House Construction Cost Calculator Excel Sheet For Ground Floor(G.F.), G.F.+1, G.F.+2, G.F.+3, IS 516:1959 Most Important Point (Method of Tests For Strength of Concrete).
Hence approximate moment coefficient recommended in IS 456, which was derived through idealization done using a series of long strip, should be used to calculate moment and shear force. so, read it carefully to get full knowledge about it. All rights reserved. Determine the minimum thickness of slab from serviceability criteria of deflection control.As it is already discussed in preliminary design of slab, CLICK HERE to reach there. The factored bending moment can be calculated by using the coefficient of bending moment from table 26 of IS 456:2000. Created by. durable red and blonde quartzite sandstone in a variety of colors and shades including red, brown and rust. Check the thickness of slab.The thickness of slab is calculated for given value of factored moment then check with initial value. Check for development lengthFrom IS 456:2000 clause 26.2.1The development length is given byLd = 0.87 fy Փ / 4ႠbdStep 10. The area can be calculated from given formula; The spacing of main reinforcement bar should not be more than 3 times the effective depth of solid slabs or 300 mm whichever is smaller. And due to simplified assumption, the theoretical bending moment being greater than those actually realized.
Check for shearFor one-way slab, it would not be a bad practice to check for shear.From IS 456:2000 clause 40.2,The design shear strength Ⴀuv shall be less than equal to shear strength of concrete kႠuc. I started this site to spread knowledge about Civil Engineering. A brick wall of 250 mm thickness including plaster of 1.0m height is provided at the end of cantilever fc’ = 17.25 MPa, fy = 300 MPa, Slab thickness of room = 125 mm. Although slab is not casted in 1 m strip, it gives satisfactory design result on using 1 m strip. Created by. Your email address will not be published. The two way slab design is also designed as explained in IS codes. The basic difference are as follows: For the calculation of bending moment, the coefficient in table 27 of IS 456:2000 should be used. Select slab thickness to satisfy deflection and shear requirements. The prevention from lifting may be due to monolithic casting with beam or construction of partition wall on the support. Since load is distributed in both x and y direction, reinforcement have to be designed for both direction. Hey, I am Krunal Rajput.
Step 7. The thickness calculated from factored design moment should be less than initial value if not, revise with greater depth. Natural rock slabs perfect for landscape design. Difference Between 33, 43 and 53 Grade Cement, Difference Between Carpet Area and Built-up Area, Difference Between CPM and PERT/PERT Vs CPM, Difference Between Fat Lime and Hydraulic Lime, Difference Between Flexible Pavement and Rigid Pavement, Difference Between Footing and Foundation, Difference Between Lap Length and Development Length, Difference Between One Way Slab and Two Way Slab, Difference Between Plasticizer And Superplasticizer in Civil.
The thickness of steel reinforced slab typically between 100 and 500 mm thick. Step 5. It will be better to visit preliminary design of slab, which was discussed before in details. Center to center of supports or clear span + width of support. Unyielding support means supports with sufficient stiffness which may either beams or walls. ax and ay coefficient are obtained from IS 456 tables -26, fig 10.3 shoe nine separate possible arrangement for a two-way restrained slab. The service live load is 100 psf and 4000 psi concrete is specified for use with steel with a yield stress equal to 60000 psi. The area of reinforcement on each layer should be 3/4th of the area required for maximum bending moment at mid-span. Determine the total factored load due to live and dead load considering 1m wide strip.Dead load is calculated from IS 875 part 1 and it mainly includes self-weight, floor finish and partition load whereas live load is calculated from IS 875 part 2. If ratio of longer span to shorter span is less than 2, then it is two-way slab, otherwise one-way slab. Determine the area and spacing of main reinforcement.The area can be calculated from given formula;Mu = 0.87 fy As [ d – fy As/ fck b]The spacing of main reinforcement bar should not be more than 3 times the effective depth of solid slabs or 300 mm whichever is smaller.And the minimum area of main steel reinforcement is equal to 0.12% of bD.Step 8. Spacing should not exceed smaller these two values. And there is almost zero bending moment at the support so there is no need of top layer reinforcement. Determine the minimum thickness of slab from serviceability criteria of deflection control. Assume the thickness of slab (take 4 cm per metre run of the span). The reason for designing only for flexural member is that the shear stress are not critical and reinforcement provided for flexural is enough to resist. The frequent use of slab is found as floor and roof in building, decks in bridges, top and bottom of tanks, road pavement and so on. We help brands optimize their online presence & performance. Step 2. Your email address will not be published. Design Procedure :- Case I:- Corners are not prevented from lifting. At CivilJungle, we clarify civil engineering and publish all the happenings & news of civil engineering. 2.The span ratio ly/lx is less then or equal to 2 . I am a Degree Holder in Civil Engineering. Step 7.
The thickness initially obtained is through different assumption and after calculating area of reinforcement provided, it is easier to calculate exact modification value. It is not necessary to check for shear in two-way slab.
The two way and one way slab design are mainly focused.
Fy = 500 N/ Sq.mm —– Fs = 0.58 X 500 = 290 N/ sq.mm. Step 1. Hey, I am Krunal Rajput. Two way slabs are those slab which are supported on unyielding supports on all four sides and the ratio of longer span to shorter span is less than 2.
Stay connected to build dream building project. Analysis and Design of Slabs
One Way Slab Design Example: A reinforced concrete slab is built integrally with its supports and consists of equal span of 15 ft. Slabs are those structure which transfers dead load and lives load over large span or area to the beam and column also on the wall sometimes. There would be no torsion arises in this cases so it is not necessary to provide torsional bar in this case. Calculate the factored design moment Mu and factored design shear force Vu.It’s formula is already mentioned above for different conditions (simply supported, continuous,…)Step 6.
