Minimum reinforcement is ensured in slab (in both directions) to take care of shrinkage, thermal movements and. steel bar use Top Side +28 Nos Steel use. Weight of Distribution Bar for Waist Slab. No. The maximum clear spacing between parallel bars shall not be more than 1 N-6O. BBS of One Way Slab. It is mainly to prevent upward bending moment near the joint. 785 x 16^2 = 200. 230m. (15) Step Spacing of the dowel bars. The Clear. 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. 5. 12% of high yield. 3-Main bar Bottom Area Given data. The distribution bars provide the following functions in slab construction: 1. 2 SOLID SLABS SPANNING IN TWO DIRECTIONS When a slab is supported on all four of it sides it effectively spans in both directions, and it is sometimes more economical to design. 8. 200= 6. 1. Distribution bar 8 mm C/C 140 mm Length 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. Minimum Reinforcement Ratio in Slabs. 10. , Chapter 12 c c = clear cover of reinforcement, in. Design size and spacing of dowel bars at an expansion joint of concrete pavement of thickness 20 cm. Learn More Estimate this Slab (Drawing Included) STEP 5. The spacing of the lateral ties is 100mm to 200mm for safe structure design. 2 Specific requirements for QA Stockists 26 4. For main bars, maximum spacing is restricted to 3 times effective depth or 300 mm whichever is smaller. 11. 97 kN/m 2. No. f d n §· ¨¸ ¨¸ ©¹ ©¹ Since the required nominal moment from Section 1 (M n,reqThe Chinese code “Code for composite slabs design and construction” (CECS273:2010) states [34] that steel-bars truss can work with concrete as upper and lower bearing reinforcement in concrete, but without considering the role of steel-bars truss as a whole and bottom PSS, the bearing capacity of SBTS is calculated according to ordinary. àIn case the thickness of slab is 120mm, the height of bent bar should be 60mm. , and if the lap length is taken as 50d, then. BS EN 1992-1-1 Annex 1 1. 715m long, and it is supporting a blockwork load at 1. 2. 10. Calculation of number of distribution bars. Here we have to calculate the number of main bar and distribution bar. 5 bar or two No. to carry a uniform live load of 7500 Pa. e. 3 through the column, at least two post-tensioned tendons or two bonded bottom bars or wires in each direction shall pass through the lifting collar as close to the column as practicable. Head ( E ): The length of the head = [(2nos. 3. 1. 7. k = (5. rainfall intensity in inches per hour for the building location specified in the plumbing code. 1. the value of the calculated k is far below the limiting k’ for slabs. c 0. HYSD bars for upto M45 grade concrete and 0. The Main bars will be 12 mm in diameter with 100 mm c/c spacing. 12% of the gross cross-sectional area if HYSD bars (Fe 415) are used. For columns exposed to weather or contact with the ground and embedded bars are No. , 300 mm. Cranking is also used in two way slabs. Design the slab using the data given below; Purpose of building – Residential. The maximum spacing of main bars, as given in cl. 1—Early-age concrete material strength development 4. Here, ∅ is the bar diameter. 1 of EC2, the recommended minimum spacing of reinforcing bars is 75 mm and 100 mm for laps. Type and spacing of the control and construction joints. 167, hence it is singly reinforced. The maximum spacing of bars shall not exceed. 090 square inches per foot of slab width, required each way. 1. 3 of IS 456) 20 KTUNOTES. equal to ( C < 2. Total Load on Slab (Dead Load + Live Load +Wind Load + Self-Weight) Besides this above loading, the columns are also subjected to bending moments that have to be considered in the final design. The size of the stirrups should be chosen to avoid a closer spacing. 00mm Pedestal Clear Cover (P, CL) : 50. 25 8 #5 12 6 6 2 4. The minimum eccentricity values as per IS 456 code provision is calculated by using below formula in the column design we need to consider minimum or greater than 20 mm value as eccentricity value. 318-081, Section 7. However, in some cases, 10mm dia bars are taken for the floor slab, when there is no extra external load other than reinforcement mesh load. >EAST side. According to Clauses 8. 