and distinct constituents – solids, water, and air. One of the important properties that must be determined in the laboratory analysis is tha...

DIFFERENCE BETWEEN PLASTERING & POINTING PLASTERING Applying mortar coats on the surfaces of walls, columns, ceiling etc. to get smooth finish is termed as plastering. Mortar used for plastering may be lime mortar, cement mortar or lime-cement mortar. Lime mortar used shall have fat lime to sand ratio of 1 : 3 or 1 : 4. If hydraulic lime is used mix proportion (lime: sand) is 1 : 2. Cement mortar of 1 : 4 or 1 : 6 mix is very commonly used for plastering, richer mix being used for outer walls. To combine the cost effectiveness of lime mortar and good quality of cement mortar many use lime-cement mortar of proportion (cement : lime : sand) of 1 : 1 : 6 or 1 : 1 : 8 or 1 : 2 : 8. The objective of plastering are: To conceal defective workmanship To give smooth surface to avoid catching of dust. To give good look. To protect the wall from rain water and other atmospheric agencies. To protect surfaces against vermit.   Requirement of good plaster are: It sh...