Allowable deflection in slab

Allowable Deflection in Different Standards - Structural Guid

  1. L/360. Roof or floor construction supporting or attached to non-structural elements likely to be damaged by large deflections. That part of the total deflection that occurs after attachment of the non-structural elements (the sum of the long-term deflection due to all sustained loads and the immediate deflection due to any additional live load.***
  2. Allowable Deflections, consists of seven members with Russell S. Fling as chairman. the actual deflections and to place more realistic limits on the magnitude of these deflections. CHAPTER 2-COMPUTATION O·F DEFLECTIONS Strength computations are usually based on the assumption that the member will never (or on
  3. Construction Measures to Reduce Deflection Slabs C ure the concrete to decrease creep and shrinkage Build camber into the floor slab Materials Selection to Reduce Deflection of Beams and Slabs Use concrete with a higher modulus of rupture Use fibers to the concrete mixture Cure the concrete to allow.

What Is The Allowable Max Deflection In A Beam Column And Slab Quora Deflection Limit For Steel Beams Supporting Masonry Parions Structural Ering General Discussion Eng Endix A Sls Requirements In The Eurocode Bridges For Service Life Beyond 100 Years Limit State Design National Academies Pres So if you have a beam 20ft long, the allowable deflection limit is (20ftx12in/ft) /240 = 1 inch if using L/240. Or, (20ftx12in/ft)/360 = 0.67 inch if using L/360. This means that your actual calculated deflection of the beam should not exceed either 1 inch or 0.67 inch, depending on which of the criteria you are using

#048 Allowable maximum deflection in Beams and slab

Allowable Deflection Steel Beams Aisc - New Images Beam

What is the allowable max deflection in a beam, column

Deflection of Slabs - Structural Guid

  1. g floors
  2. The most common allowable are a tilt of 1% and a deflection of L/360. In other terms, a tilt of up to 1 inch in 100 inches and a deflection of 1 inch in a length of 360 inches are acceptable. The performance deflection criteria cannot be directly compared to the design deflection criteria of the foundation because th
  3. deflection in a bay is the sum of the deck, beam and girder deflections. Figure 3. Deflection during construction of composite slabs with 30-foot bays can double as a result of switching from A36 steel and Allowable Stress Design to Grade 50 steel and Load and Resistance Factor Design. Because of ponding deflection caused by wet concrete, the us

Maximum Deflections of Reinforced Concrete Beams and Slab

  1. Deflection limits for the composite deck are given in BS EN 1994-1-1 and BS5950-4. According to BS EN 1994-1-1, if the maximum deflection of the sheet is greater than 1/10 of the slab thickness, then ponding should be allowed for
  2. e the maximum allowable deflection in a bea
  3. the theoretical deflection can be assessed using the expressions given in the Code. The span-to-effective-depth (L/d) method. In simple terms, the current EN1992 L/d method means verifying that: Allowable L/d = N x K x F1 x F2 x F3 ≥ actual L/d. where. N =
  4. The equations which express the slab deflection limits presented in the previous section, are non-linear functions of the depth of the slab, h, the applied loads, g and q and the degree of prestress, k. Live load and prestressing degree values were imposed and the slab depth was obtained by solving the equations using the Newton-Raphson method.
  5. e the deflection of a reinforced concrete structure, which is then compared with a limiting value. According to clause 7.4.1(4) of EN 1992-1-1:2004 , the appearance of a structure (beam, slab, or cantilever ) may be impaired when the calculated sag exceeds span/250 under.
  6. Date: 1/1/1985. Abstract: A simple, design oriented procedure for the control of deflection in reinforced concrete slab systems is proposed. A rational and reliable expression for the maximum allowable span to depth ratio for beams, proposed recently by Rangan, is extended to the entire range of reinforced concrete flexural members including.
  7. Typical slab on beams design procedure long term deflection calculation robot structural ysis deflection limit for steel beams eurocode design factors and limitsWhat Is The Allowable Max Deflection In A Beam Column..