1 or the bottom bars required by 8. 5 Admixtures 5. = 2sqm/1sqm = 2nos. e. 12% of cross-sectional area as distribution rebars as per. Compute number of steel bars. Only 2. 2. Spacing of bar supports depends upon the size of the reinforcing bar being. 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. Provide main reinforcement of 10 mm diameter bars at 120 mm c/c. 5. 96 x 1000 / 1536 = 130. Anchor bolts are located a minimum of 1 3 / 4 inches (45 mm) from the edge of the concrete parallel to the length of the wood sill plate. Height of block wall = 2. slab, shall not. Main Bar. Reinforcement details bay C-D, 1-2. 14. Spacing of Main reinforcement bars = s m = 150mm c/c. Beams = Self Weight per running meter. Note * Spacing rationalised to suit punching shear links. Distribution bars are 8 mm in diameter @ 150 mm centre to centre spacing. 6. is the strength reduction factor as specified by table 21. 3. reinforcing parallel to load per inch of slab width perpendicular to load / slab thickness) (steel yield stress)) f. and 𝑓𝑦 = 276 𝑀𝑃𝑎 for main and temperature bars. 5. 2. 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. slab along the shorter span, 3mm per meter span. 4. 002 times the gross cross-sectional area of the footing. 3. Length of the Slab = 5 m = 5000 mm. 2). The diameter of the chair bar = d =12mm. 9) Check for shear ( using Table 19 of code IS 456:2000). 1000 1500 2000. 33=16 no’s. Minimum number of reinforcing bars. Load Distribution. TWO WAY SLAB DESIGN SPREADSHEET:Fig 10: Reinforcement of a slab. Distribution bars are provided perpendicularly with the top of the main bar. Q) Calculate the quantity and weight of steel rod in a one-way slab having length 6 m, width 2. Section 8. 7. 5. 6H, and 0. 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 bars required by 14. Tech degree in Civil Engineering with six specializations, i. 26. 3. Distribution Reinforcement) Class B (Not Top Bars) J, NThe span requirement for the slabs is given by ACI Code 8. Minimum S&T reinforcement quantities required by ACI 350-01 and11. Bar schedule for Slab; Table 3 : Bar schedule for SlabArea of single bar = (3. 6. 4. 4 bars in the middle third of the footing depth. Unit weight of concrete = 25 kN/m 3. In ACI 350R-89, the recommended minimum S&T reinforcement for walls with movement joint spacing greater than 60 ft (18. 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. The code itself suggests that the diameters can be #3, #4 and #5. 4 and shall have a total area of not less than 0. 8 ACI 318 , Section 17. 2, or >0. 2 Maximum Distance between Bars in Tension. 300mm. Check for Cracking. 3 only and there is no need to perform specific checks on the bar spacings to control cracking. 9 for flat slabs with drops. 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. Spacing s of longitudinal bars in precast walls shall not exceed the lesser of (a) and (b): (a) 5h. 12. tangential spacing of legs of links, st max. Main bar = 12mm@150mm c/c. 2) For main bars, maximum spacing is restricted to 3 times effective depth or 300 mm whichever is smaller. 3. As per ACI Code, In slab, minimum reinforcement shall be 0. How to calculate reinforcement bar spacing How to calculate Minimum Bar Spacing for Bundle Bars in Cast-in Place Concrete as per AASHTO provisions. 5h ≤ 450mm (in areas of concentrated loads 3h ≤ 400mm) Where h is the. Distribution bars are placed on the top of the. Modify ACI 318 Sections 17. Where a slab on ground is cast monolithically with the footing, one No. How to calculate bar Bending Schedule for Slab? One way slab Reinforcement Detailing. 26. Every alternate bar is cranked up to 0. 2. 1. Heavy loads. 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 ). t + d Lsy. 2 Maximum Distance between Bars in Tension. Conclusion. 11. =Eq. Spacing = 150mm c/c as per given details = (6000/150) + 1. 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. How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started. How do you calculate slab distribution bar? Formula = (total length – clear cover)/center to center spacing + 1 main bar, = (5000 – (25+25))/100 + 1, = 4950 divided by 100 + 1, = 51 bars. e. 