300mm. 12% of high yield strength deformed bars. Spacing of 10mm bar = S1 =150 c/c. Side clear cover of slab 25 mm; Thickness of slab is. t + D Chair bar per square meter. 6. If the reinforcing bars do not extend beyond the critical section. Step 1. The distribution bars provide the following functions in slab construction: 1. 12% of the overall sectional area. 2. Most of these formulas are based on the analysis of results of tested beams or oneway slabs. The no. Larger areas, lower loads, and higher seismic zones. iv) Detrmine Sapcing of bars at critical section based on designed value of Ast by selecting appropriate bar dia. = 2sqm/1sqm = 2nos. 667’ x 40. 6 Live Load. Provided to resist the bending stress. According to direct design, the balanced load, W1, and the effective prestressing, F, in a one-way slab or the beam supports for one-way slabs can be computed as t _ 48kBW + 8k f (L (3) Wl — 1 + 48kB F, = 72BW L2 + 12 f t2 (4) t(1 + 48kB) where B is the moment coefficient, M = BWL2, depending on the slabDesign of 2 way slab as per IS code. 89m. . Factor affecting spacing of chair bars. 5 m. Whereas, Factored Load = 1. 7. Spacing should not exceed smaller these two values. Inclined length = 0. This is also. 1,2 and 3 B. This portion is coming at the top of the bottom main bar. 67 m, the slab depth for the voided slabs ranged from 10 inches to 16. 4. 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. The size and number of reinforcing bars must be chosen to (1) provide an area of reinforcement equal to or greater than the amount that is required, and (2) satisfy the minimum and maximum spacing requirements in ACI. On the bigger side, distribution bars are supplied, however, they will not assist in bearing any weight. 1 Overview 4-1 4. 18% of gross sectional area (B×D), taking B= 1m width of slab and D= overall depth including cover, then minimum reinforcement will be = 0. 3). 3) For distribution bars, the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is smaller. (c) Deep beams in accordance with 9. 960 x 16 =. 25 8 #5 12 6 6 2 4. Refer to Section 5. Bar Bending Schedule Of Slab (Two Way) Ly/Lx = Longer span/Shorter span = 5000/3000 = 1. 18% of gross sectional area (B×D), taking B= 1m width of slab and D= overall depth including cover, then minimum reinforcement will be = 0. ”Distribution bars are typically used in conjunction with main bars, and they are often spaced at regular intervals along the length of the main bar. 14 m, and 10. 3 introduces a new requirement for bar 1) The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. 6 For two‐way slabs, maximum spacing of bars shall not exceed two times the slab thickness h nor 450 mm. Important Points. 1. Clause 6. 2. Always main bar use in shorter span. Maximum size of bars in slabs As per clause 26. The direction of the main bars (T1 and B1) in a flat slab system depends on various design factors such as the span length, load distribution, structural efficiency, and code requirements. 21. 6. 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. C. To find the Bar Bending Schedule for Slab we use the following formula, No. 3. 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. 3. 4—Construction load distribution 3. 1. 6. 6. is more that the diameters used here. , see 10. The bigger span in the above slab, 5000, divided by the shorter span, 2000, is 2. 5. For ACI 318-08 and ACI 318-11 5. 12% of the gross cross-sectional area if HYSD bars (Fe 415) are used. joint spacing greater than 50 ft (15. 2 – Spacing of tendons shall not exceed 6 feet. 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. To distribute the superimposed load to the main bar. Business, Economics, and Finance. 12. 3. 1 of code IS 456:2000. Practical considerations of one-way slab • Spacing shall be between 150-200 mm (main bars) • Spacing shall be between 150-300 mm (distribution bars) • Max. 19 or greater, the minimum concrete cover is 5 cm. Cutting length= 9000 – 2 x 50 =8900 mm =8. Maximum spacing should not exceed the lesser of 20 x size of the smallest compression bar or the least lateral dimension of the column or 400 mm. 5, which is more than 2. The manual design process included the reinforcement calculation for the main bars and distribution bars as per the considerations and as per the problem statement. Thickness of Slab = 0. 