Ground bearing slab strength of materials concrete. Feb 05, 2017 in my opinion,you need not to calculate the bearing capacity of the slab,the only thing we need to calculate is the bearing capacity of soil. Download data sheets search products by application download typical details find your local stockist take one of our online cpds. Design of slabsonground regarding shrinkage cracking chalmers. As such, this note aims to motivate the design and development of steel fibre reinforced ground bearing slabs, based on the most uptodate information available at the.
But even when plans and specifications for slabs on. Knowing the load bearing capacity of your concrete is essential to make sure that what you plan to have supported by the wall or slab will not be too heavy and cause it to crack and break. It brought together guidance for all types of industrial ground slab in one publication and also introduced a new design method for fabricreinforced groundbearing. Ground bearing concrete floors, industrial concrete hardstandings and concrete highway pavements have not, in the past, been perceived as a single type of structural element and their construction has taken place independently of each other. In residential and commercial buildings, a very thick concrete slab is supported on foundations andor on the subsoil which is used to build the ground flooring of a building. A concrete slab is a common structural element of modern buildings, consisting of a flat. The column is on the ground floor of a three storey building and the length is 4. This is in spite of their obvious commonality in the areas of design, materials, geotechnical appreciation and construction. The construction and design of concrete slabs on grade.
Precast slabs precast balconies lifting and transportation castinsitu structures foundations slabs walls columns ground bearing concrete floors free movement joints screed rails load transfer systems deltabeam slim floor structure bolted column connections. Asce, secb course content slab on grades construction. Advantages and disadvantages of concrete slab floors hunker. Use the appropriate drawing for the condensing unit being installed.
These slabs are generally classified as ground bearing or suspended. Ca post loads and concentrated loads concrete bearing and shear stresses for cupolex slabs are computed using design methods to see whether the stresses are within allowable. The depth of a concrete slab floor is very small compared to its span. Riwtd152 typical detail at top of internal masonry wall with ground bearing slab. A slab is groundbearing if it rests directly on the foundation, otherwise the slab is. Fabricreinforced concrete ground slabs and concrete society. Calculators for structural engineers, construction professionals and steel building specifiers. What is slab, beam, column, and footing construction.
Uniformity of the subgrade and adequacy of its bearing capacity. Reinforcement for slabs on ground concrete construction. An introduction to ground bearing floor slabs, touching on the slabs reinforcement by considering both historical use of mesh as well as current plastic and steel fibre reinfocement methods. Ground bearing slab strength of materials concrete scribd. Yes no continues on reverse ground bearing floor slabs general is the proposed slab a minimum of 100mm thick yes no note. Slab on ground design should result in sufficient strength to support without distressing the loads applied to the finished surface. Rupture depth of an unreinforced concrete slab on grade pdf. Using hetenyis equations for a slab subjected to a uniformly distributed load over part of its area. How to determine the soil bearing capacity of reinforced. Concrete is often used to fill the base of a house, create the basement and to make a solid foundation. Unreinforced ground supported slabs should be in accordance with bs en 2061. They were once common in the usa, but the economic value of reinforced ground bearing slabs has become more appealing for many engineers.
The overall tendency is to shrink and this can cause cracking at an early age. Cracks in slabs on ground american society of concrete. Nevertheless, they can also be installed in all types of structures where there is no basement, provided that ground conditions are suitable. Concrete slabonground floorfootings also provide a. When a concrete slab forms part of the roof construction of a building, it is normally referred to as the roof slab. One of the most common applications for unreinforced slabs is in concrete roads. Sybie, get a copy of concrete ground floors their design, construction and finish by deacon. A comparison with conventional design methods is performed. Abstract consideration is given to the analysis and design of ground bearing warehouse slabs, in particular the analysis of the slab of a new warehouse whose performance has been monitored. Grdslab concrete slab on grade analysis spreadsheet. It is usually timber but steel is commonly used on commercial projects. In 2003, the third edition of concrete society technical report 34 1 was published. Ground bearing concrete slabs chapter 2 wall concrete.
In one practical, yet comprehensive volume, it integrates the three crucial phases in the development of ground bearing concrete slabs design, specification and. This technical guidance note describes how steel fibre reinforced concrete ground bearing slabs are designed. Concrete slab on grade analysis calculator for post or. Unreinforced or plain slabs are becoming rare and have limited practical applications, with one exception being the mud slab see below. Riwtd154 top of internal concrete retaining wall with ground bearing slab.
There are numerous applications of synthetic fibres. Installation instructions for ground concrete slab mount. Fabricreinforced concrete ground slabs and concrete society technical report 343. The ground workers handbook gives guidance to site managers and site staff on any particular issues on your site for traditional forms of construction. It brought together guidance for all types of industrial ground slab in one publication and also introduced a new design method for fabricreinforced ground bearing slabs. Ground bearing concrete floors, industrial concrete hardstandings and concrete highway pavements have not, in the past.
Flat slab analysis, design and detailing pdf civil. This video shows you how to calculate the amount of concrete required to pour a concrete slab on ground with splayed edge beam and a rebated. How to calculate the load bearing of concrete hunker. Ground bearing concrete slabs chapter 2 free download as pdf file. However if you dont pour concrete then, concrete slabs are another alternative for basement floors and walls. Reported by committee 302 american concrete institute. A civil engineer must know all the aspects regarding the flat floor system. Step 16 assess punching shear and bearing stress under post loads sections 3. Slabs on ground typically are designed as unreinforced sections. In contrast, micro synthetic fibres,with diameters between 18 and 34 microns. Flat slab system is an important division of concrete floor system. Fabricreinforced concrete ground slabs and concrete society technical report tr343alasdair n beal, thomasons.
