Guide to the design and construction of reinforced concrete flat slabs contents membersof the projectsteeringgroup list of tables vii iv list of figures v 1. If the slabs consist more than one panel or corner of the slab are prevent against lifting it is define as twoway restrained slab. Recommendations for finite element analysis for the design of. Design of reinforced concrete flat slabs to bs 8110 civil. The finite element method is commonly used to design the reinforcement in concrete slabs. Analyses are for a onebaywide strip using the equivalent frame analysis method of the aci code. Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems. The slab is 300 mm thick and columns are 400 mm square. The strip may have up to 20 spans and may have cantilevers at the ends. Design of reinforced concrete flat slabs to bs 8110.
Apr 19, 2016 economically design posttensioned and reinforced concrete floors including slabs, mats, and rafts, with exceptional visibility into compliance, efficiency, and practicality. Design the shear reinforcement shear studs at the edge and interior columns. Flat slab design spreadsheets to eurocode 2 en 19921. Sep 27, 2017 flat slabs design is appropriate for most floor situations and is also suitable for irregular column layouts, curved floor shapes, ramps etc. Design for bending edge panelsapportionment of moment exactly the same as internal columnsmax.
Punching of flat slabs design for shear at th e column heads 12. The concrete floor slab system shown below is for an intermediate floor to be designed considering partition weight. General a slab is a flat two dimensional planar structural element having thickness small compared to its other two dimensions. Jointed floors with steel fibers in these floors, closelyspaced sawcut joints form the main defense against random cracks. Sachpazis date 18012014 chkd by date appd by 3 pass span to depth ratio is ok internal bay bc effective span.
Design of reinforced concrete structures ii twoway slabs 8 c. Flat slabs may have drop panels at columns and columns may have capitals. Civilax is the knowledge base covering all disciplines in civil engineering. Rectangular panels with longtoshort span ratio 2420 1.
This design is a complete flat plate slab design, from shear to bending along with design of columns and shear head reinforcement. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. Flat slab design spreadsheets to eurocode excel sheets. Different types of shear reinforcement used at column heads. Guide to the design and construction of reinforced concrete. Equivalent frame method most commonly used method the flat slab structure is divided longitudinally and transversely into frames consisting of columns and strips of slabs with. Design of reinforced concrete structures ii twoway slabs. Flat slab analysis and design designs beamless concrete slab floors flat slab or waffle slab in accordance with aci 318. Pdf design of flat slab worked example mohamed hussein. How to design reinforced concrete flat slabs using finite.
The analysis and design follow the equivalent frame analysis method of the aci code, which considers a onebay wide strip of the floor system as a continuous frame. Analyze and design flat slab or waffle slab floors. Bending will take place in the two directions in a dishlike form. Aug 27, 2015 guide to the design and construction of reinforced concrete flat slabs contents membersof the projectsteeringgroup list of tables vii iv list of figures v 1. Design considerations for reinforced concrete flat slab floor. Flat slab analysis and design free version download for pc. Ufc 332006a concrete floor slabs on grade subjected. All internal floor slabs on ground shall be on moisture barrier equivalent to detailed 300 micron a. Design of reinforced concrete structures ii twoway slabs 1 1.
We aim to close the gap to the industry by improving the awareness about. A finite element model may be created to analyse a complicated loading arrangement. Analysis and design of flat slab by aci code with matlab coding. Due to simplicity of design and construction, the concrete slab structure is relatively economical. The slab is for an offi ce where the specifi ed load is 1. The benefits of choosing flat slabs include a minimum depth solution, speed of construction, flexibility in the plan layout both in terms of the shape and column layout, a flat soffit clean finishes and freedom of layout of services and scope and. Structural modeling and analysis of concrete floor slabs. Where the slabs are ribbed in two directions, they may be designed as twoway spanning in accordance with 3. Accordingly, main reinforcement is required in the two directions. The design i am going to share with you today is design of flat plate slab as by definition. This pdf file contains a chapter of 23 pages with various aspects of flat slabs including four example of flat slab design. Most designs space the joints no more than 20 ft apart.