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. 8. For ASTM A 497 deformed welded wire fabric Values in the subgrade drag equation Data of Calculate Steel in Rcc Slab-. Conclusion. Sawcut Joints A typical SOG includes three different types of joints, described in detail in ACI 360R Chapter 5. 10. The length of a distribution bar in east side is, = (17′-1½″) + 2 × 10″ = 18. BASIC THUMB RULE FOR RETAINING WALL DESIGN-Base slab thickness not less then 0 (H= Total height of retaining wall)The bottom part of the chair bar is called the leg of the chair bar. 24 SOLID SLABS 24. That is 11′. 4 must be met, and max. 3 m) is either 0. Particular care isIRC SP 066 : 2016 is a standard specification and code of practice for the design of steel pedestrian and cycle bridges in India. Spacing of Main Reinforcement: The maximum spacing of bars shall not exceed. Top & bottom clear cover = 50 mm. 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. In Flat plate slab the, distribution bars are arranged in one direction at Top of main bar (in longer span). However, it is not a code, so many engineers do use portions of ACI 318 on their projects. 2), The bar spacing shall not exceed 450 mm at any location (ACI Code Section 7. The spacing between longitudinal reinforcement of the column should be the greatest of the following: 4 cm; 1. Development length =40d . 1. Distribution Bar = 12 Number of The Distribution Bar. The clear cover is 30 mm ( top to bottom ) and the thickness of the slab is 150 mm. 1% of the slab cross-sectional area) through sawcut contraction joints in combination with the recommended joint spacing. 6. 1. is for dowel diameters to be one-eighth of slab thickness, dowel spacing to be 12 in. Distribution bars placed on top of the main bar. Total Length of Distribution Bars = 786. Diameter of top and bottom main bars = 20 mm. 5 bar is permitted to be located at either the top of the slab or bottom of the footing. 5 Loads on Supporting Beams 25 COMPRESSION MEMBERS 25. Rebar steel will be calculated for the bending moments “Mx” and “My. (i) The pitch of the main tensile bars in R. 2. the quality and basic shape of reinforcement bar shall be specified. 3) or the distance of centre of gravity of the concentrated load from the nearer support (ci. , 0. The number of bars is 50. bars in two-way slabs. This change affects the calculation of minimum slab thickness for fy exceeding Grade 420. 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. 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. c. Top & bottom main bar dia. deck slab and diaphragms, spliced girder system, precast pre-tensioned open or closed. Maximum spacing of bars for slabs • Main bars: 3h ≤ 400mm (in areas of concentrated loads 2h ≤ 250mm) • Secondary bars: 3. 2 For one-way shallow foundations, two-way isolated footings, or two-way combined. 1. 5. 40 cm;. The slab is not. 2. iv) Detrmine Sapcing of bars at critical section based on designed value of Ast by selecting appropriate bar dia. 3) For distribution bars, the maximum spacing is specified as 5 times the effective depth or 450 mm whichever is smaller. But even after that If d,provided < d,reqd, slab thickness is to be increased and check for deflection is to be satisfied. Tech. 150m = 150 mm. 7. how to calculate the number of rebar in an exceedingly circular block. Clear Cover = 20 mm. 5d or 450 mm whichever is smaller for distribution steel. 9. Total length of bar required for distribution bars of Floor Slab 1 = 131m. About this chapter: Chapter 3 covers general regulations for plumbing installations. 3. Cutting length= length of retaining wall – 2 x concrete cover. Now, we need to replace the distribution bar of 10mm. for. Figure: Contraction joint;. In this article I will explain you complete slab design as per IS 456 code by using manual method. C. 15%of gross cross-sectional area if plain bars are used and 0. 2, 17. Temperature distribution due to heat of hydration and internal stresses caused by outside cooling in a free standing concrete block. 