Structural lightweight concrete has an inplace density unit weight on the order of 90 to 115 lb ft. The information is based on many laboratory studies and records of a large number of existing structures that have provided satisfactory service for more than 85 years. City mix ultra lightweight gfrc aggregate glass fiber reinforced concrete. Polystyrene light weight concrete nonstructural specified by density lowest density 450kgm3 35mpa cement type 100% opc where available aggregate size. Choice of tool used in finishing is determined by the finish desired. High absorption rates and rough texture prohibit the accurate determination of the bulk specific gravity of lightweight aggregates. City mix ultra lightweight gfrc aggregate glass fiber. Pumping lightweight concrete can be achieved, but care needs to be taken so that the concrete mix doesnt separate. Nearly all fct tests on all three girder mixes gave splitting ratios that were greater figure 1.
The concrete mixture is made with a lightweight coarse aggregate. Study of lightweight concrete behaviour lightweight concrete can be defined as a type of concrete which includes an expanding agent in that it increases the volume of the mixture while giving additional qualities such as nailbility and lessened the dead weight. Lightweight aggregates are used as insulating fill within the cavities of concrete masonry units to decrease. Apr 12, 2018 lightweight concrete foamed concrete, aac, etc.
Depending on its composition, lightweight concrete can be conveyed by means of conventional concrete pumps or delivered in readymix concrete trucks. For mix design of structural lightweight concrete, standard practice for selecting proportions for structural lightweight concrete aci 211. Suggested mix proportions for norlite structural lightweight concrete watercement ratio. The design properties of lightweight concrete are not covered in aci 31819. Researchers have supported the need to present mix design data in form of graphs or equations hover, 1995. Lightweight concrete reduces transport costs and enables faster work. Cellular lightweight concrete materials, applications and. Foamed concrete is manufactured by mixing portland cement, sand, fly ash, water and preformed foam in varied proportions. Lightweight concrete lightweight concrete by cemex incorporates advanced admixture technology with a special aggregates to produce mixes with much lower densities than normal concrete. Cellular lightweight concrete clc also known as foamed concrete is one of the most significant type of concrete used for construction purposes due to its various advantages and usages over traditionally produced concrete. The slwac mix design is more complex than that of normal weight concrete as more parameters need to be determined. Structural lightweight concrete has an inplace density unit weight on the order of 90 to 115 lb ft3 1440 to 1840 kgm3 compared to normalweight concrete with a density in the range of 140 to 150 lb ft3 2240 to 2400 kgm3. Aug 12, 2016 city mix is designed to replace the sand in glass fiber reinforced gfrc backcoats, reducing weight by 25% to 50%. Lightweight aggregate stockpiles with continuous sprinklers.
Pdf lightweight concretes are widely accepted in the construction industry mainly due to its low density. Dudley, ray wetherholt, zen szewczyk, and herb cannon lightweight. Understanding different types of lightweight concrete by jason spangler the use of lightweight concrete dates back to as early as the eighteenth century, and as advances in building and construction technology have increased, so has the use of lightweight concrete as the benefits of lighter dead load concrete have become apparent. Equations for mix design of structural lightweight concrete 3 guide the mix designer, it is thought worthwhile to add more values to these data for convenience of the users. Lightweight concrete is not as strong as traditional concrete as adding the aggregate to the mix weakens the bonds, making it less sturdy when it comes to holding up weight. Batching of lightweight concretes is normally done from readymixed concrete producers. After leveling, allow concrete to set until all bleed water has evaporated before troweling. The problems most frequently encountered in designing a lightweight concrete mix are maintaining workability while minimizing unit water content, and establishing availability of mix water for hydration. Mix designs structural concrete norlite lightweight aggregate. Typically, properties of lightweight concrete have been compared with those of. Designing a lightweight structural concrete mix concrete. This product guide contains various mix designs for lightweight concrete, utilizing perlite as the primary aggregate. Proportioning structural lightweight aggregate concrete escsi.
For applications requiring at least 2 inches in thickness. At low workabilities, the concrete can easily be placed by skip or chute. In some cases a portion or the entire fine aggregate may be a lightweight product. How to make lightweight concrete using styrofoam hunker. Method a, consists of mixing a preformed foam surfactant or mix foaming agents mixture into the cement and water slurry. As a result, lightweight concrete should not be used in place of regular concrete for most projects. Promix lightweight concrete mix is a quality mixture of sand, lightweight coarse aggregate and cement, designed and engineered for repairs and applications where typical concrete weight would pose a problem. Aci mix design as used for normal weight concrete and mix design methods as used for lightweight concrete were employed to obtain the target compressive strength at 28day and was found to be.
