It is a lightweight, precast building material that simultaneously provides structure, insulation, and fire and mold resistance. AAC products include blocks, wall panels, floor and roof panels, and lintels. It has been refined into a highly thermally insulating concrete-based material used for both internal and external construction. Besides AAC's insulating capability, one of its advantages in construction is its quick and easy installation, for the material can be routed, sanded, and cut to size on site using standard carbon steel bandsaws, hand saws, and drills. Even though regular cement mortar can be used, 98% of the buildings erected with AAC materials use thin bed mortar, which comes to deployment in a thickness of ⅛ inch. This varies according to national building codes and creates solid and compact building members. AAC material can be coated with a stucco compound or plaster against the elements. Siding materials such as brick or vinyl siding can also be used to cover the outside of AAC materials. Autoclaved aerated concrete
Transcript
It is a lightweight, precast building material that simultaneously provides structure, insulation,
and fire and mold resistance. AAC products include blocks, wall panels, floor and roof
panels, and lintels.It has been refined into a highly thermally
insulating concrete-based material used for both internal and external construction.
Besides AAC's insulating capability, one of its advantages in construction is its quick and easy
installation, for the material can be routed, sanded, and cut to size on site using standard carbon steel bandsaws, hand saws, and drills.
Even though regular cement mortar can be used, 98% of the buildings erected with AAC
materials use thin bed mortar, which comes to deployment in a thickness of ⅛ inch. This varies
according to national building codes and creates solid and compact building members.
AAC material can be coated with a stucco compound or plaster against the elements.
Siding materials such as brick or vinyl siding can also be used to cover the outside of AAC
materials.
Autoclaved aerated concrete
Asphalt concrete is a composite material commonly used in construction projects such as road surfaces, airports and parking lots. It
consists of asphalt (used as a binder) and mineral aggregate mixed together, then laid
down in layers and compacted. It is also increasingly used as the core for embankment
Biorock, also known as Seacrete, is a substance formed by electro-accumulation of minerals dissolved in seawater. The building process, popularly called accretion, is not to be confused with Biorock sewage treatment. The biorock building process grows cement-
like engineering structures and marine ecosystems, often for mariculture of corals,
oysters, clams, lobsters and fish in salt water. It works by passing a small electrical current
through electrodes in the water. The structure grows more or less without limit as long as
Fiber-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete
fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers and natural fibers. Within these different fibers that character of fiber-reinforced concrete changes with varying
concretes, fiber materials, geometries, distribution, orientation and densities.
Terrazzo is a composite material poured in place or precast, which is used for floor and
wall treatments. It consists of marble, quartz, granite, glass or other suitable
chips, sprinkled or unsprinkled, and poured with a binder that is cementitious, chemical or a combination of both. Terrazzo is cured, ground and polished to a smooth surface or otherwise finished to produce a uniformly
The reuse of hardened concrete as aggregate is a proven technology - it can be crushed and reused as a partial replacement for natural aggregate in new concrete construction. The hardened concrete can be sourced either from the demolition of concrete structures at the end of their life – recycled concrete aggregate, or from leftover fresh concrete which is purposefully left to harden – leftoverconcrete aggregate. Alternatively fresh concrete which is leftover or surplus to site requirements can be recovered by separating out the wet fines fraction and the coarse aggregate for reuse in concrete manufacture – recovered concrete aggregate. Additionally, waste materials from other industries such as crushed glass can be used as secondary aggregates in concrete. All theseprocesses avoid dumping to landfill whilst conserving natural aggregate resources, and are a betterenvironmental option.
Ductal is a proprietary pre-mixed ultra-high performance concrete whose physical characteristics exceed those of
common concrete used in the construction of buildings. It is manufactured by Lafarge and Bouygues. Ductal has high compressive strength and flexural resistance compared to
other concretes. It also has high durability, abrasion resistance, and chemical/environmental resistances (e.g.
freeze and thaw, salt water, etc.). Due to these properties, Ductal can be used in thinner cross-sections and in more
varied applications than common concrete. Ductal is almost self-placing and is best suited for precast elements or in-
situ repair or upgrade works. The constituents of Ductal are cement; fine sand, silica fume and silica flour as a filler,
additive and water, using a low water cement ratio and may include high-strength steel fibers or non-metallic fibers.
Ductal is a ductile material that possesses ultra-high compressive strength, high tensile strength and high
durability together with high fatigue performance. It also has excellent impact, blast and abrasion resistance. The type and quantities of special materials used in Ductal
result in a superior material that can provide innovative and valuable solutions for a wide range of applications; it is
not a replacement for ordinary concrete in applications that do not exploit its unique properties and requires
The use of superplasticizers (high range water reducer) has become a quite common practice. This class of water reducers were originally developed in Japan and Germany in the early 1960s; they were introduced in the United States in the mid-1970s. They allow for increased workability without the addition of any additional water.Superplasticizers are linear polymers containing sulfonic acid groups attached to the polymer backbone at regular intervals (Verbeck 1968). Most of the commercial formulations belong to one of four families:Sulfonated melamine-formaldehyde condensates (SMF)Sulfonated naphthalene-formaldehyde condensates (SNF)Modified lignosulfonates (MLS)Polycarboxylate derivatives
Synthetic-fiber reinforcement to reinforce concrete in non-structural applicationsSynthetic-fiber reinforcement prevents cracks in concrete, unlike WWF, which controls crack width -- cracks actually need to occur before the WWF goes to work. Small-diameter synthetic fibers (nylon, glass, steel or polypropylene) are now being added to concrete to reduce shrinkage cracking by more than 80% according to independent lab tests. Reducing cracks improves concrete impermeability, increases its toughness and long-term weatherability, and can reduce callbacks in concrete slab floors, decks, driveways, and walks. According to fiber manufacturers, the placement, curing, or finish characteristics of the concrete are not affected by the addition of fibrous reinforcement.
