Opposite length of bar = 2950. Eurocode 2 section 9. For basic building the 4 number of bars is sufficient as per code. Total Length of Distribution Bars = 19. exposed to earth or weather. 13. C. 3. 3 b) 1). Weight of Main Bar = (102/163) x 126. 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. 3 of IS 456) 20 KTUNOTES. The maximum spacing of reinforcement at critical design sections for positive and negative moments in both the middle and column strips shall not exceed two times the slab thickness (ACI Code Section 13. 1 Purchaser’s tests of steel reinforcing bars 28 Section 6 Methods of testing 32 6. 667’ x 40. 3—Corner restraint in slabsColumn = Self Weight x Number of floors. Given the radius of relative stiffness of 90 cm. 1. 2 – Spacing of tendons shall not exceed 6 feet. for. 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. Fig. The shear resistance in a R. 50 8. 5d = 5 * 130 = 650 mm. 26. 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. 4 Minimum Eccentricity Step 5: Calculation of Steel Weight. As per IS 456: 2000, Cl. Wood structural panels with a minimum thickness of 7 / 16 inch (11. 4 bars in the middle third of the footing depth. Figure 3:. How to calculate bar Bending Schedule for Slab? One way slab Reinforcement Detailing. the total length of the leg is 2×spacing +50. Adopt a clear cover of 20 mm and 8 mm diameter bars. 12. For slabs less than 200 mm thick the following maximum spacing rules apply: For the principal reinforcement: 3h but not more than 400 mm. Proportioning of flat slabs: As per cl. The continuous vertical bar required beside an opening is permitted to substitute for one of the two No. 9) Prepare bar bending. . Calculation of effective depth. of Main bars = (Width of Slab/Spacing) + 1. 347. three times the effective depth of solid slab or; 300 mm; whichever is smaller. 5 times effective depth d. 3. 6. 5 bar is permitted to be located at either the top of the slab or bottom of the footing. 785 x 16^2 = 200. 2. , 300 mm. 8 ACI 318 , Section 17. 5. Top and bottom clear cover of slab is 20 mm. 1. 20 square inch (129 mm 2) in cross-sectional area shall be provided: 1. 7. each way at center of slab construction joint for same shall not be more than 3000mm apart. Dowel bars require care in placement to minimize. Number of bar = total width /spacing +1. 3. however with a maximum spacing of 4. 1—Reinforcement for shrinkage and temperature. So maximum diameter of reinforcement bar used in 5 inch (125mm) thick. slabs) or. e. 2, with “S” assumed to be equal to the length between negative moment design sections. , B. Note: The minimum clear spacing of bars is not kept less than 75 mm (Preferably 100 mm) though code do not recommend any. Minimum reinforcement is ensured in slab (in both directions) to take care of shrinkage, thermal movements and. 090 square inches per foot of slab width, required each way. For interior Spans: According to the code, the moments can be distributed according to factores shown in the figure: II. 3 Design of the slab (per meter strip) Bending moment on the slab is maximum at the face of the column (in this case at the face of the upstand beams) (clause 3. 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. 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. of chair bars = Area of structural reinforcement in sqm / chair bar per sqm. 00mm Pedestal Clear Cover (P, CL) : 50. The diameter of the chair bar should not be less than 12 mm. Larger areas, lower loads, and higher seismic zones. 2, 17. Slab Thickness = 150 mm. Modify ACI 318 Sections 17. member has shallow depth of less than 150 mm (ex. , if the upper bar of 16mm dia. Thickness of Slab = 0. The Clear cover will be 25 mm (Top or Bottom) and the thickness of the slab will be 150 mm. Diameter of a chair bar should not be less than 12mm. unless otherwise noted, all slabs on grade are to be reinforced with 10mm bars at 400mm o. Bar Spacing According to ACI Code 7. 4 and shall have a total area of not less than 0. Diameter of top and bottom distribution bars = 16 mm. The Indian Standard (IS) code for the preparation of steel bar bending schedules is IS 2502:1959. 1 or the bottom bars required by 8. 3. C slabs. Chair bar per square meter. 2 d t kips in. e. The depth of voided slabs could reduce the height of the structural system up to one foot per floor compared. 3. 6 𝑀𝑃𝑎. rahuledu said: as per IS 456:2000, chair shall be fixed 1 no in 1 Sq. Earth Pressure intensity (q) = N/A prov = (18765. 24. 8 ACI 318 , Section 17. 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. . About this chapter: Chapter 3 covers general regulations for plumbing installations. 