Specification - Reinforcement Bars

Download Specification - Reinforcement Bars

Post on 22-Oct-2014

454 views

Category:

Documents

3 download

Embed Size (px)

TRANSCRIPT

<p>SPECIFICATION OF REINFORCEMENT BARSPROJECT MANAGEMENT-II</p> <p>SUBMITTED BY:</p> <p>SHISHUPAL SINGH</p> <p>SPA/NS/BEM/526 School of Planning &amp; Architecture, New Delhi</p> <p>2</p> <p>SPECIFICATION OF REINFORCEMENT BARS</p> <p>1. O REFERENCES o References to standards i) Is: 432 (Part I) 1982 Indian Standard Specification for Mild Steel and Medium Tensile Steel Bars and Hard-Drawn Steel Wire for Concrete Reinforcement. Part I: Mild Steel and Medium Tensile Steel Bars (Third Revision). ii) Is 8 432 (Part II) 1982 Indian Standard Specification for Mild Steel and Medium Tensile Steel Bars and hard-Drawn Steel Wire for Concrete Reinforcement. Part II Hard-Drawn Steel Wire (Third Revision). iii) IS: 1786-1979: Indian Standard Specification for Cold-Worked Steel High Strength Deformed Bars for Concrete Reinforcement. iv) IS: 1786-1966: Indian Standard Specification for Cold Twisted Steel Bars for Concrete Reinforcement. v) IS: 1566-1982: Indian Standard Specification for Hard Drawn Steel Wire Fabric for Concrete Reinforcement. vi) IS :1786-1985: (Superseding IS : 1139-1966) Indian Standard Specification for High Strength Deformed Steel Bars And Wires for Concrete Reinforcement. vii) IS : 5525 1969: Recommendations for detailing of Reinforcement in Reinforced Concrete works. viii) IS:2502-1999: Code of Practice for Bending and Fixing of Bars for Concrete Reinforcement. ix) IS: 9077-1979: Code of Practice for Corrosion Protection of Steel Reinforcement in Reinforced Brick and Reinforced Cement Concrete Construction x) IS: 10790(Part I):1984: Methods of Sampling of Steel for Pre-stressed and Reinforced Concrete xi) SP: 34 (S&amp;T)-1987; Handbook on Concrete Reinforcement detailing xii) Commentary on CPWD Specifications: Cement Concrete Work</p> <p>SHISHUPASL SINGH</p> <p>M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>3</p> <p>SPECIFICATION OF REINFORCEMENT BARS</p> <p>2.0</p> <p>SCOPE OF WORK</p> <p>The types of reinforcement bars included in the scope of the study are: Mild Steel Medium Tensile Steel Bars High Strength Deformed Steel Thermo-Mechanically Treated Bars Hard Drawn Steel Wires</p> <p>2.1 The scope covers definitions of terms relating to concrete reinforcement. 2.2 The scope covers the requirements of mild steel and medium tensile steel plain bars in round and square sections for use as reinforcement in concrete. 2.3 The scope covers the requirements of hard-drawn steel wire of medium strength for use as reinforcement in concrete. 2.4 The scope covers the requirements for hard-drawn steel wire fabric consisting of harddrawn steel wire with cross wires electrically welded to them for use as concrete reinforcement. 2.5 The scope covers the requirements of deformed steel bars and wires for use as reinforcement in concrete, in the following three strength grades: Fe 415 Fe 500 Fe 550 2.6 The scope covers symbols and approximate dimensions of bends, and bending and fixing procedures for reinforcement. 2.7 The scope covers the general requirements of detailing of reinforcement in reinforced concrete structures. The recommendations may be applied to all reinforced concrete structures with suitable modifications as may be necessary. 2.8 The scope deals with the protection of reinforcement from corrosion in reinforced brick (RB) and reinforced cement concrete (RCC) construction.</p> <p>SHISHUPASL SINGH</p> <p>M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>4</p> <p>SPECIFICATION OF REINFORCEMENT BARS</p> <p>3.0 RELATED WORKS o Formwork</p> <p>oo</p> <p>o</p> <p>o o</p> <p>The formwork shall be designed and constructed so as to remain sufficiently rigid during placing of reinforcement bars and concrete and compaction of concrete. ( IS 6461 : Part 5 : 1972) All rubbish, particularly chippings, shavings and saw dust shall be removed the interior of the forms. The face of the formwork in contact with the concrete shall be cleaned and treated with form release agent.( In the concrete construction industry, form release agents prevent the adhesion of freshly placed concrete to the forming surface, usually plywood, overlaid plywood, steel or aluminum). Form release agent should be applied so as to provide a thin uniform coating to the form without coating the reinforcement.</p> <p>Conduiting o The conduiting of CI pipes for electrical shall be laid as per electrical layout drawings after the placing of reinforcement bars. o Nowhere should it be placed under the reinforcement bars as it may collapse under the load of the reinforcement.