The majority of regular concrete produced is in the density range of 150 pounds per cubic foot (pcf). The last decade has seen great strides in the realm of dense
concrete and fantastic compressive strengths (up to 20,000 psi) which mix designers have achieved. Yet regular concrete has some drawbacks. It is heavy, hard to work with, and after it sets, one cannot cut or nail into it without some
difficulty or use of special tools. Some complaints about it include the perception that it is cold and damp. Still, it is a remarkable building material - fluid, strong, relatively cheap, and environmentally innocuous. And, it is available in almost
every part of the world.Regular concrete with microscopic air bubbles added up to 7% is called air
entrained concrete. It is generally used for increasing the workability of wet concrete and reducing the freeze-thaw damage by making it less permeable to
water absorption. Conventional air entrainment admixtures, while providing relatively stable air in small quantities, have a limited range of application and
aren't well suited for specialty lightweight mix designs.Lightweight concrete begins in the density range of less than 120 pcf. It has
traditionally been made using such aggregates as expanded shale, clay, vermiculite, pumice, and scoria among others. Each have their peculiarities in
handling, especially the volcanic aggregates which need careful moisture monitoring and are difficult to pump. Decreasing the weight and density
produces significant changes which improves many properties of concrete, both in placement and application. Although this has been accomplished primarily
through the use of lightweight aggregates, since 1928 various preformed foams have been added to mixes, further reducing weight. The very lightest mixes
(from 20 to 60 pcf) are often made using only foam as the aggregate, and are referred to as cellular concrete. The entrapped air takes the form of small,
macroscopic, spherically shaped bubbles uniformly dispersed in the concrete mix. Today foams are available which have a high degree of compatibility with many of the admixtures currently used in modern concrete mix designs. Gecko
Stone of Hawaii is currently experimenting with one such foam. Foam used with either lightweight aggregates and/or admixtures such as fly ash,
silica fume, synthetic fiber reinforcement, and high range water reducers (aka superplasticizers), has produced a new hybrid of concrete called lightweight
Polymer concrete is part of group of concretes that use polymers to supplement or replace cement as a binder.
The types include polymer-impregnated concrete, polymer concrete, and polymer-Portland-cement
concrete. In polymer concrete, thermosetting resins are used as the principal polymer component due to their high thermal stability and resistance to a wide
variety of chemicals. Polymer concrete is also composed of aggregates that include silica, quartz,
granite, limestone, and other high quality material. The aggregate must be of good quality, free of dust and other debris, and dry. Failure of these criteria can
reduce the bond strength between the polymer binder and the aggregate. Polymer concrete may be used for
new construction or repairing of old concrete. The adhesion properties of polymer concrete allow
patching for both polymer and cementitious concretes. The low permeability of polymer concrete allows it to
be used in swimming pools, sewer pipes, drainage channels, electrolytic cells for base metal recovery, and other structures that contain liquids. It can also be used
as a replacement for asphalt pavement, for higher durability and higher strength.
Cellular Concrete products are lightweight materials produced by blending a cementitious slurry with a
stable, three-dimensional pre-formed foam meeting ASTM C869. The foam is produced by diluting a liquid concentrate with water, then pressurizing it with air
and forcing it through a conditioning nozzle. The foam is then blended with a base mix consisting of cement, fly ash, water and sometimes aggregate. This causes
the base mix to expand and become lighter. This engineered, open-cell lightweight material is capable of
reducing loads without disturbing or re-directing natural water flow. The air bubbles hold their shape
until the cement hydrates permanently trapping the air in the material. The density and strength of the
material is a function of the mix design. While specific Geofill product performance characteristics will vary, all
Geofill cellular concrete products offer these substantial benefits:
Low Density/Lightweight - Lateral or vertical load reduction can be achieved without reducing strength or stability. Densities range from 15 to 120 pounds per cubic foot.
High Bearing Capacity - Lightweight, yet stronger than soils or compacted fills.
Extremely Pumpable - High air content makes it easy to pump Geofill materials long distances at low pressures.
Highly Flowable - Self-leveling and will flow into and fill any void.
Compaction - No compaction is necessary. Use this product when future settlement cannot be tolerated.
Thermal Insulating Properties - Provides good insulating qualities.
Energy Absorbing - As cellular concrete is compressed during impact, resistance increases and kinetic energy is absorbed.
