flat slab types of flat slab design and its advantages flat slab is a reinforced concrete slab supported directly by concrete columns without the use of beams. flat slab is defined as one sided or two-sided support system with sheer load of the slab being concentrated on the supporting columns and a square slab called drop panels.
ribbed slabs are common types of slabs. the main advantages of using ribbed slabs are permitting a given minimum clear height to be maintained with a reduced overall story height, covering a big horizontal area, simple formwork and reduced own weight. the system exhibits higher stiffness and smaller defections.
one way ribbed rcc slab is a simply simply supported slab in most cases one-way ribbed slab design and detailing using autocad how to design 1 way rcc ribbed slab using etabs
advantages of hollow slab. reduced slab weight due to reduced amount of concrete below neutral axis. ease of construction, especially when all beams are hidden beams. economic for spans > 5m with moderate liveload: hospitals, office and residential buildings. attractive soffit appearance if exposed.
structural design 2 ribbed joist , hollow pot and waffle slab design to bs 8110 mr.asish seeboo 3 1.0.3 advantages and disadvantages of ribbed slabs advantages o longer spans with heavy loads 12-15m o reduction in dead loads due to voids o electrical and mechanical installations can be placed between voids
introduction hollow block and ribbed slabs are formed by placing blocks on the slab and concrete ribs. in case of hollow block slab voided blocks are placed to reduce the total weight of the slab . in case of ribbed slab the blocks are not permanent. the blocks are considered as non-structural element as they do not contribute to strength of the slab. blocks may be made concrete with lightweight aggregate or other material as polystyrene foam . types hollow block slab are one way and two
hollow blocks are used to fill portions of the slab thickness; this results in deeper arm for the reinforcement while saving the amount of concrete and hence the own weight of the slab. the reinforcement is located between the blocks inside the ribs. clay pot or blocks can be used.
when one says ribbed slab it is actually a one way spanning system with ribs where as in waffle slab the joists form a two way system. waffle slabs are usually deeper than ribbed slab but they have a thin topping slab with narrow ribs. however, column heads or band beams are of the same depth as the ribs.
disadvantages: depth of slab between the ribs may control the fire rating. requires special or proprietary formwork. greater floor-to-floor height. large vertical penetrations are more difficult to handle.
1.0.1 introduction to ribbed slab design to bs 8110. consider the solid slab shown below. in general, it is seen that in solid slab a portion of concrete below the neutral axis remains ineffective. this ineffective concrete does not contribute to the bending strength of the slab.
re: ribbed concrete slabs hollow block slabs design? thanks, do you have a video for this procedure, please? you mean that the top slab will be designed normally as a separate solid slab, and rips designed separately?
disadvantages of the post tension slab here are a few disadvantages of post tension slabs: 1. since there are a number of tendons and wires spread inside the post tension slab, it can result in corrosion. but largely, this tendency to corrode depends on the quality of the material used. 2.
ribbed slab design spreadsheets to eurocode ribbed slabs are widely used in many countries. this is attributed to the rapid shattering, ease of construction, and the reduction in the time of erection.
disadvantages of ribbed and waffle slabs not suitable where the live loads are huge as heavy manufacturing buildings, warehouses. the thickness of the slab is controlled as the requirement of fire resistance. formwork cost is high. sometimes difficult to install the electric equipment.
advantages and disadvantages of flat slabs a flat slab is a two-way reinforced concrete slab that usually does not have beams and girders, and the loads are transferred directly to the supporting concrete columns.
1-go to slab thickness and define your slab similar to this picture. 2-apply the loads and create the meshing and combinations then go to result maps and present the moment along the ribs then. and divide the moment consider from the map by spacing between the ribs then design it for top and bottom moment as t section .
the top of ribbed slab is normally thin and the bottom grid lines are generally ribs which are laid perpendicular to each other with equal depth. waffle slab has two directional reinforcement. all the ribs are directed from column heads or beams. the depth of ribs maintained is as same as depth of column head or beam.
the design principles of a solid slab bridge deck may be illustrated by the following illustrative example: illustrative example 1 : design a solid slab bridge superstructure having a clear span of 9.0 metres and carriageway of 7.5 metres with 1.5 metres wide footway on either side for a national highway.
slab design reading assignment chapter 9 of text and, chapter 13 of aci318-02 introduction aci318 code provides two design procedures for slab systems: 13.6.1 direct design method ddm for slab systems with or without beams loaded only by gravity loads and having a fairly regular layout meeting the following conditions:
in reality, sandwich slabs are ribbed slabs with a slab placed both to their upper and lower surface. sandwich slabs may have the disadvantage of a larger weight compared to the ribbed ones but on the other hand, they have the advantage that their spans and supports behave in the same proper way.
ribbed slabs one-way joists introducing voids to the soffit of a slab reduces dead weight and increases the efficiency of the concrete section. a slightly deeper section is required but these stiffer floors facilitate longer spans and provision of holes. economic in the range 8 to 12 m. the saving of materials tends to be offset by some
disadvantage of ribbed slabs: their construction is more challenging and therefore they require meticulous reinforcement detailing. a one-way simply supported ribbed slab, in the primary direction is composed by usual ribs while in the secondary direction the ribs are vertical and sparsely placed thus ensuring the even load distribution.
the thickness of slab over columns is also increased to support heavy loads and the thickened part of the slab is called drop panel. for lighter loads the column heads and drop panels are eliminated, such flat slab with constant thickness supported on prismatic columns are called flat plate. types of flat slab: 1 flat slab with drop panel.
purpose of waffle slab: waffle slabs provide stiffer and lighter slabs than an equivalent flat slab. the speed of construction for such slab is faster compared to conventional slab. relatively lightweight hence economical. it uses 30% less concrete and 20% less steel than a raft slab. they provide low floor deflections.
ribbed slab design spreadsheets to eurocode. ribbed slabs are widely used in many countries. this is attributed to the rapid shattering, ease of construction, and the reduction in the time of erection. this type of slabs or flooring system consists of series of small closed spaced reinforced concrete t-beams.
design a solid slab bridge superstructure having a clear span of 9.0 metres and carriageway of 7.5 metres with 1.5 metres wide footway on either side for a national highway. loading: single lane of irc class 70-r both wheeled and tracked or two lanes of irc class a whichever produces maximum effect:
advantages of ribbed and waffle slabs. in this type of slab, the tension stress is eliminated in the tension side of the slab. the strength of concrete in tension is very small and so elimination of much of the tension concrete is done by the use of pan forms. economical where the live loads are fairly small such as apartment houses, hotels.