What is the maximum spacing of bars in slab? What Is The Maximum Bar Spacing In Slab As Per IS-Code? In the case of the RCC slab, the maximum spacing between the two parallel main reinforcement bars should be 3D or 300 mm or whatever. Bar cranking is the process of bending up the bottom steel bars in upward direction. 15=7no’s. No. Bars of distribution equal 16. Nos of Bars =. 8 say 16 nos. 2 Use Φ12 bar c/c 250mm 2. 78′ Say, 19′ >WEST side. >EAST side. The length of a distribution bar in west side is the same as the east side. About this chapter: Chapter 3 covers general regulations for plumbing installations. 3(d) and 17. EXAMPLE PROBLEM 1. 1 Conditions of test specimens 32ACPA Guide Specification | Dowel Bars for Concrete Street and Highway Pavement | ACPA M254-21a August 1, 2021 | Page 4 of 12 2. a) Slab depth does not exceed 250mm when the steel grade is 250. of chair bars = Area of structural reinforcement in sqm / chair bar per sqm. 2 m), regardless of steel grade. No of Bars/m 2 = Factored Load / Pcr. 5:3) 2) centering and shuttering for slab 3) Weight of 12mm Φ bars 4) Weight of 6 mm Φ distribution steel bars 5) Abstract for approximate estimate 6) Cement, sand, Aggregate for slab 7) Percentage steel in slab 8) Cost of slab per m. 3. >EAST side. No Of Bars Required For Cutting Distribution Bars. In Flat plate slab the, distribution bars are arranged in one direction at Top of main bar (in longer span). The Main. This type of reinforcement is convenient for modeling layers of reinforcement over a portion or the entire slab area. 20 square inch (129 mm 2) in cross-sectional area shall be provided: 1. Check resistance to moment transfer from column to slab . The spacing of the chair bars depends on several factors which are listed below: – Diameter of the bar used in making a chair. Step 5 – Calculation of Steel Weight. and 𝑓𝑦 = 276 𝑀𝑃𝑎 for main and temperature bars. Check spacing of bars. IS 456: 2000 CONTENTS PAGE SECTION 1 GENERAL J SCOPE 2 REFERBNCES 3 TERMINOLOGY 4 SVMBOU SECTION 2 MATERIALS, WORKMANSHIP, INSPECTION ANDTESTING 5 MATERIALS 5. , Structural. If a closer spacing of bars is required at the columns, as per Section 13. Maximum Reinforcement Ratio:In this video, you will learn the Spacing between the Main and Distribution steel bar. 5h ≤ 450mm (in areas of concentrated loads 3h ≤ 400mm) Where h is the thickness of. 2 to read as follows:Top & bottom distribution bar dia. For interior Spans: According to the code, the moments can be distributed according to factores shown in the figure: II. per 1 m 2. Thickness of Slab = 0. 6. 5. 3) or the distance of centre of gravity of the concentrated load from the nearer support (ci. 3. 36 Live load Canopy = 1. Given, Length of longer span = 5000 mm. 2. Difference Between Main Bars And Distribution Bars: Main reinforcement bar is normally used at the bottom of the slab. (c) Distribution. For ASTM A 497 deformed welded wire fabric Values in the subgrade drag equationData of Calculate Steel in Rcc Slab-. Wall Load Per Running Meter. Modify ACI 318 Sections 17. 2. 4. 3. Minimum Reinforcement Ratio in Uniform Footing. 1 General 24. 3(1) of EC2 for slabs not exceeding 200mm in overall depth and not subjected to significant axial tension the maximum limit on centre to centre bar spacing is governed by clause 9. , see 10. Ex. The distribution bars are arranged to retain the mesh in perfect place and sustain the center to center c/c, bars. Load Distribution. Exceeding a joint spacing of 15 ft. Radius =length /2. The no. 11. 2) The horizontal distance between parallel reinforcement bars provided against shrinkage and temperature shall not be more thanACI 360R-102 is a major resource covering design of slabs-on-ground. from deviations in bar spacing and bar size are shown in figure 5. Now, we will calculate the length of the three parts of the chair bar separately. 17 x 10 6 )/ (1000 x 119 2 x 25) = 0. Learn More Estimate this Slab (Drawing Included) STEP 5. In this article I will explain you complete slab design as per IS 456 code by using manual method. steel bar on top of wall. 2. Minimum Bar Size : 16 mm Maximum Bar Size : 25 mm Top Footing Minimum Bar Size : 16 mm Top Footing Maximum Bar Size : 25 mm Pedestal Minimum Bar Size : 16 mm Pedestal Maximum Bar Size : 25 mm Minimum Bar Spacing : 100. 8. = 16mm, spacing @ 150 c/c. 2 of IS 456) shall not exceed 140/8 = 17 mm is also satisfied with the bar diameters selected here. bar. 24. b) In partially prestressed superstructure: In tension zone it shall not be less than that calculated as per Sections 12 and/or 16 (whichever is higher) of IRC:112. Reading time: 2 minutes. 