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How do you specify lightweight concrete?

How do you specify lightweight concrete?

Lightweight concrete can be specified using the notation LC for the strength class, e.g LC30/33, which denotes a lightweight concrete with a cylinder strength of 30MPa and a cube strength of 33MPa. The lighter the concrete, the greater are the differences to be accounted for in the properties of the concrete.

What aggregate is used in lightweight concrete?

Lightweight aggregates such as diatomite, pumice, vermiculite, and perlite are typically used in conventional concrete. Bottom ash, crushed clay brick (RCB), and waste tire rubber are recycled aggregates and can also be used as lightweight aggregates in lightweight geopolymer concrete.

What is Lambda for lightweight concrete?

(Dr. Mohammed E. Haque, P.E.) φ = 0.75; λ = 1 for normal weight concrete; 0.85 for sand-lightweight concrete; 0.75 for all lightweight concrete.

What are the properties of lightweight concrete?

Lightweight concrete is characterized by good compressive strength, durability and the most important advantages – low density and improved properties of thermal conductivity. Typical lightweight concrete aggregates are expanded clay or shale, natural porous materials like vermiculite or pumice.

Is lightweight concrete strong?

Structural lightweight concrete has an in-place density of 90 to 115 lb/ft³, whereas the density of regular weight concrete ranges from 140 to 150 lb/ft³. Nevertheless, a higher compressive strength of 7000 to 10,000 psi can be attained with lightweight concrete.

What is lightweight concrete called?

Foam concrete
Foam concrete, also known as Lightweight Cellular Concrete (LCC), Low Density Cellular Concrete (LDCC), and other terms is defined as a cement-based slurry, with a minimum of 20% (per volume) foam entrained into the plastic mortar.

What is a lightweight concrete?

Lightweight concrete is a mixture made with lightweight coarse aggregates such as shale, clay, or slate, which give it its characteristic low density. It is being increasingly used to build sleek foundations, and has emerged as a viable alternative to regular concrete.

What is lambda in ACI?

Lambda, λ is the lightweight concrete modification factor. This factor only applies to the ACI 318-14, ACI 318-11, ACI 318-08 and CSA A23.

Is lightweight concrete expensive?

Is lightweight concrete more expensive than normal weight? Yes and no. The material unit cost of lightweight concrete is typically higher than that of normal-weight concrete, but the unit cost usually is more than offset by the overall reduction in concrete volume and steel tonnage for the structural system.

What are the disadvantages of lightweight concrete?

Disadvantages of Lightweight Concrete: The only drawback of lightweight concrete is that the depth of carbonation i.e. the depth within which corrosion can occur under suitable conditions is nearly twice than that of normal concrete.

Is lightweight concrete more expensive?

Does light weight concrete crack?

A new report by the Virginia Transportation Research Council in the USA has shown that lightweight concrete decks exhibit fewer cracks than their conventional counterparts.

How are design requirements of concrete based on ACI 318-19?

It is calculated using equations that are provided by ACI 318-19 Code or testing. There are differences between values obtained from equations and those achieved from testing. However, the theoretical values from equations are suitable for the majority of structures.

Is the ACI code restricted to PCI code?

At present my library is restricted to the ACI code and the PCI code. The ACI 318 commentary (R11.2.1.2) states that “the multipliers are based on data from tests of many types of structural lightweight aggregate concrete”.

What are the safety factors of lightweight concrete?

I would guess that these factors are derived from a statistical analysis of empirical tests on typical lightweight concrete (85-120 pcf) and result in a comparable factor of safety as normal weight concrete provisions.

What are the building code requirements for concrete?

There are several requirements established in ACI 318-19 (Building Code Requirements for Concrete and Commentary) that concrete materials need to meet; otherwise, it would not be suitable for the construction of a structure. These requirements vary from one structure to another one. They include minimum permissible concrete compressive strength