Guide to the design and construction of reinforced. Heavy loads in building s such as warehouses include moving load s, stationary live loads, and wall loads. Comparative study of reinforced concrete flat slabs with and. In order to simplify the analysis and to be able to use the superposition principle for evaluating the effect of load combinations, linear analysis is generally adopted even though concrete slabs normally have a pronounced nonlinear response. Department of mechanics, materials and structures english. Design for flexure check if the direct design method of aci sect. The lateral loads are independently resisted by shear walls. Flat slabs design is appropriate for most floor situations and is also suitable for irregular column layouts, curved floor shapes, ramps etc. Oneway and twoway slabs university of asia pacific.
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. Recommendations for finite element analysis for the design. Total moments in rectangular panels with square capitals 440 moments at design sections of rectangular slabs with 146 147 square column capitals 0 0 0 0 0 0 0 0 0 0 0 148 45. The design bending moment of twoway restrained slab can be calculated as follows. Flat plate slab is that in which slab is directly supported on columns without column capital, drop panel or beams. Twoway flat slab concrete floor with drop panels system analysis and design design the concrete floor slab system shown below for an intermediate floor considering partition weight 20 psf, and unfactored live load 60 psf. Figure 6 gives a modification coefficient which will adjust the cantilever length for smaller slabs depending on the slab size. Its limitation lies in the practical range of span lengths and. Slab construction and expansion joints shall be incorporated in the design, and shall be positioned to minimise movement and cracking in slabs, and to avoid unsightly gaps in floors and walls resulting from any movement of the structure.
Aci code has specified the fixed coefficients for lateral and transverse distribution of moments as per direct design method and equivalent frame method. Aci 11790 states that the levelness tolerance fl shall not apply to slabs placed on a supporting structure that is unshored, cambered, or inclined. Design the prestressing for all three spans for service stress conditions. For lower loads they can have constant thickness and are called flat slabs or flat plates, see figure 1. Concrete slabs are commonly divided into the following types. This article discusses the similarities and differences between traditional frame methods and finite element methods for the design of floor slab systems. We aim to close the gap to the industry by improving the awareness about latest trends in civil engineering. Analysis and design of flat slab by aci code with matlab. Firstly, one has to check if the design shear force v d is smaller than the maximum punching strength v rd,max.
For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3. Design of post tensioned flat slab structures in ram concept. This condition occur when the slabs are connected monolithically with support. Common practice of design and construction is to support the slabs by beams and support the beams by columns. Flat plate concrete floor system does not use beams between columns or. Cross sectional constant defines torsional properties c x.
It provides a working flat surface or a covering shelter in buildings. Twoway flat slab concrete floor with drop panels system. They may be supported on two opposite sides only fig. Oneway simply supported slab analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. The concrete centre, part of the mpa mineral products association mpa is the trade association for aggregates, asphalt, cement, concrete, dimension stone, lime, mortar and silica sand industries. Heavy loads in building s such as warehouses include moving load s.
Flat slab analysis, design and detailing pdf civil. Twoway flat plate concrete floor system design structurepoint. Reinforced concrete slabs compatibility limit design research. For slabs spanning in both directions published tables and charts should be used to find bending moment and shear per unit width of slab. Nov 29, 2012 civilax is the knowledge base covering all disciplines in civil engineering.
Beamless slabs beamless slabs are supported only on columns and are applied mostly in large industrial and public buildings. Design floors and foundations reliably and efficiently, saving time and money, and overcoming the most common concerns you face as a designer. The unified facilities criteria ufc system is prescribed by milstd 3007 and provides planning, design, construction. Our aim is to enable all those involved in the design, use and performance of concrete and masonry to realise the potential of these materials.
Twoway flat plate concrete floor system analysis and design the concrete floor slab system shown below is for an intermediate floor to be designed considering partition weight 20 psf, and unfactored live load 40 psf. Aci 360, guide to design of slabsonground describes these floors as slabs. The final deflected shape of the slab influences the floor levelness and is not solely a function of the concrete floor placement. Moments at design sections of slabs with square column capitals 0 0 0 0 0 43. In this study fe analysis of flat slabs is proposed.
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