Checking slab deflection is included in the beam design section of BS 8110 Part 01. Deflection can be checked by two methods. If you know the maximum deflection for relevant load case, we can check whether it is with in the limit. Code gives the maximum limits of deflections base on the spans. Other method of check the deflection is that. My client has a problem with excessive deflection. A.: ACI 117 doesn't cover deflections of composite deck slabs. Section covers top-of-slab level alignment for cast-in-place concrete for buildings, allowing a tolerance of 3/4 inch on elevation of top surfaces of formed slabs before removal of supporting shores What Is The Allowable Max Deflection In A Beam Column And Slab Quora. Deflection Limits Of Steel Deck Structures Bs 5950 Code Structural Ering General Discussion Eng. A Cantilever Beam Is Subjected To The Point Load Chegg. Arch 331. Controlling The Deflection Of Steel Cantilever Beam Using Pre Tensioning Cable Slab deflection is a function of stiffness. The stiffer the slab, the harder it is to deform as per Newton's good old pal Hooke in what is known as Hooke's Law. (Historical trivia: there was an enmity between the two.) This stiffness is the interaction of tension and compression within the slab section during bending RE: Allowable Beam Deflection. BantrelStructural (Structural) 26 Nov 02 19:01. Also, something missed even by many experienced engineers, is that a deflection limit of l/360 (or any other span based limit) is not always the governing limitation. Intersecting structures, appurtenances, or equipment may impose stricter limits

slabs deflection. It has been found that most significant factor affecting deflection is the slab thickness. Keywords: Deflection, Eurocode2, Model, One -way slab. 1. INTRODUCTION Structural members must be designed to meet ultimate and serviceability limit state requirements to present adequate design with the best economical solutions 2-Allowable deflections (∆ allowable ) Studies have shown that excessive deflection in beams causes undesirable effects, such as cracked ceilings and floors as well as vibration. Building codes (IBC, 2008) typically specify the maximum allowable deflection so as to avoid these problems. The Maximum-actual deflections are compare - Deflections of two-way slab systems with and without beams, drop panels, and column capitals need not be computed when the minimum thickness requirements of 9.5.3 [Table 9.5(c)] are met. Deflection calculations are NEVER required - All code deflection criteria can be satisfied by providing minimum thicknesses

Deflections Many difficulties develop in buildings as the result of deflections of spanning members, which sometimes are in excess of those allowed for by designers. It is thought that excessive rotation at end joints, or differential deflections between slabs of precast materials can be the cause of roof membrane cracking in some cases Simplified Calculation of Short-Term Deflection in Prestressed Two-Way Flat Slabs. Panatchai Ch. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 37 Full PDFs related to this paper. Read Paper. Simplified Calculation of Short-Term Deflection in Prestressed Two-Way Flat Slabs. Download

Allowable Deflection

  1. computations of the total slab deflection for the different concrete strengths. Figure 5 shows the long-term deformed shape of the slab under the applied dead and live loads described previously. Table 2 shows comparisons of deflections calculated for slabs with 5000, 8000, and 10,000 psi concrete. The results are reported with a
  2. In modeling the project on ETABS I set the property modifiers for slab (thin shell as 0.25) and this affected the deflection in slabs ( about 5 cm deflection from service loads) Hence: Slab thickness is 22 cm and interior beams 50X50 and the owner didn't allowed to increase the thickness Any suggestions to solve the problem
  3. Deflections in slabs and beams. Deflections must always be considered in the design of slabs and beams. Both Eurocode 2 and BS 8110 include deemed-to-satisfy span-to-depth ratio methods for ensuring compliance with acceptance criteria. These rules will be perfectly adequate and provide economic solutions for the vast majority of designs
  4. imum slab, beam, column and wall sizes for fire rating allowed by the BCA and the Concrete Structures Code (AS 3600:2001) (Ref. 2); and; The

TM 5-809-1/AFM 88-3, Chap. 15 2-1 CHAPTER 2 BASIS OF FLOOR SLAB ON GRADE DESIGN 2-1. Stresses. thermal expansion and contraction of the concret The most economical design for a slab will depend on loading, layout, relative costs of materials etc., but in most cases slabs should be made as thin as the deflection limits allow. However if design rules allow excessive deflection, the result can be sagging floors, cracked partition walls and an unhappy building owner 3 CHAPTER 8b. SERVICEABILITY OF BEAMS AND ONE-WAY SLABS Slide No. 4 Long-Term Deflection ENCE 454 ©Assakkaf The total long-term deflection is given by ∆LT =∆L +λ∞∆D +λi∆LS (12) ∆LT = total long-term deflection ∆D = initial dead-load deflection ∆LS = initial sustained live-load deflection (a percentage of the immediate ∆L determined by expected duration o