DESIGN AND ANALYSIS PROCEDURE- DIRECT DESIGN METHOD Operational Steps Figure 11.9 gives a logic flowchart for the following operational steps. Step 1. Only half of the torsional reinforcement required at the corner of adjacent discontinuous edge should be provided at corner of only one discontinuous edge. Aspect ratio is the ratio of effective longer span to shorter span. Restrained slab simply means the slab which is supported on four sides with corner held down or the slab whose corners are prevented from lifting. Step 5. Your email address will not be published. If there is no restraint at the discontinuous support, the negative moment developed is equal to zero. After designing all, all reinforcement drawing should be drawn. Simply supported:The maximum bending moment is at mid-span equal to wl²/8The maximum shear force is at support equal to wl/2The maximum deflection is at mid-span equal to 5wl⁴/ 384EI, Fixed slabThe sagging moment at the mid-span is wl²/24 and hogging moment at support is wl²/12.The maximum shear force is at support, equal to wl/2The maximum deflection is at mid-span, equal to wl⁴/ 3.84EI, Cantilever slabThe maximum bending moment is at mid-span, equal to wl²/2The maximum shear force is at support, equal to wlThe maximum deflection is at mid-span, equal to wl⁴/ 8EI.
2020 Civil Construction. The distribution reinforcement is provided despite it does not contribute on load transfer. Design a cantilever projecting out from a room slab extending 1.0m and to be used as balcony (LL = 300 kg/m2). Here we only talk about uniformly distributed load. I am a Degree Holder in Civil Engineering. Share it with your friends! Whichever is smaller ——– as per IS 456-2000 P. 34, CI 22.2.a, For Fe-250 Pt = 0.15 % of total C/s area (d x D), For Fe-415 Pt = 0.12 % of total C/s area (d x D), For Fe-500 Pt = 0.12 % of total C/s area (d x D) ——– as per IS 456-2000 P. 48, CI 26.5.2.1. Step 9. Step 9. The thickness of slab is calculated for given value of factored moment then check with initial value.
Slab is a common structural element consisting of a flat, horizontal surface with depth much smaller than width and span. But it may be necessary in one way slab only if span is small and load is large. One way slab is the slab that is supported on two parallel sides carrying loads by flexural in the direction perpendicular to the support. The possibility of partial restraint must be considered, even if no restraint, at the time of detailing. Calculate the effective span of slab from IS 456 clause 22.2 which is least of following values. Fy = 250 N/ Sq.mm —– Fs = 0.58 X 250 = 145 N/ sq.mm.
Effective Depth (d) For deflection control L/d = 20 X M.F M.F. It consists of two layer; top and bottom layer and reinforcement in each layer is parallel to the span of slab.
Determine whether the slab is one-way or two-way slab by calculating aspect ratio. Calculate the distribution reinforcement.From IS 456:2000 clause 26.5.2.1; the distribution reinforcement should be provided 0.12% of b D if high strength deformed bar or 50% of main reinforcement whichever is greater.The spacing of distribution bar should not be greater than 5 times the effective thickness of slab or 450mm whichever is smaller.Step 12. Check the adequacy of depth from deflection control criteria. 22nd September 2020 by Krunal Rajput Leave a Comment, Fs = 0.58 Fy X (Ast requierd / Ast Provied), Initially assume that Ast reqierd = Ast Provided.
Check the adequacy of depth from deflection control criteria.The thickness initially obtained is through different assumption and after calculating area of reinforcement provided, it is easier to calculate exact modification value. 2020 Civil Construction. In restrained slab, torsional reinforcement should be provided. Concrete Slab Design Procedure. The factored shear force can be calculated by using the given formula: Vu = w (r⁴/(1+r⁴))* lx /2 where, lx is length of shorter span. Step 7.
Two-way slab:- A slab is considered two way slab if 1.Slab is supported on all four sides.
For the calculation of maximum bending moment, IS 456:2000 Table 26 and 27 gives the coefficient of bending moment at span and support for given condition of boundary and aspect ratio. It is advisable not to use slab of thickness greater than 150 mm in building because it increases the self-weight which causes severity in earthquake.
Your email address will not be published. Required fields are marked *. Fy = 415 N/ Sq.mm —– Fs = 0.58 X 415 = 240 N/ sq.mm. Determine the area and spacing of main reinforcement in both direction.
Nano Clone Vs Neo Clone, Hades And Persephone Play Script, Why Is Vascepa So Expensive, Groupme Messages Going To Text, Trevor Donovan Brother, Vrf Vs Split System Cost, Dark Line On Stomach Horizontal, Dave Hall Wanda Sykes, How To Tame A Strider, Potassium Bicarbonate Fungicide, Adrian Gonzalez Wife, Am I Too Old To Be A Wildland Firefighter, Funny Buffalo Names, Nginx Ingress Aws Annotations, Deadly Possessions Peggy The Doll, Wayne Grudem Net Worth, Bip Synonyme 3 Lettres, Trove Cheats Ps4, Manhunt: Unabomber Streaming Vf, Korean Goldfish Snack, Attracted To Someone Else While In A Relationship Reddit, Dollarama String Lights, Zoology Essay Questions, Airlander Stock Price, Helium And Nickel Are Examples Of, Is Gohan Stronger Than Vegeta In Super, Quiz Power Rangers Dino Charge, Pyt Football Break, Stan Shaw Net Worth, Wood Fired Pizza Van For Sale Uk,