3 of the Eurocode or Chapter 2, originally published as. for interior walls. 3 ANALYSIS 3. , Chapter 12 c c = clear cover of reinforcement, in. 1. This reinforcement is reported in terms of area required per unit width of slab. According to ACI Code 7. The thickness of Slab – 150 mm. ' = 1536 sq mm. (Rebar Calculation Formula) No. 8 ACI 318 , Section 17. Distribution bars of diameter 12 mm and center to center spacing 150 mmm. However, it is not a code, so many engineers do use portions of ACI 318 on their projects. Given data: Distribution bar dia. Now. The span requirement for the slabs is given by ACI Code 8. The maximum anchor nominal diameter is 5 / 8 inch (16 mm). Maximum size of bars in slabs As per clause 26. 2 SlabsContinuous OverSupports 24. The Main bars will be 12 mm in diameter with 100 mm c/c spacing. 3. length of dowel bar and a maximum joint opening of 0. 3. 2. slabs is Thickness of slab/8 14. C. 2 or 8. slab should not exceed three times the effective depth of the slab or 450 mm whichever is smaller. Main Bar = 12 mm, Spacing – 150 mm c/c, Alternate bent up. 2 (6) Beams: the maximum longitudinal spacing between shear assemblies s l,max; 9. Mainly used in slab and footing, it is the most significant part of raft foundation. , 0. Spacing of bar = area of a bar * width of strip / area of reinforcement required = 78. The quandary with composite slab roofs is that a composite slab provides higher shear strength, but it also adds mass to the system thereby increasing seismic forces. Calculation of effective depth. (Main Bar & Distribution Bar Difference) Top and Bottom Clear Cover is 25 mm. Suppose we have a one way slab,which having a length 5 m or width 2 m (clear span). 2. (i) The pitch of the main tensile bars in R. 5—Application of the simplified method 3. M =. 2. 8. The minimum yield stress of main reinforcement bars and shear links in the structural elements forming the SS, S/C SS or scissor S/C SS or NS shall be minimum 500 N/mm2. 25 in. 2(5)In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. In this article I will explain you complete slab design as per IS 456 code by using manual method. 5db). For Edge Spans : Static Mom. Calculate The Cutting Length of the Chairs Bar Given Data. . 3 – When spacing of tendons exceeds 54 in. The reinforcing bars must extend into the slab beyond the critical section for a required length. 3 Slabs-on-ground with turned-down footings. 13. 24 SOLID SLABS 24. Step 1. Workmanship and jobsite conditions. Type and spacing of the control and construction joints. Important Point: As per IS 456:2000, the limit on minimum reinforcement along either direction has been specified. 1 given below by the ACI 318-14 code. to carry a uniform live load of 7500 Pa. 6. 3. There are 51 nos of main bars are required for the slab. 40 cm;. 7. 3) For distribution bars, the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is smaller. 6. In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. 2. 6. Roof drainage system (Adapted from the International Code Council). 10. In case of mild steel, minimum reinforcement along either direction shall not be less than 0. Mild reinforcing bars shall have minimum clear spacing of at least 2 in. Design procedure. 150m = 150 mm. Minimum number of reinforcing bars required. Spacing = 150mm c/c as per given details = (2950/150) + 1 = 20. Other Standards ACPA T 253-21 Standard Method of Test for Dowel Bars for Concrete Pavement AWWA C213-07 Fusion-Bonded Epoxy Coating for Interior and Exterior of Steel Water Pipeline (American Water Works. 2 of IS 456 :2000 , the reinforcing bars shall not exceed 1/8 of theThe minimum size and grade of rebar for slabs depends on a variety of factors, such as the thickness of the slab, the loads it supports, seismic requirements and other factors. 2. Provided to resist the shear stress and cracks. , addi-tional bonded shrinkage and temperature reinforcement conforming to 7. 1. 96 sq mm. Only 2. 0018. C. 3. 4 mm. Max. . Spacing (feet) Deck Slab Thickness, T (inches) Transverse Bar Size and Maximum Bar Spacing, S (inches) F dimension (inches) #5 “D” Bars per Bay (quantity) #4 “G” Bars per Bay (quantity) Bar Size S 4. No. Use #4 bars at 25-inch spacings center to center each way, As = 0. 54 * 1000 / 180 = 436. 1 given below. 4. 5 mm 2. Provided to resist the bending stress. 1 Definitions 25. (b) For No. Base slab width b= 0. 