5. 5bw and 600 mm B. Adequacy of curing. If the maximum diameter for slab thickness is 75 mm, so the diameter of reinforcing bars should be 8 mm. Question: Question 11 Not yet answered Marked out of 1. Longitudinal reinforcement should not be less than 0. Larger areas, lower loads, and higher seismic zones. Ensure that the return bars at the edge of the slab are a minimum of ¼ (15%) of the length of the adjoining span. In the. 140 M. If a closer spacing of bars is required at the columns, as per Section 13. 25 x 87. The Main. 34 kg ——– (1) Section 1 Total = 33. Bar Spacing. Bar cranking is the process of bending up the bottom steel bars in upward direction. VARIATION AMONG BETWEEN MAIN BARS AND DISTRIBUTION BARS: 1. Chapter 9 which is also per mitted per ACI 349-06 Appendix D. This is also. 1 and 24. slabs is Thickness of slab/8 14. of Main bars = (3000)/150 + 1. Step 2 – Calculation of Cutting Length. unless otherwise noted in plans or specifications, camber all r. (ii) The pitch of the bars provided to act as distribution bars or bars provided to guard against temperature and shrinkage in an R. 1 of IS 456), the maximum spacing is the. Fig. 8. ratio of flexural stiffuess. 1 Spread Box BeamsA. Clear span of the two way slab = 5000 mm. and 𝑓𝑦 = 276 𝑀𝑃𝑎 for main and temperature bars. 75H for surcharged wall. 27. 93 m 2 ) = 469. There are 51 nos of main bars are required for the slab. 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. Concrete cover to main reinforcing bars shall be provided per AASHTO Table 5. 1. Design a one-way slab having a simple span of 3 m. You just enter your information in the yellow colour box for the design of two way slab excel sheet as per is 456 such as. Lapping is not allowed for the bars having diameters more than 36 mm. This is plotted against the overall fire rating of the structure that is being designed. 6. 4 Deck Overhangs for guidance on deck slab bars. We would like to show you a description here but the site won’t allow us. Number of Main Bars = Ly / spacing + 1 = (4000/150) + 1 = 27 nos. Given, Length of longer span = 5000 mm. spacing of reinforcing bars (cls. 8 ACI 318 , Section 17. Weight of Distribution Bar=64/162. 7. 12% of the total cross sectional area , when HYSD bars Fe415 are used. 18D sq. L 1 = (2 x spacing of distribution bar) + (2 x the clear cover). s code Sandeep Yadav. Distribution steel: 0. 3. 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. The slab edge insulation for heated slabs shall not be required to extend below the slab. 2. 14 m, and 10. Fig. 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, the lateral spacing of the flexural bars should not exceed three times the thickness of 18 inches. The max. 3. Basically slab is the horizontal member which is rests on the beam section. 12. 3. C. 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. Suppose we have a one way slab,which having a length 5 m or width 2 m (clear span). 7. The distribution bars should not be under 8 mm in a diameter or not be over 1/8 of the thickness of the R. Mainly used in slab and footing, it is the most significant part of raft foundation. Number of bar = 1. 4—Openings in slab systems 8. The design of one-way slab is simple and can be carried out easily. bar due to its non-availability. Design ProcedureAllowable clear spacing of bars = 3d = 3(170) = 510 mm Actual clear spacing = 300 – 10 = 290 mm < 3d → ok Figure 3. 3. Weight of the bar as per their length and diameter by following the Formula: –. 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. 5. 3. Cover block use 15 to 20mm. design wheel load. Slab steel grid not less than Fe500. This smaller amount of reinforcement0. . dia. 1) The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. ACI 318-19, Table 8. 00mm Bottom Footing Clear Cover (F, CL). 3 of the Eurocode or Chapter 2, originally published as. however with a maximum spacing of 4. 15% of the total cross-sectional area of the slab (bD). According to ACI Code 7. Use #4 bars at 25-inch spacings center to center each way, As = 0. Bar Spacing According to ACI Code 7. e. 12. joint spacing greater than 50 ft (15.