2 Spacing s of transverse bars in precast walls shall not exceed the. tangential spacing of legs of links, st max. 5 bars required by 14. 4. For interior Spans: According to the code, the moments can be distributed according to factores shown in the figure: II. If redistribution is carried in design, the allowable max spacing needs to be reduced or relaxed as per table 15 of IS456. How to calculate reinforcement bar spacing How to calculate Minimum Bar Spacing for Bundle Bars in Cast-in Place Concrete as per AASHTO provisions. 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. For instance, the ACI 318-19 specifies minimum slab thickness that satisfies deflection. ,). There are no SHGC requirements in the Marine Zone. 18D sq. For concrete cast against and permanently. 3. 9. 3. 5 b w d): For longitudinal bars bent at 45 degrees, the second equation above is replaced by S max =3d/4The spacing of distribution bars having diameter 10 mm should be 9 inches to 12 inches center to center c/c. The clear cover is 30 mm ( top to bottom ) and the thickness of the slab is 150 mm. b. Design ProcedureAllowable clear spacing of bars = 3d = 3(170) = 510 mm Actual clear spacing = 300 – 10 = 290 mm < 3d → ok Figure 3. 9. Now assume diameter of bars and calculate spacing between bars. per 18-in. , addi-tional bonded shrinkage and temperature reinforcement conforming to 7. What should be maximum spacing of main and distribution bars in slab?We would like to show you a description here but the site won’t allow us. Weight of the bar as per their length and. (Main Bar & Distribution Bar Difference) Top and Bottom Clear Cover is 25 mm. Number of Distribution Bars = Lx / spacing + 1 = 3000/150 + 1 = 21 nos. 25 x 87. 305. The equivalent of closer-spaced, typical slab bars can be achievedf DESIGN of ONE-WAY SLAB based on NSCP 2015 and ACI 318-14. 1 given below by the ACI 318-14 code. 4. The maximum spacing of reinforcement in slabs is 3d or 300mm(minimum of both). Type and spacing of the control and construction joints. Height of block wall = 2. Every alternate bar is cranked up to 0. 3. 10. 5 bar or two No. i = 100-yr. For slabs 200 mm thick or greater, the bar size and spacing should be limited to control the crack width and reference should be made to Section 7. Thickness of the slab=l x /32= 98. Always main bar use in shorter span. 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 maximum anchor nominal diameter is 5 / 8 inch (16 mm). Distribution of Main Bars. Height of block wall = 2. 2 of IS 456 :2000 , the reinforcing bars shall not exceed 1/8 of theHow to Design Concrete Structures to Eurocode 2 - Chapter 7 : Flat slabs and Figure 6. ' = 1536 sq mm. 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. 18% for higher concrete grades. Spacing of bar = area of a bar * width of strip / area of reinforcement required = 78. The maximum spacing should be reduced by a factor of 0. 2. Development length = 40d. , i. On the bigger side, distribution bars are supplied, however, they will not assist in bearing any weight. 1. 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. ACI 318-19, Table 8. Now, we will calculate the length of the three parts of the chair bar separately. 2) For main bars, maximum spacing is restricted to 3 times effective depth or 300. , addi-tional bonded shrinkage and temperature reinforcement conforming to 7. Spacing required = Area of 1 bar x 1000 / (Ast req. Calculation of no of bars required in slab reinforcement Number of bars = length of lab/spacing +1. equal to ( C < 2. 2(5)In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. No. For distribution bars, the maximum spacing is specified as 5 times the effective depth. Q) Calculate the quantity and weight of steel rod in a one-way slab having length 6 m, width 2. 7. Maximum diameter of the bars (cl. Tech. 2. 26. 1 of IS 456), the maximum spacing is the lesser of 3d and 300 mm i. 6. Concentrated reinforcement is a fixed number of bars over a parallelogram area. 3. 5. For a given area of tension steel areas, the distribution of steel reinforcement affects. 5h ≤ 450mm (in areas of concentrated loads 3h ≤ 400mm) Where h is the. 3 m) is either 0. 67’ Weight of Distribution Bars = d 2 /52. bars in two-way slabs. You can design the two way slab using our android application. 2. C. 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. 2. Placed at a shorter span. Distribution Bars= (Total length of the slab – 2 x clear cover)/center to center spacing of the bars + 1; Distribution Bars = (2000- 2 x 25) /125 +1; Distribution Bars = 16. The cross‐sectional area of one N28 bar is As = 620 mm2 and with N12 stirrups at 150 mm centres, Atr = 110 mm2. 