</p> <p>Care should be taken not to displace the position of the conduits while working. o Concreting o The concrete shall be deposited as neatly as practicable in its final position to avoid rehandling. o There should not be displacement of any reinforcement or movement of formwork while placing concrete. o 4.0 GENERAL REQUIREMENTS o Submittal of shop drawings: Not relevant o Requirement of qualified staff: The contractor shall appoint well qualified staffs who would execute the work on site. The persons should have special expertise and skills to carry out the required work. o Requirement of tools and equipment: The required tools and equipment for carrying out the works shall be arranged by the contractor. The tools and plant shall be used to satisfy time, cost and quality parameters of work. o General handling, storage and protection requirementso Steel reinforcement stored at the work site shall be placed on platforms, skids, or other supports. This is done so that contact with the ground is avoided and the material is protected from mechanical damage and/or corrosion The space for storage of material shall be provided by the owner.M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>oSHISHUPASL SINGH</p> <p>5</p> <p>SPECIFICATION OF REINFORCEMENT BARSo The steel reinforcement shall be stored by the contractor at site of work in such a way as to prevent distortion and corrosion and nothing extra shall be paid on this account. Bars of different sizes and lengths shall be stored separately to facilitate easy counting and checking. Contractor shall make arrangements for the protection of the materials.</p> <p>o</p> <p>o Environmental requirements:o o Lighting levels shall be maintained at the work place. If natural light is no accessible, then artificial lighting shall be provided at no extra cost by the contractor to ensure quality of work</p> <p>5.0 MATERIALS o Material data: MILD STEEL AND MEDIUM TENSILE STEEL BARS oo o o o o Mild steel bars Medium tensile steel bars 5.1.2 Mild steel bars shall be supplied in the following two grades: Mild steel bars, Grade I designated as Fe 410-S Mild steel bars, Grade II designated as Fe 410-O Medium steel bars, Grade II designated as Fe 540-W-HT Sizes: Mild steel and medium tensile steel bars shall be supplied in the following nominal sizes: Diameter of round bars or side 5, 6, 8, 10, 12, 16, 20, 22, 25, 28, of square bars: 32, 36, 40, 45 and 50 mm Mass the mass of bars shall be in accordance with IS: 1732-1971-f. 5.1.4 Tolerances: The rolling and cutting tolerances shall be in accordance with IS: 1852-1973, IS: 1786 Tolerance on nominal mass Percent Batch Individual Individual sample + sample for coil (-x-) +7 +8 +8 5.1.3 Reinforcement supplied in accordance with this standard shall be classified into the following types:</p> <p>o o</p> <p>Nominal size in mm</p> <p>5.1.5</p> <p>Upto and including 10 Over 10, upto +5 -6 +6 and including 16 Over 16 +3 -4 +4 Physical requirements: The ultimate tensile stress and percentage elongation is determined according to the following table:</p> <p>SHISHUPASL SINGH</p> <p>M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>6</p> <p>SPECIFICATION OF REINFORCEMENT BARS</p> <p>S.No</p> <p>Type and nominal size of bar (min) Mild Steel Grade IFor bars up to and including 20 mm For bars over 20 mm, up to and including 50 mm</p> <p>Ultimate tensile stress (min) 410 410</p> <p>Yield stress (min)</p> <p>Elongation Percentage (min) 23 23</p> <p>1</p> <p>250 240</p> <p>2</p> <p>Mild Steel Grade IIFor bars up to and including 20 m For bars over 20 mm, up to and including 50 mm</p> <p>370 370</p> <p>225 215</p> <p>23 23</p> <p>3</p> <p>Medium Tensile SteelFor bars up to and including 16 mm For bars over 16 mm, up to and including 32 mm For bars over 32 mm, up to and Including 50 mm</p> <p>540 540 510</p> <p>350 340 330</p> <p>20 20 20</p> <p>o</p> <p>Handling, storage and protection5.2.1 Every care should be taken to avoid mixing different types of grades of bars in the same structural members as main reinforcement to satisfy relevant clause of IS: 456. In case of structures, wherever the situation necessitates, the change over shall be made only room any one level onwards. In case of foundations, all foundation elements (footings ring beams, piles and pile caps) shall have the same kind of steel. In the case of columns, all structural elements up to the level of change, where the changeover is taking place should have the same kind of steel as those in columns 5.2.1 The reinforcing steel brought to site of work shall be stored on brick / timber pedestal height, nothing extra shall be paid on this account. 5.2.2 All finished bars shall be well and cleanly rolled to the dimensions and weights specified. They shall be free from cracks, surface flaws, laminations and rough, jagged and imperfect edges and all other harmful defects. 5.2.3 Transporting Reinforcement: Reinforcement shall be transported to the site of work or to the place of storage by such means and in such a manner that the reinforcement is neither damaged nor deformed. The unloading of the reinforcement shall be done at the nearest convenient place where it is to be processed further. Particularly in cases where unloading is required to be done by hand, it is important that the vehicle should be brought as close as possible to the stacking or bending place in order to avoid carrying over long distances. As far as possible, at the time of unloading the bars should be separated by sizes and lengths.