Allowable Pressure for Gravity and Lateral Forces 2.600 psf [125 kN/m2] S.3 LOADS The loads on the podium slab consist of the weight of the superstructure; weight of the slab; and seismic/wind forces transferred from the superstructure to the slab. The load from the superstructure typically does not line up with the podium slab supports. It i Deflection of two way slabs is entirely different from one way slab or beams. Due to typical boundary conditions the deflection is less than the case of one way slab which deflect in cylindrical. The hollow-cored slab sections cho-sen were the 8 and 12-in. nonproprie-tary types from the PCI Design Hand-book.2 The shallowest depth hollow-cored slab was not chosen since it was felt that the shallower sections ap-proached the load-deflection behavior of solid slabs. The 8 and 12-in. sections were cho-sen to give deflection behavior peculia 4. For slabs, max. permissible deflection under all loads is Lx/350; for all loads excluding LL, it is Lx/250. Note that max. permissible deflections include long term effects. Indrajit Barua. From: santhosh reddy.s <forum@sefindia.org> Sent: Thu, 14 Jul 2011 17:18:32 To: general@sefindia.org Subject: [SEFI] MAXIMUM ALLOWABLE DEFLECTION FOR.

A NEW METHODOLOGY FOR THE CALCULATION OF LONG-TERM DEFLECTION OF SLABS WITH RIBS. In version 18.1 you can define a beam as a rib in your floor/slab system and the software itself calculates the accurate stiffness for the rib and the slab independently. Moreover, you obtain both the total deflection and the deflection due to creep at the same time Figure 9 - Load Vs deflection of filler slab (a) and the RC solid slab (b) for Series two . experiment . In above graphs, 'VALU' represents the . theoretical deflections are in allowable.

But before we proceed, let us first delimit our discussion to conventional reinforced concrete slabs (beam-slab or flat slab systems to be specific). Obviously, post-tensioned slab, composite construction, and proprietary slab systems such as hollow cores have different deflection mechanics compared to conventional ones The algorithm for deflections of RC slabs is based on the use of calculations of an isotropic elastic slab made of an elastic material. Changes of material stiffness due to cracking are considered. Displacements are calculated applying the Finite Element Method (FEM), then they are modified. Calculations are performed separately for each pane This paper presents an effort of doing an experiment to investigate the deflection behaviour and proposing charts for selecting the area of FRP for control the deflection of RC slab. The charts can help engineers to quickly estimate a proper area of FRP according to the allowable deflection and applied load. 2. Experimental Progra The guidelines include 2 quantitative standards: 1/360 for deflection, and 1% for tilt. The ASCE defines the deflection ratio as the maximum distance from a straight line, drawn between 2 points on a foundation and the surface of a foundation. When applied, the standard, taken in isolation, can mean that slopes in excess of 1 inch over a 15.

The American Architectural Manufacturers Association, aamanet.org, addresses this in its standard, AAMA TIR-11 Maximum Allowable Deflection of Framing Systems for Building Cladding Components at Design Wind Loads. AAMA TIR-11 establishes a deflection limit of L/175 for spans less than 13 feet 6 inches and L/240 + ¼ inch for spans greater than. Use M20 concrete. (a) check for deflection as per simplified procedure of IS 456:2000. (b) check for deflection if the slab is reinforced with 8mm bars @ 300mm c/c at its top and spanning in two directions having dimension 4.5m x 6m. In both direction tension reinforcement is 10mm 140 mm c/c. Soln (equation 3), can therefore greatly underestimate slab deflections. Rangan recognised this inadequacy and proposed an upper limit on the cracked stiffness of beams with low reinforcement ratios (equation 2) . The accuracy of this expedient will be examined in Section 3.3. ALLOWABLE SPAN TO DEPTH RATIOS FOR SLABS 3 . I Introductio

Hello Im curios to know the deflection values in my slabs so i can make a decision on whether to increase some slab depths or not, also there's this formula I do see in software for deflections , an example reads Deflection Check: L/d = 10.08 < 52.0 *** Su.. CIVL 4135 Deflection CHAPTER 13. DEFLECTION 13.1. Reading Assignment Text: Sect 6.4 through 6.7 and 6.9 ACI 318: Chap 9. 13.2. Calculation of Deflection of R/C beams Review of theory of deflection of homogeneous beams in elastic flexure: x y y(x) dx w(x) It is possible to make the following observations from geometry Deflection = y(x) Slope = dy/d