6 𝑀𝑃𝑎. The ACI 318-19 provides a number of requirements regarding slab thickness, concrete cover, and reinforcement ratio which facilitate the design process. e. 67 m, the slab depth for the voided slabs ranged from 10 inches to 16. 8. The maximum spacing between stirrups is smallest of the following provided that (V s <0. to carry a uniform live load of 7500 Pa. the quality and basic shape of reinforcement bar shall be specified. Check for the depth. vapor retarders - some times referred to as vapor barriers, insulation, etc. 3 Slenderness Limits for Columns 25. Main Steel – 3d or 300 mm whichever is smaller; Distribution Reinforcement for Concrete Slab Design: The area of distribution reinforcement shall not be less than 0. 6666666667 = 21 nos No of bars = 21nos . Step Find the length of the dowel bar embedded in slab by equating Eq. 2 or 8. 3(1) of IS 456, is the lesser of 3(135) and 300 mm. Waist slab Bar Bending Schedule. Note: The minimum clear spacing of bars is not kept less than 75 mm (Preferably 100 mm) though code do not recommend any value. 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. NOTE 3 - In co1 3. 5. 4 Slabs Spanning in Two Directions at RightAngles 24. 3 Aggregates 5. bending dimensions shall be measured as shown for appropriate standard shapes. 2. The reinforcing bars must extend into the slab beyond the critical section for a required length. unless otherwise noted in plans or specifications, camber all r. In slabs constructed with lift-slab methods where it is impractical to pass the tendons required by 8. (14) Step Find the load transfer capacities , , and of single dowel bar with the. Total Length of Distribution Bars = 786. 1 or the bottom bars required by 8. Given Data: Height of footing = 600 mm. assume corners are held down. Having <0. 1. 1 or the bottom bars required by 8. 1 for minimum thickness of non-prestressed two-way slabs without interior beams is revised to include Grade 550. 1. 5. Reinforcement Cover The minimum cover to outside of main bars shall not be less than the following: 15 mm and; Diameter of the main bar. f. 1 Cement 5. 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. For longitudinal reinforcement in beams. >EAST side. Head of Chair: Length of head = (2 * spacing of distribution bar) + (2 * 50) = (2 * 150) + (2 * 50) = 400mm. 3. A cantilever slab 200 mm thick is 1. 1. Ensure a minimum number of bars in a square column is 4 and in a circular column, 6. Concrete cover = 25 mm. 3 only and there is no need to perform specific checks on the bar spacings to control cracking. 10 the minimum bar spacing for bundled bars shall be calculated based on the derived diameter instead of calculating from individual. Business, Economics, and Finance. = 175 mm Last perimeter, from column face, min. If a closer spacing of bars is required at the columns, as per Section 13. For preparing the bar bending schedule according to the given data. Whereas, Factored Load = 1. 4. 133 square inches per foot). Common rebar sizes range from #3 to #6 for slab footings, with #4 being the most commonly used. 2 m), regardless of steel grade. 1. 1. f. 3d or 300 mm whichever is smaller for main steel. Number of bar = 1. 3% (100As/bd < 0. FAQ . 7. The transverse bar must be No. And, in compression zone, same as in (a) above. Important Points. Bar Spacing. 89 M. If a closer spacing of bars is required at the columns, as per Section 13. 8. 12 x 100cm x D cm=0. Distribution Bar = 10 mm, Spacing – 150 mm c/c, Alternate bent up. 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. Distribution Bar. 1. IN Downloaded from Ktunotes. Also useful for attaching stirrup bar effectively. Check resistance to moment transfer from column to slab . Chapter 9 which is also per mitted per ACI 349-06 Appendix D. No of bars = (opp length/spacing) + 1. In ACI 350R-89, the recommended minimum S&T reinforcement for walls with movement joint spacing greater than 60 ft (18. total angular change of tendon profile from tendon jacking end to point under considerations, radians. Assume 𝑓𝑐′ = 27. For distribution bars the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is less. 2. Unit weight of concrete = 25 kN/m 3. 6. C. 1 General== a 1 in direction of 11 • = a, in direction of 12 • angle between the axis of a strut and the bars in the i-th layer of reinforcement crossing that strut. Anchor bolts are embedded into concrete a minimum of 7 inches (178 mm). 