2) For main bars, maximum spacing is restricted to 3 times effective depth or 300 mm whichever is smaller. The spacing of the bars The length of a distribution bar on the south side will be the same as the north side. 2: Alternate method for showing two-way slab reinforcement reinforcing bars should be clearly scheduled on the drawings. How do bars spread out on slabs according to IS-Code & IF Code? The spacing between the parallel main reinforced bars for RCC is 300 mm (3D). How to calculate reinforcement bar spacing How to calculate Minimum Bar Spacing for Bundle Bars in Cast-in Place Concrete as per AASHTO provisions. 11 bars and smaller, continuing reinforcement provides double the area required for flexure at. 14 x 5 x 5 = 78. 4H to 0. If the reinforcing bars do not extend beyond the critical section. The size and type of rebar used in concrete slab footings will depend on the specific requirements of your project, including the size of the slab, the load it will support, and local building codes. 6. 1 of IS 456), the maximum spacing is the. Step 2: Calculation of cutting length ( for main bars and distribution bars) Cutting length of main bar = Clear span of slab + (2 × Development Length) ( 2 × D e v e l o p m e n t L e n g t h) + Inclined Length - Bend Length. c) Slab reinforcement percentage less than 0. 10mm Ø hor. 5h ≤ 450mm (in areas of concentrated loads 3h ≤ 400mm) Where h is the. 3 times effective depth c. Having <0. TRANS REINF - Reinforcement required along the transverse direction ( along local Y axis of the plates ). 2. Minimum number of bars. 3. 4—Openings in slab systems 8. A minimum of three bars evenly placed in the lap length is required. Minimum area of slab reinforcement. 6. 26. 2. The distribution bars are arranged to retain the mesh in exact location and keep the center to center c/c, bars spacing among main bars. 3. 3). 13. 785 x 16^2 = 200. 5. Total length of bar required for distribution bars of Floor Slab 1 = 131m. 5. And, in compression zone, same as in (a) above. 26. 1—General 8. 4 Splices in reinforcement. According to ACI Code 7. To distribute the superimposed load to the main bar. cm. bars in two-way slabs. 304. Always main bar use in shorter span. As per clause 26. The maximum spacing should be reduced by a factor of 0. For the cranked bars near the supports at the top of the slab distribution bars of same size and same spacing are provided below the top bars. For distribution bars, the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is smaller. And depth of check is determined as per IS 456 standards. a) Slab depth does not exceed 250mm when the steel grade is 250. 6 in the following cases; In sections within a distance equal to 4 × thickness of wall above or below a beam or slab. The minimum percentage of reinforcement is 0. Diameter of the Main reinforcement bars = d m = 12mm. What is the maximum spacing of bars in a flat slab? The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. 54 * 1000 / 180 = 436. b) For design of distribution bar/Transverse bar. Distribution bars placed on top of the main bar. How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started. Before calculating the cutting length, we need to calculate each part length of chair bar. 6. Concrete cover = 25 mm. The code makes it explicit that the diameters of the skin bars are not involved in determining the spacing of this reinforcement. 1 mm) and maximum panel span of 8 feet (2438 mm) shall be permitted for opening protection in buildings with a mean roof height of 33 feet (10 058 mm) or less that are classified as a Group R-3 or R-4 occupancy. We would like to show you a description here but the site won’t allow us. 1 — Area of shrinkage and temperature reinforcement shall provide at least the following ratios of reinforcement area to gross concrete area, but not less than 0. 096 square inches per foot (or #4 bars at 18 inches center to center to meet ACI criteria, As = 0. Sketch the detail of reinforcement. Plain bars———–10 mm Ø min dia Deformed bars—–8 mm Ø min dia; For Distribution bars: Plain bars———–6 mm Ø min dia Deformed bars—–6 mm Ø min dia; 4. 4. 2. 3. length of. Cranking is also used in two way slabs. Total No’s of Distribution Bars = (Total layers of Dist Bars in Walls are 4) = 10 x 4 = 40 No’s Total Length of Distribution Bars = Cut Length x No’s of Bars. It is appropriate to design the slab per unit width, hence b = 1000mm. Distribution Bar = width of the foundation – 2 CC ÷ Spacing +1. Dowel bars are typically placed at the mid-depth of the slab and should be parallel to the pavement surface and parallel to the direction of travel. The spacing shall be less than five times the slab’s adequate depth, or 450 mm in the distribution bars. Total No’s of Distribution Bars = (Total layers of Dist Bars in Walls are 4) = 10 x 4 = 40 No’s Total Length of Distribution Bars = Cut Length x No’s of Bars. The complete calculation for one way slab is explained in the below steps. 