Note * Spacing rationalised to suit punching shear links. spacing of bar/prestressing strand etc. Refer to Section 5. 12 x 100cm x D cm=0. , B. Top & bottom clear cover = 50 mm. Design the slab using the data given below; Purpose of building – Residential. , 300 mm. 7. Modify ACI 318 Sections 17. Note: The minimum clear spacing of bars is not kept less than 75 mm (Preferably 100 mm) though code do not recommend any value. 096 square inches per foot (or #4 bars at 18 inches center to center to meet ACI criteria, As = 0. 1 or the bottom bars required by 8. bars at every 3 layers of chb finished surface wall intersection b h lintel beam reinf. Number of bar = total width /spacing +1. (ii) The pitch of the bars provided to act as distribution bars or bars provided to guard against temperature and shrinkage in an R. 2 Minimum Slab Thickness 4-1 4. #IS456Explanation#SpacingofReinforcement#IESGATEWizIn this Video Part-45,detailed discussion of IS 456-2000 provisions of Spacing of Reinforcement Bars ha. 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. b) Slab depth does not. Weight of Distribution Bar=64/162. 1. Abstract. The thickness of Slab – 150 mm. member has shallow depth of less than 200 mm (ex. 2, 17. 2 mm. 6. 5. Calculation of effective depth. The minimum spacing between the two bars can be about 50–75 mm. NOTATION All notations and definitions are the same as defined in Chapter 2 of the Code. Transverse joint spacing should not exceed 125% to 150% of the longitudinal joint spacing. 4 bars in the middle third of the footing depth. Here we have to calculate the number of main bar and distribution bar. Provide a thickness of D=120 mm. 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. This reinforcement is reported in terms of area required per unit width of slab. 12D Sq. 1. , if the upper bar of 16mm dia. Diameter of top and bottom distribution bars = 16 mm. , addi-tional bonded shrinkage and temperature reinforcement conforming to 7. t + d Lsy. continuous slab – code coefficients-. 4H to 0. 60. Lesser dimension bars are used. 090 square inches per foot of slab width, required each way. 7. The clear cover will be 25 mm(Top or Bottom) and the thickness of the slab is 150 mm. 8. Ex. The distribution bars should be (2000- 2 x 25) /125 + 1. 6. Development length = 40d. Weight of the bar as per their length and. C. Current recommended. Special surface finishes, including coatings. i,e. Sub-slab details (i. 60 kN/m. c. Design Guide on the ACI 318 Building Code Requirements for Structural Concrete. Two-Way. Exceeding a joint spacing of 15 ft. Flexural tension reinforcement shall not be terminated in a tension zone unless (a), (b), or (c) is satisfied: (a) Vu ≤ (2/3)ϕVn at the cutoff point. REINF is calculated. k = (5. 2. There are 51 nos of main bars are required for the slab. Distribution bars are provided perpendicularly with the top of the main bar. 5 bars required by 14. 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. 3—Corner restraint in slabsColumn = Self Weight x Number of floors. 4. For a given area of tension steel areas, the distribution of steel reinforcement affects. 751. The cross‐sectional area of one N28 bar is As = 620 mm2 and with N12 stirrups at 150 mm centres, Atr = 110 mm2. 04𝑚𝑚2 𝑎𝑏 113. slab should not exceed three times the effective depth of the slab or 450 mm whichever is smaller. 2. 4. The no. Spacing required = Area of 1 bar x 1000 / (Ast req. 285+150. 3. Calculation of number of distribution bars. L is the required length of the Steel bar of Diameter D. EXAMPLE: Suppose we have a one-way slab, which has a length of 5 m or a width of 2 m (clear span). 2, 17. 26. 00mm Bottom Footing Clear Cover (F, CL). 5. 6% of the gross wall area for Grade 60 or Grade 40 bars, respectively. 26. 2. 9. for. 1. A review of the behaviour and design of different types of beam-column joints in reinforced concrete moment resisting frame under seismic loading illustrates that design and detailing provisions for the joints in the current Indian seismic code, IS 13920 : 1993. , and dowel length to be 18 in. Thickness of Slab = 0. 3. R-5 insulation shall be provided under the full slab area of a heated slab in addition to the required slab edge insulation R-value for slabs. 12. As per IS 456 : 2000, Minimum percentage of reinforcement: 0. For eg. 42D) – (1d x 4) – (2d x 2 (From BBS shape codes) d = diameter of the bar. No. The spacing of distribution bar should not be greater than 5 times the effective thickness of slab or 450mm whichever is smaller. Lower part bar will be worked by maintaining cover with spacer. 2. 667’ x 40. Section 8. e min = (L/500) + (D/30) ≥ 20 mm. cm. For distribution bars the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is less. 13. normally lower dia rebar tends to more sagging while placing in top layer. Where a slab on ground is cast monolithically with the footing, one No. IN Downloaded from Ktunotes. LL = 6. c. bars at every 3 layers of chb finished surface corner wall detail 1 - 10mm Ø vert. Area of Steel 'Ast req. 26. 