5 times the diameter of the longitudinal barR4405. B. iv) Detrmine Sapcing of bars at critical section based on designed value of Ast by selecting appropriate bar dia. 12% of high yield strength deformed bars. 1: The prime functional requirement of a joint is to cater for movements with very low resistance or with no resistance at all. Curtailment of bars in slabs Curtailment of bars is. Since diameter of bar = 10 mm. 5 M from the edge of wall and at both ends 6 mm plain M. 2. 1. 6. Generally, a #4 (1/2″) diameter reinforcing bar with a minimum grade of 40 is used for standard residential slabs. 2) b = edge distane of bar for calculation of lap length (cl. 3. Reading time: 2 minutes. thick slab, the maximum joint spacing should be limited to 12 to 15 ft. 6. a) Slab depth does not exceed 250mm when the steel grade is 250. t + D Chair bar per square meter. Distribution Reinforcement for Stairs. One Way Slab Bar Bending Schedule Calculation. M o can be distributed, according to factors given in the table 8. Number of Main Bars = (Length of Longer Side / Spacing) + 1 = (6000/150)+1. 7. Maximum spacing of main bar is restricted to 3 times effective depth or 300 mm whichever is less. 9) Check for shear ( using Table 19 of code IS 456:2000). 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. 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. 5% or 0. 1. Placed at a longer. Main Bars and Distribution Bars in Slab and Their Function. TWO WAY SLAB DESIGN SPREADSHEET:Fig 10: Reinforcement of a slab. Actual variety of 1 sides rebar =Number of main bar – rebar of the middle. 1. The thickness of Slab – 150 mm. So we have total 16 nos of distribution Reinforcement bar so the total length is. 12. BS EN 1992-1-1 Annex 1 1. 4. The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. 3. Cutting Length: = total length — 2 x clear cover = 4000 - 2 x 20 = 3960 mm or 3. Distribution bars are placed on the top of the. e. The diameter of the chair bar = d =12mm. MOM-X – Longitudinal moment, corresponding to which LONG. As many of these requirements would need to be repeated in Chapters 3 through 14, placing such requirements in only one location eliminates code development coordination issues associated with the same requirement in multiple locations. 25 x total length of bar. 6—Reinforcement limits 8. àIn case the thickness of slab is 120mm, the height of bent bar should be 60mm. 2 times effective depth b. 5 m. 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. According to ACI Code. 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. For ASTM A 497 deformed welded wire fabric Values in the subgrade drag equationData of Calculate Steel in Rcc Slab-. 7. 54 * 1000 / 180 = 436. Check for Cracking. 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 318-14, Building Code Requirements for Structural Concrete and Commentary. 7. 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. Total length = 3. 5—Application of the simplified method 3. In this article, we will develop a Slab Design Example using the last version of ACI-318-19: “Building Code Requirements for Structural Concrete,” consisting of the modeling in SkyCiv of a Reinforced Concrete Low-Rise Building focusing on the comparison of software results and hand calculations by an accepted method by ACI: “The Direct Design Method for. 6. 34 kg ——– (1) Section 1 Total = 33. Figure: Contraction joint;. The diameter of the main bar is 12 mm in diameter with 100 mm c/c spacing and the diameter of the distribution bar is 8 mm with 130mm c/c spacing. 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 ). are called concrete. The no. 3. 7 For temperature steel only, maximum spacing shall not exceed five times the slab thickness h nor 450. 2 and 9. Ensure that the return bars at the edge of the slab are a minimum of ¼ (15%) of the length of the adjoining span. bars are used as distribution bars and are placed at 30 cm centres at the top of the bottom bars. Thickness of Slab – 150 mm. Radius = 2. Radius =length /2. 4. Development length =40d . 2R-8 4. Reinforcement chairs should be made with a minimum of 12 mm bar. TRANS REINF - Reinforcement required along the transverse direction ( along local Y axis of the plates ). Depth of footing = 750 mm. 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. Weight of Distribution Bar=64/162. 12% of cross-sectional area as distribution rebars as per. Is 1200 Important Point Part-1; IS Code for Civil Engineer [Q&a]. AASHTO 5. Minimum spacing for distribution bars is, (1) 5d = 5 X 76 = 380 mm (2) 450 mm . t 12mm stirrups at 150mm ctrs Two terminated bars A A Elevation Section A-A Lsy.