Aug 02, 2017 build house with concrete hollow blocks laying cement brick constriction engineer build house duration. A structural topping can increase that up to a 4hour rating. At 75% utilisation of the capacity, productions of 600000 nos. This weight per unit area depends on the type of finishing which is usually made of. Details are available in both adobe acrobat reader pdf and cad dxf format. Additional reinforcement can be incorporated into hollowcore slabs to accept bolt. Find the following parameters for design moments in step 2 per unit width step 4 note.
The topping may increase the flexural strength, shear strength, and bending stiffness of the slab if. To further increase the strength, the slabs are reinforced with 12mm diameter steel strand, running longitudinally. Since its establishment in 1988, hollow core concrete pty. Hollow core slabs are prestressed concrete elements that have a constant cross section. It is generally used in the construction of floors for highrise apartments or multi storey buildings. Hollowcore slabs lajes alveolares machinery and equipment for hollow core slabs maquinas e. Cement concrete hollow blocks are usually of the following three dimensions. Twoway joist concrete slab floor waffle slab system. Hollow blocks are the most common type of concrete blocks, having one or more holes that are open at both sides.
A hollow core slab refers to a precast slab that is prepared using prestressed concrete. Hollowcore slab precast concrete flooring manufacturers. Bubble deck slab seminar report, ppt, pdf for civil. Not only do these cores decline slab selfweight and increase structural efficiency but also act as service ducts. Proper curing increase compressive strength of the blocks.
Jun, 2016 precast concrete house 1,215,478 views 6. Hollow blocks have a minimum crushing strength of 3. Hollowcore plank is resistant to nature from termites or hurricanes to high winds and seismic events. Copeland is colorados goto source for all your precast concrete needs. The reinforced solid slab and hollow core slab is designed as per is 4562000. Browse our selection of precast concrete slabs for your next project. It is suitable for cases where fast constructions are desired.
Lafarge precast concrete hollowcore slabs are produced at our edmonton facility, for the majority of projects the standard production process comprises of a combination of prestressed strand combined in the with the 8, 10 or 12 finished high strength concrete. Reinforced concrete sk 33 section through slab showing stress due to moment. The idea was to create a hollow biaxial slab with the. These methods are used in completing the field condition survey of buildings. This design value of load t and deflection is compared with experimental value by testing the slab. The lateral loads are independently resisted by shear walls. To replace the superfluous concrete, a hdpe hollow spheres are used in the centre of slab. Compared with an ordinary reinforced concrete slab with the same capacity, a prestressed concrete hollowcore slab could save 40% to 50%. Compared with an ordinary reinforced concrete slab with the same capacity, a prestressed concrete hollow core slab could save 40% to 50%. They are manufactured using high tensile strength prestressed strands. Specimens where the core fill concrete remained composite with the slab concrete following webshear failure had the highest webshear strengths, which indicated that bond between the core fill concrete and slab concrete is a critical factor in the shear. To obtain a higher slab thickness, normal carbonate concrete field topping can be added to gain a higher total slab thickness.
Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems. The units themselves are manufactured at a width of 1200mm and depths of 150, 200, 250, and 300mm. Precast concrete hollowcore slabs lafarge precast edmonton. The good concrete compacted by high pressure and vibration gives substantial strength to the block. Hollow core slabs are the most widely used type of precast flooring. Encons precast concrete hollowcore offers many benefits at a costeffective price. Hollowcore can be used in virtually any building application that calls for strength, durability and speed of construction and is a crucial part of the structural integrity in multifamily residential, manufacturing and recreational facilities, retail, schools, municipal and commercial buildings. Saccoman, chairperson james beerbower ernest markle kevin boyle james markle jeffrey butler milo j. Shear capacity of hollowcore slabs with concretefilled cores. In order to view pdf documents, you must have adobe acrobat reader installed. Hollowcore slabs with castinplace concrete toppings. Manufacturing process cement concrete blocks can be solid dense or hollow. A hollow core slab is a precast pre stressed concrete member with continuous voids provided to reduce weight and cost.
Adobe acrobat reader is free and can be downloaded here. Hollow slabs with innovative types of voids manmade. The slab is very important structure member in building and slab is one of the largest member consuming concrete. Sep 03, 2011 reinforced concrete sk 33 section through slab showing stress due to moment. Maximize space in any house plan with hollowcore roof and floor systems. Advantages prestressed hollow core slabs are among the most advanced products in the precast concrete industry, especially with regard to their high quality and low consumption of materials. Experimental evaluation of concrete slab using hollow steel pipes. When the load acting on the slab is large or clear span between columns is more, the slab thickness goes on increasing. Design of slab for flexure 067 m unit width of slab. But it was used only in one way spanning construction, and must be supported by beams and or fixed walls. Besides different sizes and designs can be given to the blocks. Concrete slab types construction, cost, and applications. The topping may increase the flexural strength, shear strength, and bending stiffness of.