Permissible Deflection in Slab CIVIL SITE VISI

Please type the text you see in the image into the text box and submi Transcribed image text: Wu Example 1. Design for maximum bending &sh 2. Check for allowable deflection. Given IN 10m Wpl=conc. Slab (+hand rai par apet+ توزيع بالتساوي علي العتبات Longitudinal

Deflection check (beam and slab: EC2) Deflection check (beam and slab: EC2) The deflection of reinforced concrete beams is not directly calculated and the serviceability of the beam is measured by comparing the calculated limiting span/effective depth ratio L/d to the maximum allowable values as given by; 1. IF ρ ≤ ρ 0 Slab thickness and deflection. 1. Minimum thickness for solid one-way slabs unless deflections are calculated for slab not supporting or attached to partitions or other construction likely to be deamaged by large deflection. (ACI 318-05 Table 9.5a When a new check is added to the Slab Deflection Check Catalogue it initially defaults to the deflection limit set here. Allows you to define an amplification base factor for shrinkage. The value must be within the range from 0.1 to 0.9. Allows you to select between 2 creep/aging methods: User defined and Automatic Deflection must be calculated for thinner members One-way slabs 13 28 31 35 One-way beams and ribbed slabs 10 19 22 26 ACI 3 18-92(4') One-way slabs 13 25 29 35 One-way beams and ribbed slabs 9 19 22 24 NS 3473 E(42) Deflections must be calculated for thinner members Beams 8 16 18 21 One-way slabs 10 21 24 28 Two-way slabs . 10/07/2013

Q&A: Correcting Sagging Joists | JLC Online | Framing

Maximum Allowable Deflection In Steel Beam Eurocode - New

Slab deflection example (Eurocode) In the following exercise slab deflections will be checked for the tutorial model shown below. It is a simple multi-bay flat slab structure on an 8m square grid of columns I sized said beam by first modelling a linear support on the slab edge (which I would consider to be conservative due to the infinite stiffness of the support) and determining the appropriate second moment of area to yield a deflection of ~15mm (The approximate allowable deflection at the support which would yield a maximum deflection in the.

What is the 'limiting deflection' of a slab? - Quor

  1. 435, Deflection of Concrete Building Structures. His research interests are early-age member behavior, shrinkage, creep, deflection serviceability, and formwork pressures. Table 2—Minimum thickness of non-prestressed beams and one-way slabs unless deflections are computed (ACI 318-08 and CSA A23.3-04) Simply supported One end continuous Both end
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  3. In engineering, deflection is the degree to which a structural element is displaced under a load (due to its deformation).It may refer to an angle or a distance. The deflection distance of a member under a load can be calculated by integrating the function that mathematically describes the slope of the deflected shape of the member under that load
  4. ed for each slab item as the worst status from all associated check lines detected within the slab item or touching the slab item boundary. In the above status view: No check lines cross the slab items between C-D / 2-3 and C-E / 3-4 so the slab reports Unknown as no.
  5. Beams are the long members of a structure that carry the loads brought by the horizontal slabs of the structures, including floors and roofs. When beams carry loads that are too heavy for them, they start to bend. We call the amount of beam bending beam deflection. Beam deflection is the vertical displacement of a point along the centroid of a.
  6. In order to calculate the service limit state, SAFI GSE automated the slab spans detection. For each load combination and span, the Serviceability Limit State (SLS) ratio is calculated using the long-term deflections and the span length and compared to the relative deflection limits (L/x) defined by the user
  7. Another consideration as well, is post-tensioned and pre-stressed concrete are often engineered with only L/240 deflection criterion. This means a slab 30 ft long, supported only at the ends, (L/ 360 = 360/360) could have deflection up to 1 (25 mm). See TTMAC Detail 309F-98 for recommendations on installation over pre-cast concrete systems

