However, this is not the only means of reinforcing slabs. The scope of this article is limited to the design of industrial concrete floor slabs on grade for concentrated loads caused by the columns of freestanding. The most common reinforcement associated with slabsongrade is welded wire fabric. This section covers below grade construction details that apply to all building types, for either combustible or noncombustible construction classifications. Empirical method a method of design and analysis based on a nationally approved or equivalent standard may be used to design slabson.
Slab on grade or grade slab types construction procedure. Packard portland cement association, 1976 concrete floor slabs on grade subjected to heavy loads army technical manual tm 580912, air force manual afm 883, chapter 15 1987. Aci 360, design of slabson grade, refers to this as a type b slab. The effects of stationary live, dead, and wall loads and moving live loads. Slabongrade and grade beam design concrete engineering. Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems. It assumes that the area under the slab as well as the slab edge are insulated to a minimum of r 10 rsi 1.
Download free demo updated august 8, 2019 soilstructure slab on grade software simplifies the calculation of a. Asce, secb course content slab on grades construction. The slab on ground is in direct contact with the typical draining layer such as. Stresses in floor slabs on grade resulting from vehicular loads are a function of. Reinforced concrete slab design and detailing guide is456. Stresses in floor slabs on grade resulting from vehicular loads a re a function. Determine the loads based on the buildings parameters section d. A new method for designing floor slabs on grade due to the difficulty of applying simplified design methods, amongst them being the portland cement association pca and wire reinforcement. Aci 360, design of slabs on grade, refers to this as a type b slab. Development of the design approach the primary design issues for stiffened slabs on grade are the sizing of the beams that stiffened the slab and the. Empirical method a method of design and analysis based on a nationally approved or equivalent standard may be used to design slabson grade as foundations.
Pdf this article presents a methodology for designing slabs on grade for industrial floors where there is an eccentricity between the slab centroid. The design procedure specifies the thickness and width of the horizontal wing of insulation that is to be installed around the perimeter of the slabongrade. It includes general information to consider when working with nudura in both plan and vertical section layout including. Introduction concrete slabs on grade are a very common type of concrete construction. The materials to be used are grade c25 concrete and grade. The report addresses the planning, design, and detailing of slabs. Nov 12, 2018 before casting slab on grade, the earth is excavated up to the required depth and compacted to expel air voids. Chapter 18 concrete slab structures january 2019 188 18. Grdslab concrete slab on grade analysis spreadsheet. For slabs with light loads, as those for homes, include wire mesh midway up the thickness of the slab to reduce cracking. The slab thickness depends on the type of loads on the floor slab. For example, in a 4inch 100 mm thick slab the joint spacing should be about saw cut tooled wall or column expansion joint material slab on grade column contraction joints intersect at diagonals of the square form openings which will be filled after floor has hardened concrete cracks below joints slab isolated from. This section covers belowgrade construction details that apply to all building types, for either combustible or noncombustible construction classifications. After this publication, it was subsequently adopted by the uniform building.
Only the design of slab bridge will be used for illustration. Manual for design and detailing of reinforced concrete to the september 20 code of practice for structural use of concrete 20 2. A4 slab design using posttensioning a5shrinkagecompensatingconcreteexamples chapter lintroduction l. Tm 580912 concrete floor slabs on grade subjected to. Design the minimum slab thickness to support a fork lift specified below and storage racks specified below throughout. The slab is outside buildings which subjected to 1 hr fire resistance and design. Ce 437537, fall 2002 slabongrade example design info 1 8 design the thickness for a slabongrade concrete slab in a warehouse. In most cases, the slab thickness is designed as an unreinforced concrete section. Find the following parameters for design moments in step 2 per unit width step 4 note. The construction and design of concrete slabs on grade d. Design of slab for flexure 067 m unit width of slab.
Pdf a new method for designing floor slabs on grade due to the. This grade slab acts as the foundation for a home or building, and provides a stable base for w. Example on design of slab bridge design data and specifications superstructure consists of 10m slab, 36m box girder and 10m tgirder all simply supported. Reinforced concrete design 1 design of slab examples and. Department of transportation bridge deck design using grade 60 steel astm a615, f y 60 ksi and epoxycoated reinforcing steel was compared to deck slab specimens where grade 60 is replaced with crr bars. Some foundations used for light buildings on shrinkswell soils. Stiffened slab on grade elevated structural slab on piers stiffened slab on grade and on piers thin post tensioned slab figure 1.
This strip is designed basically as if it were a 12inchwide beam, t inches thick. Oneway simply supported slab analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. Slab on grade design guidance structural engineering. Determine slab thickness and concrete strength as if the slab were unreinforced. Pdf a new method for designing floor slabs on grade due to. Design a thickened slab to support the columns and. The design procedure includes determining slab thickness based on moving live loads and then checking adequacy of slab thickness for.