Other topping materials such as gypcrete can be added to achieve a fire endurance using different tables. Firstly cement, stone chips, sand, etc are mixed in the ratio of 1. Shear strengthening of prestressed concrete hollowcore slabs. Hollow core concrete concrete acoustic noise barriers. Specimens where the core fill concrete remained composite with the slab concrete following webshear failure had the highest webshear strengths, which indicated that bond between the core fill concrete and slab concrete is a critical factor in the shear strength of hollow core slabs with filled cores. Twoway joist concrete slab floor waffle slab system analysis and design design the concrete floor slab system shown below for an intermediate floor with partition weight of 50 psf, and unfactored live load of 100 psf. Fire ratings will also be improved if the plank assembly is restrained against thermal expansion. Often, the space beneath a garage can be exploited by extending the basement walls to include the garage overhead. Precast concrete constructions are cost effective, quick to assemble and build.
As more residential covenants dictate restrictions, hollowcore helps home owners gain more usable space. Bolted connections under hollow core slabs, steel beam. This increases the concrete crosssectional area without interfering with the hollow core slab production that is, without affecting. Bolted connections under hollowcore slabs, steel beam. Field testing of concrete structures include nondestructive testing and destructive testing. In many domestic and industrial buildings, a thick concrete.
In practice, a concrete topping layer is often cast in place onto the top surface of hollowcore slabs to create a continuous level finished surface. Pdf performance of prestressed hollowcore slabs with and. Hollow core stubbes precast concrete, cement and redimix. Low maintenance, color and brilliance of masonry withstands outdoor elements. Advantages prestressed hollowcore slabs are among the most advanced products in the precast concrete industry, especially with regard to their high quality and low consumption of materials. In many domestic and industrial buildings, a thick concrete slab. By using tower cranes hollow slabs are inserted between the beams. The total void area can amount to 50% of the gross crosssectional area. Hollowcore residential applications county materials. Bending stresses in the bubble deck slab are found to be 6. Setting hollowcore slabs on bearing walls forms the necessary fire separation and the perfect noise barrier.
Hollow core plank technical guide temperatures are based on the amount of concrete cover and the standard fire exposure as defined by the timetemperature relationship specified in astm e119. Design precast structural concrete, including comprehensive. The use of precast concrete hollowcore flooring is a highly cost effective solution that fits easily into any structural system such as steel or concrete frame or indeed masonry construction. Pci manual for the design of hollow core slabs second edition by donald r. They are primarily used as a floor deck system in residential. Hollow core slab technical sheets hollow core technical sheets should be used for guidance only and consultation with hollow core concrete should be made prior to proceeding. The first is by using lightweight aggregate concrete and the second is obtained through changing the geometry of cross sectional area of slabs for example hollow core slabs and ribbed slab. Create extra living and storage space by using a homes entire footprint, even neglected space available under a garage, porch or stoop.
Concrete does not burn and can never be turned off or malfunction. Dxf files can be imported directly into many common cad programs. Details hollowcoredetails hollowcore just click below to download a pdf or dwg detail. Shear strengthening of prestressed concrete hollowcore. Strengthening of prestressed hollow core slabs are required for several reasons to. Hollowcore slab benefits of using hollowcore floor slabs. Prepared for the pci hollow core slab producers committee john e. Steelreinforced slabs, typically between 100 and 500 mm thick, are most often used to construct floors and ceilings, while thinner mud slabs may be used for exterior paving see below.
Hollow core slab properties prop imperial metric a 256. Shear capacity of hollowcore slabs with concrete filled cores. Advantages building element wall size various sizes mixing ratio 1 cement. Sounding involves striking the concrete surface and interpreting the sound produced. Destructive and nondestructive field testing of concrete. In practice, a concrete topping layer is often cast in place onto the top surface of hollow core slabs to create a continuous level finished surface. It is a type of precast slab through which cores are run. A concrete slab is a common structural element of modern buildings, consisting of a flat, horizontal surface made of cast concrete. This book or any part thereof may not be reproduced in any form without the written permission of the pre castprestressed concrete institute.
Height of hollow block, h mm topping to be placed on top of hollow blocks, t mm 01 0635 as 510. The slab is very important structure member in building and slab is one of the largest member consuming concrete 2. Pci manual for the design of hollow core slabs and walls. Melbourne manufacturers and installers of hollow core precast concrete for building. Hollow core slab properties prop imperial metric a 290. The most common method of nondestructive field testing is through a process called sounding.
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