1616.3.1 Allowable Deflections. 2020 FBC - Building, 7 th edition > 16 Structural Design > 1616 High-Velocity Hurricane Zones— General, Deflection, Volume Changes And > 1616.3 Deflection > 1616.3.1 Allowable Deflections. JUMP TO FULL CODE CHAPTER 1- Increase the Dimensions of the Element. This includes increasing the thickness of slabs and increasing the width and/or depth of beams. The benefit from increasing dimensions can be revealed if we mentioned the deflection equation of a simply supported un-cracked beam or slab. where I in the previous equation is the inertia Repairs of beams and Slab with excessive Deflection B. V. Bhedasgaonkar and M. K. Wadekar Excessive deflections of slabs and beams were observed in an office building of a sugar factory in western Maharashtra. The problems was analysed and it was found that the beams and slabs were underdesigned المرفقات. Deflection In Concrete Slabs And Beams As Per ACI Code And Other.pdf. 3.1 MB · المشاهدات: 107. مواضيع مماثلة. Deflections of reinforced concrete flat slabs by Estee M.rar. Control of Deflection in Concrete Structures. Deflection in concrete slabs & beams. Deflections in Concrete Slabs and Beams. calculation of deflection of rc beam / slab as per is 456-2000 { annex 'c' }. ( actual program is available in super civil cd) member designation: span of member [ m ] width of web [ mm ] depth [ mm ] clear cover to reinforcemen

that the SFRC slab has 16.6 % less depth than the plain concrete slab). Deflection Characteristics Figure 7-8 shows the fIrst crack deflection under load point for interior edge and comers of the SFRC and plain concrete slabs. The SFRC interior and comers at 15 design of floor slabs. The allowable soil bearing pressure is the maximum pressure that can be permitted on research shows that elastic deflections and stresses of the slab are predicted reasonably well when the k value is used to represent the sub-grade response. This same research indicates that the control of slab stresse

The CEB-FIP Code (990) was another model developed for the purpose of calculating deflection caused on composite slabs because of the forces of deflection that acted on composite slabs. According to the model, the applied moment and the rigidity of the composite concrete slabs are used to calculate the curvature of the material under. allowable deflection to 50 and 150 psf design live loads. slab ultimate load load at allow. test load / 50 test load / 150 # capacity deflection *) ultimate load load at allow. ultimate load load at allow. (psf) (psf) capacity deflection capacity deflection 1 730 345 14.60 6.91 4.87 2.30 2 700 326 14.00 6.52 4.67 2.17 3 600 238 12.00 4.76 4.00 1.5 Theoretical deflections of the square reinforced concrete slabs can be approached by several different methods# Solutions of differential equations of curvature together with the boundary con ditions is a very long and tedious task* The problem may be interpreted as seeding the functions which satisfy the boundar In general the deflection limits are based on beam members lengths (span) which results in different allowable deflections in every point or node of the construction. For example the serviceability limits suggested by the UK National Annex for the Eurocode 3 (BS EN 1993-1-1) for allowable vertical and horizontal deflections are shown below

Deflection of Slabs - Civil Engineering Knowledge Bas

These reports include AC1 435.2R, Deflection of Reinforced Concrete Flexural Members, AC1 435.1R, Deflection of Prestressed Concrete Members, AC1 435.3R, Allowable Deflections, AC1 435.6R, Deflection of Two-way Reinforced Concrete Floor Systems, and AC1 435.5R, Deflection of Continuous Concrete Beams. Chapter 1 - Introduction Chapter 2. C = allowable timber stress, psi, in compression || to grain ∆ = deflection, in. ∆max = maximum deflection, in. E = modulus of elasticity, psi f = allowable stress in extreme fiber in bending, psi h = depth of beam cross section, in. I = moment of inertia, in.4 ( I =bd3 12 for rectangular beam) Ib Q = rolling shear constant L = span, ft In this section, two types will be discussed, one-way solid slabs and one-way ribbed slabs. 8.2.1 One-way Solid Slabs Minimum Thickness To control deflection, ACI Code specifies minimum thickness values for one-way solid slabs, shown in Table 8.1. These values are applicable for normal loading condition However, it has been recognised that deflection in a concrete beam and slab increases with time for up to nine years. The long-term deflection of a reinforced concrete member under sustained load is mainly due to creep and shrinkage, and it is usually larger than the immediate deflection [2] Two methods for calculating deflection are presented below, and these are based on the advice in TR58 Deflections in concrete slabs and beams8. Rigorous method. The rigorous method for calculating deflections is the most appropriate method for determining a realistic estimate of deflection. However, it is only suitable for use with computer software. The Concrete Centre has produced a number.

