For reinforced concrete buildings, there are several types of cost-effective floor systems (slabs) that almost meet all loading and span requirements. The topic of choosing cost-effective floor solutions that can withstand design requirements is examined. Reinforced concrete offers a wide range of structural options for a variety of applications, including residential, office, and industrial structures. Because the cost of the floor system is such a large part of the structural cost, choosing a low-cost floor system will effect the project’s overall cost. Building type, architectural layout, span length between columns, and aesthetic characteristics are all aspects that influence the economics of floor systems. This article will provide advice for selecting floor solutions that are cost-effective.
Concrete Floor Systems for Buildings and Structures
Slab Floor System with Flat Plates Flat plate systems are supported directly by columns and have a span of 6-8 metres with a life load of 3-5 KN/m2. This type of floor system is commonly used in hotels, hospitals, and multifamily housing. Flat plates have several notable advantages, including quick construction, easy and minimal formwork costs, and a flat ceiling that lowers finishing costs. When flat plates are utilised in building construction, the total height of the structure can be reduced, which is advantageous from an economic standpoint. Because the total building height is reduced, vertical runs of cladding, partition walls, mechanical systems, plumbing, and many other construction items are reduced. Another benefit of flat plates is that they offer for more flexibility in design.
Building Systems with Flat Slabs Flat slabs are similar to flat plates, with the exception of the thickness of flat slabs around columns, which is supplied to improve the floor system’s shear capacity. Flat slabs are cost-effective for spans of 6 to 9 metres and live loads of 4 to 7 KN/m2.When punching shear force prevents the use of flat plates, this sort of floor solution is ideal, especially when relatively shallow slabs are required. It should be noted that thickening the floor system around columns (drop panels) raises formwork costs. For the same span length, the thickness of a flat slab is 10% less than that of a flat plate. The dimensions of drop panels were regulated by the ACI code.
Formwork, concrete material placement and finishing, and steel placement are said to account for 47 percent, 36 percent, and 17 percent of the entire floor cost for flat slabs, respectively.Building Systems with Flat Slabs Flat Slab Floor System (Fig. 2)Slabs of Waffle It is made up of a reinforced concrete slab and a waffle slab that is evenly distributed in two directions. To offer shear resistance in the column area, the slab around the columns is solid. Waffle slabs are cost-effective for spans of 9 to 15 metres and live loads of 4 to 7 KN/m2. Although this floor system’s ultimate load carrying capability is larger than that of flat slabs, the cost of its formworks is significantly higher.
Beams on Slabs This sort of floor system is cost-effective for spans of 6 to 9 metres and live loads of 3 to 6 KN/m2.The beam increases the relative stiffness of the floor system, reducing deflection, but increasing the expense of formwork due to beam formwork.Beams on Slabs on Beams Slab on Beams with One-Way Access This sort of floor system is ideal for spans of 3 to 6 metres and live loads ranging from 3 to 5 kg per square metre. This span range can be expanded at the cost of slightly higher deflections and floor system costs. Slab on Beams, One-Way Beams with a One-Way Slab Floor System with One-Way Joists it is made out of concrete ribs that are evenly placed and span the length of the building.
Various Types of In-situ Concrete Floor Systems
This floor system has various advantages, including being cost effective for long spans with heavy loads, requiring no additional depth for utility installation because they can be installed between joists, and reducing self-weight. According to reports, the cost of formworks accounts for around 51% of the entire cost of the floor system. Floor System with One-Way Joists Floor System with One-Way Joists Continue reading: A flat plate is a one- or two-way system that is normally supported directly on columns or load bearing walls. It is one of the most prevalent types of building floor construction. The flat plate floor’s main characteristic is a uniform or nearly uniform thickness with a level soffit that requires just simple formwork and is straightforward to install. Horizontal services can be located above a suspended ceiling or in a bulkhead because to the floor’s flexibility.
Building floor systems exist in a variety of sizes, shapes, and styles. There are so many variables in a floor system, such as varied spans, offset spans, cantilevers, and the level of continuity, as well as the impacts of beams, columns, and walls on the slab system, that it’s difficult to cover all scenarios in a small number of charts. With the variety of sophisticated computer packages now available for concrete floor design, it is strongly recommended that once a floor system and initial sizes have been determined, a series of trial runs be performed as part of the preliminary design process to determine the appropriate thicknesses and details. Slab that is flatA one-way or two-way system with thickenings in the slab is known as a flat slab.
Another type of in-situ floor is the flat-plate floor, which consists of a solid reinforced slab supported by concrete columns and forms a monolithic structure. The slab (or plate) functions as an elastic diaphragm bearing on point supports and usually incorporates reinforcement throughout its whole area.When compared to beam and slab construction, flat-plate floors require less shuttering and reinforcing and are lighter. Their continuous soffit also enables for the same height partitions, which is especially handy for office partitioning.Floors with in-situ T-beams These include simultaneously casting a sequence of parallel, reinforced T-beams with the slab, resulting in a monolithic structure with ribbed soffit. Although the end form is lighter than a solid slab floor, it is more expensive due to the proprietary nature of the process.
These floors are more lightweight than solid slab floors and have a flat soffit. They are supported by temporary formwork or shuttering and are based on a T-beam arrangement created by laying hollow clay or concrete blocks end-to-end to form continuous T-beams. The voids between the blocks are reinforced, and concrete is poured over the structure, resulting in a monolithic slab and T-beam structure. The concrete is poured to form a structural topping, which is the thickness of concrete above the block’s top level. Waffle slabs are made out of a rectangular grid of intersecting beams formed by pouring concrete in between square-box moulds after reinforcement has been installed. The end result could be.
Concrete flooring that have been pre-stressed
Concrete floor components that have been pre-stressed can minimise floor thickness and deadweight while also increasing the economic span. Pre-tensioning of beams in the factory is the most frequent approach, however post-tensioning can also be utilised with specific systems and can be done in the factory or on site. A structural concrete topping is poured in situ after the pre- or post-tensioned beams have been set down with reinforcement to make a monolithic, composite structure. Planks that have been pre-tensioned Individual strips of concrete slab, relatively thin and frequently incorporating hollows to minimise weight, are what pretensioned planks are. They are normally laid side by side to form a continuous shuttering and working platform, supported by loadbearing walls or beams; the structural concrete topping is then applied.
concrete on steel joists, concrete on steel deck, concrete slab and joist, and precast concrete.
Flat slab structure is more economical than that of conventional slab structure.
Reinforced concrete floors are a type of formwork found in the construction industry.