1. , Chapter 12 c c = clear cover of reinforcement, in. Calculation of no of bars required in slab reinforcement Number of bars = length of lab/spacing +1. Distribution Bar. 1. The spacing of the bars The length of a distribution bar on the south side will be the same as the north side. Note that required A s must be furnished in each direction. According to it, if a slab rests on its support freely, the span length may be taken as equal to the clear span plus the depth of the slab but need not exceed the distance between the centers of supports. 5, which is more than 2. In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. For columns exposed to weather or contact with the ground and embedded bars are No. 6. Provided to resist the shear stress and cracks. Radius = 2. BBS of One Way Slab. Provided to resist the bending stress. For longitudinal bars in slabs. If the maximum diameter for slab thickness is 75 mm, so the diameter of reinforcing bars should be 8 mm. Distribution Reinforcement for Stairs. AS3600-2009 P P Lsy. 24. Some discussion to decide about max spacing: AS per IS 456: Maximum spacing for bars in beams is 180mm for Fe415 grade and 150mm for Fe 500 grade reinf. 4. Main Steel – 3d or 300 mm whichever is smaller; Distribution Reinforcement for. 67’ Weight of Distribution Bars = d 2 /52. 3. Design of the footing cantilever slab portion (per meter strip) Note that the bending moment in the slab is maximum. 97 kN/m 2. 1 of IS 456:2000, the reinforcement in either direction ,in slabs shall not be less than 0. i = 100-yr. 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. 7. 785 x d^2 = 0. 1. In Flat plate slab the, distribution bars are arranged in one direction at Top of main bar (in longer span). Exceptions: 1. 2 to read as follows:In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. Lesser dimension bars are used. C. 66 < 2. 1905. 3m. 230/0. The spacing of distribution bar should not be greater than 5 times the effective thickness of slab or 450mm whichever is smaller. 1. 4 bar at the top and the bottom. Sub-Grade and. 305. 11. No. 3 Direct supply of steel reinforcing bars to site by QA Manufacturer 27 Section 5 Purchasers testing 28 5. 2(5)In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. 4—Construction load distribution 3. 18/100× × 100× D = 0. 2. Distribution bars are provided in the longer span direction. Spacing of Main Reinforcement: The maximum spacing of bars shall not exceed. 76 Slab designation: CS1 Check if one-way or two-way slab 1 Slab is one way since it is catilever slab Minimum slab thickness min t = 69. In design of slab, as per IS-456, what should be minimum percent of distribution steel if Fe 415 reinforcement is used ? The minimum percentage of reinforcement is 0. BS EN 1992–1–1 section 6. The slab is supported all around walls of width 300 mm. 3 Slabs-on-ground with turned-down footings. Cutting length of main bar = Clear span of slab + (2 x development length) + Inclined length – (Bend length) Clear span of slab = 2000 mmFor one way slab, distribution bars are required to tighten the main bars together – since it has only one spanning reinforcement. 8. This change affects the calculation of minimum slab thickness for fy exceeding Grade 420. Placed at a longer span. 6% of the gross wall area for Grade 60 or Grade 40 bars, respectively. For a 6 in. According to ACI Code 7. S. 7—Post-tensioning load redistribution Chapter 4—Strength adequacy of concrete slabs and formwork, p. 150m = 150 mm. 2—Flexural reinforcement spacing 8. 75 m. Area of reinforcement per metre width of spacing. 24 SOLID SLABS 24. Such splices, where used, shall be welded, lapped or otherwise fully. of chair bars = Area of structural reinforcement in sqm / chair bar per sqm. 10m , Depth of Slab = 0. 04𝑥1000 𝑆= = = 272. c. 5. No of Bars/m 2 = Factored Load / Pcr. 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. Maximum spacing between Individual Bars: The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. The design of a one-way slab can be done by using the Indian standard code. Concrete moisture conditions and drying rate. BS EN 1992-1-1 Annex 1 1. 2 or 8. That is 11′. Factor affecting spacing of chair bars. According to ACI Code. Step 1- Calculation of Numbers of Bars. Effective depth=d provided =120-20-4= 96 mm. 26. 960 x 16 =. The. How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started. iv) Detrmine Sapcing of bars at critical section based on designed value of Ast by selecting appropriate bar dia. Reinforcement details bay C-D, 1-2. Temperature distribution due to heat of hydration and internal stresses caused by outside cooling in a free standing concrete block. total angular change of tendon profile from tendon jacking end to point under considerations, radians. 7. member has shallow depth of less than 150 mm (ex. 14 m, and 10. Bars shall not be smaller than No. 1% of the slab cross-sectional area) through sawcut contraction joints in combination with the recommended joint spacing. Dia of Main Bar=16mm. Head ( E ): The length of the head = [(2nos. Distribution Reinforcement bar: No of bars = total span/spacing = 2960 mm/200 mm = 15. 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. for industrial slabs that carry distribution. Modify ACI 318 Sections 17. In this article I will explain you complete slab design as per IS 456 code by using manual method. 7—Reinforcement detailing 8. 