If a calculated blend contains too much or too little lightweight or mediumweight aggregate, the desired density might not be achieved. This guide gives basic mix designs, which may be used as stated, or as a starting point for your own custom mixes. A simple mix design method for structural lightweight. The lightweight concrete density is less because lightweight coarse aggregates and sometimes lightweight fine aggregates are used, which make the concrete weigh less. Mix design of lightweight selfconsolidating concrete using new zealand pumice jamal almulla wilco precast ltd summary pumice is a volcanic aggregate that has been used to produce lightweight concrete for many. The design properties of lightweight concrete are discussed in aci 2r guide for structural lightweightaggregate concrete. Lightweight concrete what is lightweight concrete and how.
Lightweight concrete can be defined as a type of concrete which includes an expanding agent in that it increases the volume of the mixture while giving. Structural lightweight concrete has an inplace density unit weight on the order of 90 to 115 lb ft 3 1440 to 1840 kgm compared to normalweight concrete with a density in the. The mix design techniques described above can be used to design mixes for normalweight, mediumweight, and lightweight units. The equations are also useful for mixture proportioning adjustment. Mix design and properties of fly ash waste lightweight. There are a wide range of publications about lwc concerning different light weight aggregates and mix proportions. Advantages and disadvantages of lightweight concrete giatec. May 09, 2018 lightweight concrete may not be as structurally sound as traditional concrete, but it can be useful in some projects where weight is more important than strength.
Air content of structural lightweight concrete must be closely monitored and controlled to ensure that the density requirements are being achieved. Extra care should be taken when designing lightweight and mediumweight mixes. That portion absorbed by the aggregate is not considered for determining yield since it has no volumetric effect. Cip 36 structural lightweight concrete what is structural lightweight concrete. Understanding different types of lightweight concrete. Mean concrete properties from tests on 4 by 8inch 102 by 203mm cylinders.
That portion absorbed by the aggregate is not considered for determining. In recent years, some efforts have been made to combine the advantages of these two types of concrete in one package called lightweight selfcompacting concrete lwscc. Pdf development of lightweight concrete for structural. Pdf rational mix design of lightweight concrete for. Jun 17, 2018 this video animation, animated video explains the concept of lightweight concrete. The mix designs in the following pdf are based upon an estimated active water demand. Current design methods for structural lightweight aggregate concrete slwac are usually only valid for a limited range of concrete compositions that have previously been subjected to trial tests. It is commonly manufactured by two different methods. Pdf on dec 4, 2008, eethar thanon dawood and others published rational mix design of lightweight concrete for optimum strength find. This code contains tables and graphs to serve as a guide in the process of selection of mix ingredient of concrete. Lightweight concrete this chapter covers some of the physical properties of lightweight concrete. The concrete mixture can be proportioned with combinations of normalweight and lightweight coarse and fine aggregates to achieve the desired equilibrium.
To make this concrete, combine 8 parts cement, sand and lightweight aggregate with 5 parts water. Structural lightweight concrete containing sintered fly ash lightweight aggregates were produced. Learn more about the advantages and disadvantages of lightweight concrete. Cip 36 structural lightweight concrete what is structural lightweight concrete structural lightweight concrete has an equilibrium density ranging from 90 to 120 lbft3 31440 to 1840 kgm compared to normalweight concrete with a density in the range of 140 to 150 lbft 3 2240 to 2400 kgm. A structural lightweight concrete mix has a density of about 105 pounds per cubic foot compared to normal concrete with a density of 150 pounds per cubic foot. Pdf rational mix design of lightweight concrete for optimum strength. After placing lightweight concrete, puddle the mix with a stick or rod to eliminate any voids in the material. Pdf experimental study on lightweight aggregate concrete. Lightweight insulating concrete a s a c h o i c e re ro o f i n g s y s t e m by hubert t. Equations for mix design of structural lightweight concrete. Structural concretes of up to 50nmm2 compressive strength can be produced with a dry density of 1900kgm3 and non structural mixes can be produced with. All the concretes have densities less than 2000 kgm 3 a new mix design methodology was proposed and has the capability to produce compressive strength up to 70 mpa. This chapter focuses on several applications of lightweight aggregate concrete lwac. It is possible to develop light weight concrete of density up to 1450 kgm 3 using.
Concrete mix designed for general applications and made with light weight aggregates. Mix designs structural concrete norlite lightweight. These products, although both are lightweight have several important differences and these must be noted before ordering. Lightweight concrete mixture is made with a lightweight coarse aggregate and sometimes a portion or entire fine aggregates may be lightweight instead of normal aggregates. Lightweight concrete, light weight concrete civil engineering animated videos, civil engineering videos. Chapter 4 proportioning structural lightweight concrete. Taking this into account, a simplified design method is proposed for slwac made with.
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