</p> <p>SHISHUPASL SINGH</p> <p>M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>7</p> <p>SPECIFICATION OF REINFORCEMENT BARS5.2.4 Storage of Reinforcement: The actual location of the stacking place of reinforcement depends upon the site conditions, but it should be such that the reinforcement could be conveniently received and supplied to the operational centers in the site. On works covering large area;, it might be an advantage to stack the reinforcement at different places close to the areas where they are likely to be used most. In order to ensure that the reinforcement bars are kept in good condition, they should not be left in direct contact with the ground but they should be stacked on top of an arrangement of timber sleepers or the like. Suitable racks may also be used for stacking reinforcement in tiers. Where space is extremely limited, bars may also be stacked vertically but the vertical stacking has the disadvantage that it is more difficult to get the bars in and out and in identifying bars of different sizes and lengths. Whatever method of stacking is adopted, the bars should be stacked in such a way that the various sizes and lengths can be quickly and easily identified. After the reinforcement bars have been bent, they should be placed in the most convenient locations for transport. Flexible bends like stirrups and bends of small 8 diameter bars should be grouped together and bundled for ease of handling. Each bundle of bars or group of bars should have labels affixed to it indicating the bar mark, bending schedule reference number and its position in laying. In storing bars, attention shall be paid to avoiding distortion and to preventing deterioration and corrosion. Whilst a certain amount of hard rust on the reinforcement is considered desirable in reinforced concrete work, care should be taken to ensure that undue rusting or loose scaling do not take place in storage and in such conditions of weather where the reinforcement is likely to get corroded, the stack of reinforcement shall be suitably sheltered.</p> <p>5.2</p> <p>Quality Assurance</p> <p>5.2.1 Submittal of Manufacturers/Suppliers test documents: 5.2.1.1 Unless otherwise specified, general requirements relating to the supply of material, inspection and testing shall conform to IS: 1387-1967. 5.2.1.2 No material shall be dispatched from the manufacturer's or suppliers' premises prior to its being certified by the purchaser or his authorized representative as having fulfilled the tests and requirements laid down in this standard except where the bundle or coil containing the bars is marked with the ISI Certification Mark. 5.2.1.3 The purchaser or his authorized representative shall be at liberty to inspect and verify the steel maker's certificate of cast analysis at the premises of the manufacturer or supplier; when the purchaser requires an actual analysis of finished material, this shall be made at a place agreed to between the purchaser and the manufacturer or supplier. 5.2.1.4 Manufacturer's Certificate: In the case of bars which have not been inspected at the manufacturer's works, the manufacturer or supplier, as the case may be, shall supply the purchaser or his authorized representative with the certificate stating the process of manufacture and also the test sheet signed by the manufacturer giving the result of each mechanical test applicable to the material purchased, and the chemical composition, if required. Each test sheet shall indicate the number or identification mark of the cast to which it applies, corresponding to the number or identification mark to be found on theSHISHUPASL SINGH M.B.E.M, SCHOOL OF PLANNING AND ARCHITECTURE</p> <p>8</p> <p>SPECIFICATION OF REINFORCEMENT BARS</p> <p>material. 5.2.1.5</p> <p>Identification and Marking: o The manufacturer or supplier shall have ingots, billets and bars or bundles of bars marked in such a way that all finished bars can be trace to the cast from which they were made. Every facility shall be given to the purchaser or his authorized representative for tracing the bars to the cast from which they were made. o The medium tensile steel bars shall be suitably marked to identify them from mild steel bars. Mild steel bars Grade I and II shall have distinctive identification tags. o Each bundle or coil containing the bars may also be suitably marked with the Standard Mark, in which case the concerned test certificate shall also bear the Standard Mark.</p> <p>5.2.2 Independent Laboratory Test 5.2.2.1 Selection and Preparation of Test Samples: Unless otherwise specified in standard, the requirements of IS: 226-1675 shall apply. 5.2.2.2 All test pieces of bars shall be selected by the purchaser or his authorized representative, either: a) From the cutting of bars b) From any bar or the coil, after it has been cut to the required or specified length and the test piece taken from any part of it c) In neither case, the test piece shall be detached from the bar or the coil, except in the presence of the purchaser or his authorized representative. d) Before test pieces are selected, the manufacturer or supplier shall furnish the purchaser or his authorized representative with copies of the mill records g...</p>

Recommended

View more >