Reinforced concrete sk 33 section through slab showing stress due to moment. Concrete floor slabs on grade are subjected to a variety of loads and loading conditions. Aci 360, design of slabsongrade, refers to this as a type b slab. Determining the purpose of the slab sound design of a slab on grade begins with determining the intended use and performance criteria. The slab has to carry a distributed permanent action of 1. Design of slabs onground reported by aci committee 360 aci 360r06 this document presents information on the design of slabs onground, primarily industrial floors. What is grade slab and what is the difference between grade. Reinforced concrete design 1 design of slab examples. Manual for design and detailing of reinforced concrete to the. Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for oneway and twoway slabs as per is 456. Install a polyethylene slipsheet directly beneath the slabs. And then, soil investigation is done to design the thickness of the slab. The pti design procedure is used to design a slabon grade foundation that will respond.
Dhang, department of civil engineering, iit kharagpur. Tm 580912 concrete floor slabs on grade subjected to heavy. Floor slabs can range from a simple residential basement slab to a heavyduty industrial floor. Concrete slab on grade analysis calculator for post or wheel. The major structural components of a slabongrade foundation are the floor slab itself and either grade beams or foundation walls with footings at the perimeter of the slab see figures 42 and 43. For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3. Soil design parameters edge moisture variation distance. Divide the floor into slabs no more than 110 ft by 110 ft. Ce 403, fall 20 oneway slab design 2 4 aci 31811 referenced pp 2 4 typical concrete floor systems copied from ceco concrete construction pamphlet design procedure a oneway slab is designed by considering a onefootwide strip of slab. Powered by a sophisticated fem solver increasing capacity and substantially speeding up solution for large and complex models, spmats v8. Design and construction of concrete slabs on grade, aci scm1186, american concrete institute, detroit, 1986. This manual p rescribes the criteria for the design of concrete floor slabs on grade in buildings for heavy loads and is applicable to all elements responsible for military construction. Structural design guidelines for concrete bridge decks.
Make the slabs square or rectangular, with an aspect ratio not to exceed 1. Design of slabsonground aci 360r06 by american concrete institute slab thickness design for industrial concrete floors on grade is195. These boards act as a concrete mould, which helps in identifying slab corners. Both methods use the same procedure to divide the moments so found between the middle strip and column strips of the slab and the beams if any. Background information on design theories is followed.
Batters are marked and placed in position as per plan before concrete pour. Department of transportation bridge deck design using grade 60 steel astm a615, f y 60 ksi and epoxycoated reinforcing steel was compared to deck slab. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1. Jul 02, 2010 lecture series on design of reinforced concrete structures by prof. Ground supported slabs are frequently designed with a single. Slabongrade and grade beam design gourile civilenvironmental 17 dec 01 00. The thermal resistance and width of the perimeter insulation is specified. The construction and design of concrete slabs on grade. Ce 437537, fall 2002 slabongrade example design info 1 8. Use of 500 grade steel in the design of reinforced concrete slab prof. Before casting slab on grade, the earth is excavated up to the required depth and compacted to expel air voids. With some limitations, reinforcement for slabs can be sized using the subgrade drag theory in order to increase the spacing of control or construction joints. Lecture series on design of reinforced concrete structures by prof. Reinforcing is added to control shrinkage cracking and maximize the distance between designed joints.
Simply supported one way slab a rectangular reinforced concrete slab is simplysupported on two masonry walls 250 mm thick and 3. Although many concrete slabs can satisfactorily be cast directly on a soil subgrade, some slabongrade sys tems can be significantly improved by the addition of. A3 design examples using coe charts a4 slab design using posttensioning a5shrinkagecompensatingconcreteexamples chapter lintroduction l. In this context, design is defined as the decisionmaking process of planning, sizing. The designer determines the required slab thickness after determining the controlling loads, the appropriate safety fact o r, and the subgrade modulus. Slabs on grade identifying the problem slabonground is a wellused building solution in north america and other parts of the world, and they are very well known to not provide healthy interior environments. Slab on grade design guidance once20036 structural 26 may 17 12. The result is a lightly reinforced slab designed to offset the effects of temperature and shrinkage of the concrete. The design procedure includes determining slab thickness based. A3design examples using coe charts a4slab design using posttensioning a5shrinkagecompensatingconcreteexamples chapter lintroduction l. Floor slab design floors are designed as slabs on grade. General design process though many details must be included in the design of a slab on grade, three important components are slab thickness, reinforcement requirements, and joint spacing.
Basic design criteria concentrically loaded d2 all sides c critical section for twoway shear b critical section for oneway shear a critical section for flexure outside face of concrete column or line midway between face of steel column and edge of steel base plate typical extent of footing typical d foundation design 8. The design procedure set forth in that publication had at that time been in use by the author for about 15 years. For 6 to 10 thick slabs on grade with k values between 100 pci and 200 pci, the increase in stress, i, due to a 2nd wheel or post load as a percentage of stress for a single wheel or post load is approximately. Concrete slab resting on grade containing steel reinforcement which consists of either a welded wire fabric or deformed reinforcing steel bars.
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