4 times effective depthThe precast concrete product, which is used to provide the necessary covers or spacing for the reinforcement bars from the formwork, in all the RCC structures like slab, column, beam, footing, etc. Reinforce concrete for a 5-inch thick concrete slab: For a 5-inch thick slab, #4 (1/2-inch diameter) rebar is commonly used. 6. No of Bars/m 2 = Factored Load / Pcr. 2 and 9. Clear span of the two way slab = 5000 mm. 2 and 26. The. No. We would like to show you a description here but the site won’t allow us. Step 1- Calculation of Numbers of Bars. Eurocode 2 section 9. t 12mm stirrups at 150mm ctrs Two terminated bars A A Elevation Section A-A Lsy. Code of practice for plain and reinforced concrete ( third revision ) Specification for high strength deformed steel bars and wires for concrete reinforcement ( t&d revision ) Criteria for earthquake design of structures (fourth revision ). 1 of IS 456), the maximum spacing is the lesser of 3d and 300 mm i. Other notations, wherever used, areQuick guide to design of one way slab – with IS Code 456:2000. Main Bar. 2. t 12mm stirrups at 150mm ctrs Two terminated bars A A Elevation Section A-A Lsy. Distribution Bars are used to hold the slabs on either way and to resist the cracks. 3. 2. Solving for the Number of Reinforcement Chair required per square meter: Since the chair reinforcements support only the top layer, then we will consider the weight of top mesh reinforcement as dead load. 2. c) Slab reinforcement percentage less than 0. ' = 1536 sq mm. Maximum spacing of main bar is restricted to 3 times effective depth or 300 mm whichever is less. 2 or 8. 12. Rebar steel will be calculated for the bending moments “Mx” and “My. Step 2 – Calculation of Cutting Length. Common rebar sizes range from #3 to #6 for slab footings, with #4 being the most commonly used. stationary live loads less than 400 po unds per square foot. 5 m). Adopt a clear cover of 20 mm and 8 mm diameter bars. 2, The diameter of reinforcing bars shall not exceed one-eighth of the total thickness of the slab. 15% of the total cross-sectional area of the slab (bD). 2, 17. 3. 12D Sq. Two way slab building. ment among different types of cements. 002 times the gross cross-sectional area of the footing. 1. The clear cover is 30 mm ( top to bottom ) and the thickness of the slab is 150 mm. 2. C. 2. If the maximum diameter for slab thickness is 75 mm, so the diameter of reinforcing bars should be 8 mm. Maximum spacing of tension bars (all slabs) In accordance with clause 7. The minimum reinforcement spacing is based on maximum size of aggregates, so that concrete can be placed and compacted properly. Calculate cutting length: calculate the required number of bars for both directions. 5 inches, and the transverse bars must be fully developed in grouted masonry at the point where they cross the lapped reinforcement. 3. The distribution bars number 17 in total. 26. Now, we will calculate the length of the three parts of the chair bar separately. How to calculate reinforcement bar spacing How to calculate Minimum Bar Spacing for Bundle Bars in Cast-in Place Concrete as per AASHTO provisions. Number of Required Bars Formula = (Length of slab / spacing) + 1. Slab steel bar not less than 10mm dia. 13. What Is Bar Bending Schedule | Preparation as Per Bs 4466 | Tolerances as Per Bs 4466; Disadvantages of Dowel Bar. 11. Check for Cracking. 1. b) Slab depth does not exceed 200 mm when the steel grade is 460. 150m = 150 mm. 230/0. 1 Spacing s of longitudinal bars in cast-in-place walls shall not exceed the lesser of 3h and 18 inches. Area of One Bar 20114 Sqmm 16 RESULT Spacing of Distribution Bars 360 mm 16 from BSCE 11234 at Xavier University - Ateneo de CagayanThe maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. Roof drainage system (Adapted from the International Code Council). 3. Weight of rod per meter length = d 2 /162 where. Wood structural panels with a minimum thickness of 7 / 16 inch (11. of main bars = Lx/Spacing + 1 = 5000/150 = 34. 2). 3. No of main. 2R-8 4. 3 introduces a new requirement for barBridge Deck Slab Design Example as per IRC Indian Codes, Deck Slab Bridge Design are described step by step by Using Limit State Method. A minimum of three bars evenly placed in the lap length is required. 