Pdf fabricreinforced concrete ground slabs and concrete. Without reinforcement, the entire load on these slabs is supported by the strength of the concrete. Concrete slabs that form the ground floor of a building may be either supported on beams called a suspended slab or supported directly on the subsoil, via hardcore, for example called a ground bearing slab. For enough reinforcing to accomplish enhanced aggregate interlock, the american concrete institute aci committee 360, design of slabs on ground noted that designs using 0. Grdslab is a spreadsheet program written in msexcel for the purpose of analysis of concrete slabs on grade. Technical thestructuralengineer 35 technical guidance note. Online concrete slab on grade analysis calculator for slab subjected to interior concentrated post or wheel loading assuming slab is reinforced for shrinkage and temperature only. Concrete bearing and shear stresses for cupolex slabs are computed using design methods to see whether the stresses are within allowable cupolex concrete slabs may be great enough that alternative designs should be. Because the concrete slab on ground is assumed to be continually supported, an adequate soilsupport system is critical to the slabs performance. Foundations 3 fire resistance of column using equation 5. Slab on ground is a wellused building solution in north america and. Cip 6 joints in concrete slabs on grade what are joints. Specifically, a concrete slab on grade may be subjected to concentrated post or wheel loading. The formwork defines the shape of the final slab when the concrete is cured set.
Our design was for a 150 thk ground bearing slab sitting on 1. The construction and design of concrete slabs on grade 2012 instructor. The influences of the soil load bearing capacity, as well as the loss contact between soil and slab. This comprehensive new reference work provides invaluable information to designers and specifiers throughout the design and construction project and beyond.
Ground bearing concrete slabs has been specifically written to break down the walls that have arisen between these three areas and focus on the issues that are common to them all. Macro synthetic fibres are typically 30 to 65 mm long and are used for structural performance. Where floors are finished with sandcement screeds insulation can be positioned above or below the slab. Does the ground bearing floor slab align with the project summary sheet and foundation design. Introduction concrete slabs on grade are a very common type of concrete construction. Slabs transmit the applied floor or roof loads to their supports. Mud slabs, also known as rat slabs, are thinner than the more common suspended or ground bearing slabs usually 50 to 150 mm, and usually contain no reinforcement. Concrete society report tr34 concrete industrial ground floors third edition 2003 important errata notification would you please amend your copy of tr34 to correct the following. They often argue that faulty design, materials, or construction must have caused such cracks. The trench excavations located beneath slabs should be backfilled with hardcore and consolidated without damaging the brickwork below dpc level. Pdf structural glass fiber reinforced concrete for slabs. The method of proof rolling well help us to know whether the full layer of soil is able to behave as a supporting system i. In many domestic and industrial buildings, a thick concrete slab supported on foundations or directly on the subsoil, is used to construct the ground floor. A slab is ground bearing if it rests directly on the foundation, otherwise the slab is suspended.
For most situations where internal floor areas are greater than 600mm below external ground level, additional protection may be required. Beams, see lecture 3 punching shear requirements e. Ground bearing floor slabs are most commonly found within industrial installations, such as warehouses or factories. The construction and design of concrete slabs on grade d. Commonly, slabs are supported by beams, columns concrete or steel, walls, or the ground. F or many years, the uk bible for designing concrete ground bearing slabs was colin deacons concrete ground floors. Floor slabs can range from a simple residential basement slab to a heavyduty industrial floor. Ground bearing concrete slabs ground bearing concrete floors, industrial concrete hardstandings and concrete highway pavements have not, in the past, been perceived as a single type of structural element and their construction has taken place independently of each other. Elements of a typical concrete industrial floorpavement.
Ground bearing concrete floor slabs should be protected against ground moisture by providing a continuous membrane, details of which are given in the materials section. Thickened slab areas and the floor slab can be poured in one operation. The design and construction of concrete floors on ground does not need to be a complicated procedure. Table 5 shows that ground bearing slabs can be poured up to 81m in length between free movement joints depending on the thickness of the slab and the mesh used. Tm 580912 concrete floor slabs on grade subjected to. For these types of construction, a structural engineer should be consulted. Care should be taken not to trap moisture when a combination of damp proofing and vapour control layers are used.
On one hand there are what may be termed conventional slabs with steel reinforcement mesh. Harvey, lecturer department of civil engineering, queen mary college, london, u. Irregular cracks are unsightly and difficult to maintain but generally do not affect the integrity of concrete. There are both advantages and disadvantages of using these slabs in your home, though.
Structural glass fiber reinforced concrete for slabs on ground. Ground bearing concrete floor slab 31 suspended floor constructions 32 horizontal damp proof courses 34. Movement joints in ground bearing slabs and rc retaining. Ground bearing concrete floor slabs should be at least 100mm thick. A ground bearing slab is a resting slab directly on the foundation. Nov 28, 2007 for enough reinforcing to accomplish enhanced aggregate interlock, the american concrete institute aci committee 360, design of slabs on ground noted that designs using 0. This is a relatively recent innovation that continues to evolve. Ground bearing concrete floors, industrial concrete hardstandings and concrete highway pavements have not, in the past, been perceived as a single type of. Pdf structural glass fiber reinforced concrete for slabs on. Fabricreinforced concrete ground slabs and concrete. While ground bearing slabs are essentially similar, their method of construction varies according to the likely end use and the accuracy of building required. Some insulation materials can even be positioned below the damp proof membrane. On the other there are fibre usually steel reinforced slabs designed to. This type of floating floor finish can be laid over ground bearing concrete slabs or precast suspended floors explained larter in this section.
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