7. 25 x total length of bar. Roof drainage system (Adapted from the International Code Council). 5. 6. 2. correct. Maximum spacing of bars for slabs • Main bars: 3h ≤ 400mm (in areas of concentrated loads 2h ≤ 250mm) • Secondary bars: 3. No. The Distribution bars will be 8 mm in diameter with 125 mm c/c spacing. 9, page 341. 4 and shall have a total area of not less than 0. e. There is two spacing between 3 reinforcement and 50 mm length both side of 1st and 3rd reinforcement used in footing. 2 or 8. 2 mm. Calculation: The spacing of replaced bar is calculated by the formula [(D1) ² (D2) ²] = [S1 S2] Where,We would like to show you a description here but the site won’t allow us. Adopt a clear cover of 20 mm and 8 mm diameter bars. . How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started. 5 and 6. Dia of Distribution Bar=16mm. 5 m as per IRC. 3 Slabs-on-ground with turned-down footings. 1123 mm. 5 bar is permitted to be located at either the top of the slab or bottom of the footing. 15% of the total cross-sectional area of the slab (bD). 4: Two-way slabs having multiple spans; The purpose of the code is to design the total amount of reinforcement steel rebar into principal directions in the slab system. critical section of the slab is just outside the outside edge of the beam supporting the slab. 6H, and 0. Check for Cracking. The slab is not. and : 1786-19667, the nominal size of the deformed bar is equivalent to the diameter or side of a plain bar having the same weight per metre run as the deformed bar. Rebar steel will be calculated for the bending moments “Mx” and “My. 11. 6 𝑀𝑃𝑎. 2. 1 given below. Earth Pressure intensity (q) = N/A prov = (18765. 12% of high yield strength deformed bars. If it is desired to replace 10 mm bars by 12 mm bars, then the spacing of 12 mm bars should be. 5. ,). Total length of Foundation Distribution bar =No’s of bar x cutting length. Cutting Length: = total length — 2 x clear cover = 4000 - 2 x 20 = 3960 mm or 3. Loads which consist of any on e of the following: moving live loads exceeding a. GameStop Moderna Pfizer Johnson & Johnson AstraZeneca Walgreens Best Buy Novavax SpaceX Tesla. for interior walls. 1. 1 of EC2, the recommended minimum spacing of reinforcing bars is 75 mm and 100 mm for laps. In case of HYSD bars, minimum reinforcement along either direction shall not be. 6. 4. Calculation of number of distribution bars. 3 Dowel bars The purpose of the dowel bar is to e ectively transfer the load between two concrete slabs and to keep the two slabs in same height. 2 shall be provided between the ten-dons at slab edges extending from the slab edge for a dis-tance equal to the tendon spacing. Special surface finishes, including coatings. 2, also includes guidance on achieving enhanced aggregate interlock by continuing a small percentage of deformed reinforcement (0. 4 Splices in reinforcement. Considering M20 grade of concrete and Fe 500 steel of diameter of 10 mm. 4. D. 2R-8 4. 3 Slenderness Limits for Columns 25. Main Steel – 3d or 300 mm whichever is smaller. 8. The use of #4 or #5 bars is at the discretion of the Structural Project Manager if both available diameters meet demand. Practical considerations of one-way slab • Spacing shall be between 150-200 mm (main bars) • Spacing shall be between 150-300 mm (distribution bars)Bar Bending Schedule for Two Way Slab. 5 bar or two No. Design procedure. Length of the Slab = 5 m = 5000 mm. Since diameter of bar = 10 mm. As the slab is inflexibly fixed at the ends, this shrinkage will be limited by the support, which will prompt liable tensile stress in the slab. Generally # 3 or # 4 bars are used for slab main reinforcement. 3 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall ‘be rounded off in accord-Table 5. 5 m). stationary live loads less than 400 po unds per square foot. 1. For distribution bars (cl. 62 m, 9. however with a maximum spacing of 4. 2. If a closer spacing of bars is required at the columns, as per Section 13. Spacing =80mm. 12% Gross area for HYSD bars, 0. 300 Area of bars Φ12, a=π62 = 113. This type of reinforcement is convenient for modeling layers of reinforcement over a portion or the entire slab area. steel bars. the value of the calculated k is far below the limiting k’ for slabs. 2 to read as follows:Historically, this level of precompression was found to enhance the performance of punching shear in two-way flat slabs based on tests conducted with this level of precompression. of Main bars = (Width of Slab/Spacing) + 1. 15% for Mild steel bars. The main bars will be 12 mm in diameter @100 mm c/c spacing. One Way Slab Bar Bending Schedule Calculation. 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. Step 2: Calculate cutting length of main bars and distribution bars. Minimum number of bars for a square column are 4 and for circular column are 6. the maximum spacing between two secondary parallel bars in case of RCC Slab shall be 5d or 450 mm or whichever is less. 26. Given the radius of relative stiffness of 90 cm. Distribution Bar. 230m. Minimum spacing for distribution bars is, (1) 5d = 5 X 76 = 380 mm (2) 450 mm . 10. 15% of the gross cross-sectional area if. equal to ( C < 2. In this kind of.