3 Direct supply of steel reinforcing bars to site by QA Manufacturer 27 Section 5 Purchasers testing 28 5. 4. 7. Step 1. One Way Slab Bar Bending Schedule Calculation. How to Design Concrete Structures to Eurocode 2 - Chapter 7 : Flat slabs and Figure 6. 6—Reinforcement limits 8. reinforcing parallel to load per inch of slab width perpendicular to load / slab thickness) (steel yield stress)) f. This type of reinforcement is convenient for modeling layers of reinforcement over a portion or the entire slab area. Number of Required Bars Formula = (Length of slab / spacing) + 1. 11. Lower part bar will be worked by maintaining cover with spacer. 3. 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. slabs) or integral with slab with depth greater of 2. Abstract. Spacing between bars = 0. 376Kgs For Floor slab -2 (One way slab) :-As per the above figure Floor slab -2 is a One way slab. 3 Required Strength 4-2. thick slab will increase the potential for random or out-of. VARIATION AMONG BETWEEN MAIN BARS AND DISTRIBUTION BARS: 1. 8. Generally # 3 or # 4 bars are used for slab main reinforcement. Step Find the length of the dowel bar embedded in slab by equating Eq. Load Calculation: Live Load = 2 kN/m 2. 26. For preparing the bar bending schedule according to the given data. 5bw and 600 mm B. The transverse bar must be No. 11. 0104 Ai. 1 Spread Box BeamsA. 75H for surcharged wall Base slab thickness= H/10 to H/14 Toe projection= (1/ 3-1/4) Base width Behaviour or structural action and design All the three elements namely stem, toe and heel acts as cantilever slabs and hence the design 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. The length of a distribution bar on the south side will be the same as the north side. 13. The diameter of the chair bar should not be less than 12 mm. >EAST side. Here, ∅ is the bar diameter. Important Point: As per IS 456:2000, the limit on minimum reinforcement along either direction has been specified. 18D sq. 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. 5. 2. 3. 11. Spacing of bar = area of a bar * width of strip / area of reinforcement required = 78. = 16 mm, spacing @ 150 c/c. Thus, the requirement threshold of 125psi (0. 6. Design a one-way slab having a simple span of 3 m. Number of bar =radius /spacing. 3) For distribution bars, the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is smaller. Calculate the quantity of. The ACI 318-19 provides a number of requirements regarding slab thickness, concrete cover, and reinforcement ratio which facilitate the design process. Spacing of Main reinforcement bars = s m = 150mm c/c. Thickness of the slab=l x /32= 98. M =. 14 x r x r) = 3. Maximum size of bars in slabs As per clause 26. Height of the footing (Thickness) = h =0. The Distribution bars will be 8 mm in diameter @125mm c/c spacing. 2. 8. 2. Calculation of number of distribution bars. For footings that exceed 8 inches (203 mm) in thickness, a minimum of one bar shall be provided at the top and bottom of the footing. It is appropriate to design the slab per unit width, hence b = 1000mm. The continuous vertical bar required beside an opening is permitted to substitute for one of the two No. Adequacy of curing. Such splices, where used, shall be welded, lapped or otherwise fully. Spacing of Main Reinforcement: The maximum spacing of bars shall not exceed. 2. The punching shear capacity is obtained via the ACI code equations, seen below. Top & bottom main bar dia. The Distribution bars will be 8 mm in diameter with 125 mm c/c spacing. 4 mm. 8. The length of a distribution bar in east side is, = (17′-1½″) + 2 × 10″ = 18. For main bars, maximum spacing is restricted to 3 times effective depth or 300 mm whichever is smaller. 4 must be met, and max. For longitudinal bars in slabs. 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. , Structural. The larger the diameter of the bar, the more the spacing is, and vice versa. 2, or >0. 7—Reinforcement detailing 8. SECTION 5: CONCRETE STRUCTURES 5-5. , the effective depth is: clear spacing between layers clear cover stirrup diameter bar diameters 2 dh . spacing of bars should not be more than. member :. c. The format for each example follows the format of the ACI Design Handbook, SP-17, and provides a reference to the Code paragraph for each calculation procedure. It is a useful reference for engineers, planners and contractors involved in bridge construction. For structural slabs of uniform thickness the minimum area of tensile reinforcement in the direction of the span is: For US-units: IF Grade 40 to 50 deformed bars are used. 10. t + DChair bars are used primarily on the slab and flooring. 