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METHOD OF MEASUREMENT- REINFORCED/PLAIN CEMENT CONCRETE (CAST IN SITU)- AS PER IS 1200-PART-II

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DIMENSIONS - Dimensions shall be measured to nearest 0·01 m except for the thickness of slab which shall be measured to nearest 0·005 m. Areas shall be worked out to nearest 0·01 square metre.   Cubic contents shall be worked out to nearest 0·01 cubic metre. STAGE OF MEASUREMENT- Work shall be measured under the following categories in convenient stages stating the height or depth:  Below ground/datum level.  Aboveground/datum level.  NOTE- The ground/datum level shall be dcfined in each case. CEMENT CONCRETE WORKS Concrete works shall be measured under the following categories.  Works in plain/reinforced/prestressed concrete shall each be measured  separately.  Works in precast and cast in situ concrete shall be kept separate. Unit of Measurement-Unless otherwise stated all concrete work shall be measured in cubic metres. DEDUCTION- No deduction shall be made for the following- Ends of dissimilar materials for example, beams, posts, girders...
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UNDERGROUND CONCRETE SURFACE PROTECTION- COAL TAR EPOXY COATING

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COAL TAR EPOXY COATING- Coal tar epoxy coating is a heavy-duty protective polymer that blends epoxy resins with coal tar pitch to form a tough, black, high-solids coating for steel and concrete surfaces. It is prized for its exceptional resistance to corrosion, chemicals, abrasion, and water, making it ideal for use in extremely corrosive and submerged environments like underground pipelines, sewage treatment plants, and marine infrastructure COMPOSITION OF COAL TAR EPOXY Field of Application - Corrosion resistant coating for concrete and metal structures such as:  • Crude oil storage tanks / underground structures  • Dams, Barrage gates, Penstocks.  • Foundation walls and sumps.  • sewage treatment plant, underground pipelines  • Splash zones in docks & harbors Application Methodology  -  Surface Preparation   • Steel: blast cleaned to ISO-Sa21/2 and remove dust, flakes, oil, grease or other loose foreign particles. • In case of new concrete,...
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TYPES OF GROUT

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   ðŸ‘‰ GROUTS SPECIFIED ARE OF THREE TYPES : ➤ TYPE G1:  A PROPRIETARY NON-SHRINK CEMENTITIOUS, NON-METALLIC, NON CORROSIVE GROUT WITH MINIMUM CUBE CRUSHING STRENGTH OF 40 N/mm2 AT 28 DAYS, WHICH SHALL BE INSTALLED IN ACCORDANCE WITH THE MANUFACTURER'S WRITTEN INSTRUCTIONS. THIS TYPE OF GROUT SHALL BE USED FOR MAJOR STEEL STRUCTURES AND  STATIONARY EQUIPMENT. ➤ TYPE G2: A PROPRIETARY EPOXY GROUT WHICH SHALL BE MIXED AND INSTALLED IN ACCORDANCE WITH THE MANUFACTURER'S WRITTEN INSTRUCTIONS.  THIS TYPE OF GROUT SHALL BE USED FOR ALL MACHINERY,PUMPS AND RECIPROCATING MACHINES.  IT SHOULD HAVE MINIMUM COMPRESSIVE STRENGTH OF 85N/mm² AT 7 DAYS. ➤ TYPE G3: SAND-CEMENT GROUT. CEMENT SHALL BE ORDINARY PORTLAND CEMENT IN ACCORDANCE WITH IS 8112 / IS 12269 AS APPLICABLE. SAND SHALL MEET THE REQUIREMENTS FOR FINE AGGREGATE AS SPECIFIED IN IS 383.  THE SAND-CEMENT MIX SHALL BE SUCH THAT THE COMPRESSIVE STRENGTH OF THE GROUT SHALL NOT BE LESS THAN 14N/...
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Sampling of Concrete Cubes for Test -As per IS 516-1959

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 Blog By Er. Navneet Kumar Sampling of Concrete Cubes for Test -As per IS 516-1959 Size of Test Specimens -  Test specimen cubical in shape shall be 15 X 15 X 15 Cm. If the largest nominal size of the aggregate does not exceed 2 cm.  10 cm cubes may be used as an alternative.  Cylindrical test specimens shall have a length equal to twice the diameter. They shall be 15 Cm in diameter and 30 cm long. Cube Moulds- The cube mould shall be of  metal, preferably steel or cast iron, and stout enough to prevent distortion.  The height of the mould and the distance between opposite faces shall be the specified  size + 0·2 mm.  The angle between adjacent internal face and between internal faces and top and bottom planes of the mould shall be 90° + 0.5°. The interior faces of the mould shall be plane surfaces with a permissible variation of 0·03 mm.  The base plate shall be of such dimensions as to support the mould during the filling without le...
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What is characteristic strength of concrete in flexure ?

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Blog By Er. Navneet Kumar What is characteristic strength of concrete in flexure ?  ðŸ‘‰Characteristic strength of concrete is the value of strength of concrete below which not more than  5 % of test results are expected to fail.               It is denoted by fck.                                                           fck = fm- 1.65σ        Where fm= Target mean strength & σ = standard deviation. Note- 👉Concrete is designated by characteristic cube strength of concrete at 28 days. 👉No material is truly homogeneous , so strength of similar concrete varies in different testing. 👉For most of the engineering materials ,probability is symmetrical about mean and such a curve is called Normal Probability distribution curve.               ...
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What is Engineering Mechanics & Strength of Materials ?

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ENGINEERING MECHANICS STRENGTH OF MATERIALS Ø   In this we assume that the body is perfectly rigid (the type of material which doesn’t undergo any change in geometry of the body when load is applied). Ø   In this we assume that the body is perfectly elastic (the type of material which undergoes change in geometry of the body when load is applied) Ø   It deals with the study of external force & their effect on rigid body. Ø   It deals with the effect of external force & their effect as internal resting force in bodies. Ø   In rigid body, stress will develop but no strain. Ø   In deformable bodies both stress and strain will develop. Note- Concept of Ideal body or rigid body is hypothetical and it doesn’t exist.    
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English Bond in Brick Masonry Wall

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 * English Bond in Brick Masonry Wall This is most commonly used wall, for all thickness and considered to be strongest . This bond consist of alternate courses of headers and stretchers .  In this bond joints of header course come over each other, similarly joints of stretcher course come over each other. A queen closer is used after first header (qunion header) in each header course to break vertical joints in successive courses.
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