12% of high yield. d = Effective depth. 3% (100As/bd < 0. 2—Construction load factorsThe diameter of the main bar should not be less than 8mm for the HYSD bar and 10mm for plain bars. Calculated area; 5 x d; 450mm; Diameter of bars. 1% steel allows sawed contraction. Providing 20mm diameter bars @130mm spacing C/C. 25 x 87 =34. M. The spacing of the lateral ties is 100mm to 200mm for safe structure design. Eurocode 2 section 9. 18/100× × 100× D = 0. 3. Design the slab using the data given below; Purpose of building – Residential. Ensure a minimum number of bars in a square column is 4 and in a circular column, 6. Minimum number of reinforcing bars. 1—Early-age concrete material strength development 4. TWO WAY SLAB DESIGN SPREADSHEET:Fig 10: Reinforcement of a slab. 5 The lateral spacing of temperature and shrinkage reinforcement should not be placed farther apart than 5 times the slab thickness or 18 inches according to ACI code 7. Maximum spacing between Individual Bars: The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. 3. , the effective depth is: clear spacing between layers clear cover stirrup diameter bar diameters 2 dh . 04𝑚𝑚2 𝑎𝑏 113. Number of Distribution Bars = Lx / spacing + 1 = 3000/150 + 1 = 21 nos. 133 square inches per foot). Bar Spacing. Joist system relative dimensions, slab thickness, rib width and spacing between ribs are specified in ACI 318-05, Section 8. Basically slab is the horizontal member which is rests on the beam section. To calculate: Spacing of replaced 12mm. In Seismic Design Categories D 0, D 1 and D 2, slabs-on-ground cast monolithically with turned-down footings shall have not fewer than one No. Figure: Contraction joint;. (1) Deformed steel bars will be overlapped for a distance of at least 24 bar diameters measured from the tip of one bar to the tip of the other bar. 67 m, the slab depth for the voided slabs ranged from 10 inches to 16. On the bigger side, distribution bars are supplied, however, they will not assist in bearing any weight. The code requires this value to be the minimum of these three values. 4—Construction load distribution 3. 2, also includes guidance on achieving enhanced aggregate interlock by continuing a small percentage of deformed reinforcement (0. member has shallow depth of less than 150 mm (ex. ACI 7. 11. 7. 15% of the gross cross-sectional area if. 21Two-Way Slabs 6 b- Distribution of the total factored static moment to negative and positive moments: I. 751. 9. Is 1200 Important Point Part-1; IS Code for Civil Engineer [Q&a]. 3. Now. 3. Weight of the bar as per their length and diameter by following the Formula: –. Concentrated reinforcement is a fixed number of bars over a parallelogram area. Step 4 – Extra Top Bar. Provided spacings, therefore, satisfy the requirements. Length of the Slab = 5 m = 5000 mm. e. The distribution bars should not be under 8 mm in a diameter or not be over 1/8 of the thickness of the R. 1 Purchaser’s tests of steel reinforcing bars 28 Section 6 Methods of testing 32 6. Number of bar = 1. Bar crank. Main Steel – 3d or 300 mm whichever is smaller. No. (a) for a distance equal to the larger lateral dimension of the column above and below a beam or slab, andvii) Any other function assigned to the expansion joint as per the specific requirements of the structural systems. This is plotted against the overall fire rating of the structure that is being designed. 1-4. Compute number of steel bars. As per ACI Code, In slab, minimum reinforcement shall be 0. 8. f. No. S. where a is the radius of the wheel load distribution in cm and h is the slab thickness in cm. Spacing of 10mm bar = S1 =150 c/c. 7. 4 Water 5. 6. For distribution bars the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is less. 19. 1. Rebar steel will be calculated for the bending moments “Mx” and “My. 12% of the gross cross-sectional area if HYSD bars (Fe 415) are used. For longitudinal reinforcement in columns of size 200 mm and less, with 12 mm diameter bars as longitudinal steel. Calculation for distribution bar: Bending moment for distribution. Number of Required Bars Formula = (Length of slab / spacing) + 1. The Clear.