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. 5. C. If a closer spacing of bars is required at the columns, as per Section 13. 9. 15% of the gross cross-sectional area if. 3d or 300 mm whichever is smaller for main steel. Design the slab using the data given below; Purpose of building – Residential. where a is the radius of the wheel load distribution in cm and h is the slab thickness in cm. 1 QA Stockist’s certification of steel reinforcing bars 25 4. slab should not exceed three times the effective depth of the slab or 450 mm whichever is smaller. 3 of the Eurocode or Chapter 2, originally published as. 3) or the breadth ofthe rectangular beam or slab or the breadth of the rib in case of flanged beam (ci. 96 x 1000 / 1536 = 130. 7. In ACI 350R-89, the recommended minimum S&T reinforcement for walls with movement joint spacing greater than 60 ft (18. According to ACI Code 7. 54 * 1000 / 180 = 436. So No, of 8 mm Steel bar = 3. 75 Nos. In RC slabs and PT one-way slabs, the clear distance between bars is limited to the smaller of. a) Slab depth does not exceed 250mm when the steel grade is 250. As per clause 26. 785 x 16^2 = 200. Full bond Full bond h/2 Filler Figure 15:3: Contraction joint 15. 4. The depth of voided slabs could reduce the height of the structural system up to one foot per floor compared. Minimum number of reinforcing bars required. Since diameter of bar = 10 mm. Distribution Bar. 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. 3. Dia of Distribution Bar=16mm. In ACI 350R-89, the recommended minimum S&T reinforcement for walls with movement joint spacing greater than 60 ft (18. 1 Purchaser’s tests of steel reinforcing bars 28 Section 6 Methods of testing 32 6. 7. 1 - 10mm Ø vert. 1 or the bottom bars required by 8. It brings economy to the design of. Tech. Calculated area; 5 x d; 450mm; Diameter of bars. 2 Specific requirements for QA Stockists 26 4. Distribution bar = 8mm@150mm c/c. 1905. 1. 0m from the fixed end. Use #4 bars at 25-inch spacings center to center each way, As = 0. Leg of Chair= (2 * spacing of bottom main bar) + 50Plain 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. 6. MOM-X – Longitudinal moment, corresponding to which LONG. 17 x 10 6 )/ (1000 x 119 2 x 25) = 0. 3. For a 6 in. Slab Thickness = 150 mm. According to Clauses 8. 8. Area of reinforcement per metre width of spacing. Height of block wall = 2. Step 4 – Extra Top Bar. L 1 = (2 x spacing of distribution bar) + (2 x the clear cover). 1 or the bottom bars required by 8. a = axial spacing of the bar for calculating the lap length (ci. 24 SOLID SLABS 24. 8. Weight of the bar as per their length and diameter by following the Formula: –. Considering M20 grade of concrete and Fe 500 steel of diameter of 10 mm. of chair bars = Area of structural reinforcement in sqm / chair bar per sqm. f ck = 25 Mpa. 2. 5 m as per IRC. slabs, walls, and joists - #14 and #18 bars - ½ inch; Slabs, walls, and joists - #11 bars and smaller - ¾ inch ; Beams and columns. Weight of Distribution Bar= d²/162. Note: The minimum clear spacing of bars is not kept less than 75 mm (Preferably 100 mm) though code do not recommend any value. 15m. 1. 5 bars required by 14. bars in two-way slabs. However, it is not a code, so many engineers do use portions of ACI 318 on their projects. The “D” bars shown in the tables conform to Article 9. three times the effective depth of solid slab or; 300 mm; whichever is smaller. The Main bars will be 12 mm in diameter with 100 mm c/c spacing. 9, page 341. 5. Consider 28 Nos. steel bar use Top Side +28 Nos Steel use. 6H to 0. 3. 1. Grade of concrete ƒck, Grade of Steel ƒy, Concrete cover, Clear long spam, Clear short spam, With of supporting beam, Live load, Floor finish load, The diameter of the main and distribution bar, and; Assume the. 11in2) Spacing = As 0. This chapter shall apply to the design of nonprestressed and prestressed beams, including: (a) Composite beams of concrete elements constructed in separate placements but connected so that all elements resist loads as a unit. C.