Beam Deflection Limits Uk - New Images Beam

What Is Acceptable Deflection In A Beam - New Images Bea

Slab surface geometry is a function of the as-constructed surface geometry and the load-induced post-construction distortion of the slab deflection surface5 including both the initial settlement of the foundation and distortion due to expansive soil movement. When using slab surface elevation measurements to evaluate the performance of a slab-on Flat slab design can be stressful budget breakers. Tekla Structural Designer's new rigorous slab deflection capabilities efficiently addresses these challenges. It maintains an easy to use interface and inputs and comprehensive output shedding light on the black box of traditional slab design

8. Check for Deflection: Allowable L/d = 35 X M.F.X 0.8. M.F is Obtained from IS:456-200 P-38 Fig 4; Find actual, L/d. If Actual L/d < allowable L/d ———- Ok. 9. Check for Development Length: IS 456-2000,P.44, Cl. C. Ld should be ≤ 1.3 (M1/V) + L0. Wher Vertical shear, horizontal shear and deflection will be investigated in order to motivate the safe use of German research factors in combination with SANS 10100:2000. The economy of Cobiax slabs will also be investigated to establish graphs comparing Cobiax slabs, coffer slabs and post-tensioned slabs for different spans and load intensities

Simply Supported Beam Deflection Example

Deflection of slab-on-grade - Structural engineering

An allowable design deflection of L/360 for concrete members is only satisfactory when longterm deflections resulting from creep, shrinkage and temperature effects have been included. The fact that the design live load is seldom attained in service is of little significance in this case 18. SUMMARY• A beam-and-slab system, with a one-way slab, and beams cast compositely with the slab, is a highly efficient floor system.•. The slab is designed as a continuous slab, using theory of continuous beams (slabs), or the simplified 'coefficient' method (where applicable i.e. most of the time).•. Edge beams act as L-beams, and. Long Term-Deflection in slabs/beams is the deflection or the deformation that occurs over time due to shrinkage and temperature. It is also influenced by the condition of the cracking before loading, then creeping, which depends on the time passed to the time of the first loading, the environment, and other factors

Causes of Excessive Deflections in Reinforced Concrete Slab

Floors - Fiber Allowable Defl. Calculate the allowable deflection for a fiber reinforced concrete slab-on-grade floor. Design Problem 1. Calculate the required thickness of a concrete slab-on-grade for a warehouse floor The floor slab design procedure presented The maximum allowable stationary live load is lim- herein is based on limiting the critical tensile stresses ited by both the positive bending moment stress produced within the slab by the vehicle loading, as under the load and the negative bending momen The effect of construction loading on deflection multipliers C is shown in Fig. 7 for (a) the slab in Fig. 1 and (b) a slab similar to that in Fig. 1 with the simple support replaced by a wall with rotational stiffness, per 7 5 m width, equal to a 400 X 250 column with its minor axis oriented parallel to the slab edge

Design beam for deflection - YouTubeVibrations of Cantilever Beams:PLS4 - Bypass Slab Slide Strut - SCAFCO Steel Stud Company

For example, the maximum deflection for a joist span of 15′ is [15 * 12] / 360 = 1/2″. The L/360 formula is useful for most ceramic, porcelain, and hard stone. For soft-stone tile, such as limestone or light marble, the L/720 formula applies (cutting the maximum allowable deflection in half) one-way slabs, joists and beams, the actual immediate and long-term deflections must be calculated per the requirements of Section (using Ie). In addition, the actual deflections calculated must comply with the permissible deflections allowed by Table 9.5(b). It should also be noted that when calculating th This Method Statement details general procedure for slab deflection testing on any kind of project or building. Project Manager has the overall responsibility for the implementation of this method statement and shall well ensure that the Independent Testing Agency and as well as other team members are aware of the requirements of the Method Statement term slab deflections. Since precast cladding is normally manufactured to fixed dimensions, it is generally the deflection of the slab relative to the supports around the perimeter, both before and after installation, that is of particular interest. In contrast, with internal partitions, it is generally the deflections subsequent t Curvature in a simply supported slab. This 'rigorous' method is described in greater detail elsewhere e.g. The Concrete Society publication: TR58: Deflections in concrete slabs and beams, 2005, or How to design concrete structures using Eurocode 2: Deflection Calculations.It is backed by site-based research