Concrete construction materials

Concrete Construction Material for the Seventies, Construction Engineering Research Laboratory, Champaign, 111., May... 

Three other compounds of s-block elements—calcium oxide (CaO, known as lime ), sodium hydroxide (NaOH), and sodium carbonate (Na2 CO3)—are among the top 15 industrial chemicals in annual production. Lime is perennially in the top 10 because it is the key ingredient in construction materials such as concrete, cement, mortar, and plaster. Two other compounds, calcium chloride (CaCl2 ) and sodium sulfate (Na2 SO4 ), rank just below the top 50 in industrial importance. 

Dismantled construction materials such as used bricks, wood beams, and chunks of concrete... 

The device for examination of gas permeability of samples of constructive materials has been constructed. The device consists of compressor 1, receiver 2 with manometer 3, gates 4,5, holder 6 of concrete samples 7, flow meter of air 8 and vessel with gas 9 (Fig.l). The gate 5 adjusted the value of the gas pressure. In all experiments the pressure of gases in the receiver was 110 kPa. Air, Ar and 222Rn with concentration of 100 pCu/L in air were used as the gases. 

The gas permeability of the constructive materials after treatment by chemicals was examined. Influence of types of concrete, cement and gypsum, preliminary treatment by different chemicals, time between treatments by organic compounds, humidity of constructive materials, time between preparation of chemicals and treatment of materials (aging of chemicals), time between treatment of materials and testing (aging of treated materials) were investigated. 

For facilities susceptible to the contamination of nitroglycerin liquids and vapors, basic construction materials of wood framing, reinforced concrete, fiberglass reinforced plastic, and sandwich panels were chosen for development of architectural details incorporating lead conductive floor lining, equipment doors, personnel escape chutes and doors, ceiling and wall interfaces, interior finishes, joint sealing, door and wall louvers, wall vents, wall penetrations, and fixed windows. 

Reinforced concrete is the most commonly used construction material for structures designed to resist explosive blast loads. It is used extensively in blast hardened structures because of its strength, ductility (when properly designed), mass, penetration resistance, relative economy, and universal availability. Its strength, mass, and ductility provide high resistance to the extreme blast pressure (psi) and impulse (psi-ms) loads. It is important to remember that (unlike in static load design) in the... 

The results of this evaluation lead to the conclusion that a rectangular-based cubicle is the preferred room configuration. Additional parameter studies concluded that in the rectangular cubicle configuration, reinforced concrete is the preferred construction material over structural steel. Design of reinforced... 

Generally, cladding is needed to protect materials from corrosion in hostile environments, e.g., concrete in chemical plants. Two of the most widely used construction materials today are concrete and mild steel. There are, however, two things known for certain, namely concrete will crack, and steel will rust. 

Reinforced concrete is generally considered the most suitable and economical construction material for blast resistant buildings, especially for those close in to a... 

The major physical attributes of concrete as a construction material are a high compressive strength and stiffness, an ability to protect and restrain steel and, most important of all, to retain these properties over a considerable period of time. The effects that water-reducing admixtures have on these properties can be considered from the point of view of design parameters, i.e. those properties of concrete at a relatively early age (usually 28 days) which are used for structural calculations, and longer-term aspects or durability. 

The major physical attributes of concrete that make it a construction material of choice are its high compressive strength and stiffness and its... 

Non-dispersible concrete can be poured into a water-filled form without a tremie pipe to produce dense structural repairs. This type of material has particular advantages over conventional concrete both in terms of the quality of the repair produced and the reduction in placement cost associated with plant and diver manpower requirements. Field tests carried out on a commercially available AWA[46] show that bonding capability, pumpability and flowability around reinforcement are improved over conventional tremie-placed concrete. The quality and strengths of cores show AWA concrete to be suitable material for in situ structural concrete construction at considerable water depths [46]. 

Latex-modified mortars and concretes have become promising materials for preventing chloride-induced corrosion and for repairing damaged reinforced concrete structures. In Japan and the USA, latex-modified mortar is widely used as a construction material in bridge deck overlays and patching compounds, and for finishing and repairs [99]. Polymer-cement hydrate-... 

In this section, information on the operational aspects pertaining to the use of admixtures in the field is presented. In addition to details concerned directly with the physical aspects of batching and dispensing equipment and their operation, considerable attention is directed to the material-related problems that arise in the use of admixtures both in mainstream and special applications. It also offers guidance in the selection, use and control of uniformity of the product. Most of the issues discussed here apply equally to the three major fields of concrete construction, namely, site-batched and -placed concrete, ready-mixed concrete, and precast concrete. 

Sulphur concrete (without additives) will typically have a near-linear stress-strain curve up to failure, which occurs explosively at a strain usually between 0.0005 and 0.002. The peak stress varies from 20 to 70 MPa depending on the mix design. Sulphur concrete is thus a strong but brittle concrete material the brittleness need not necessarily be a grave disadvantage cast iron was used for a long period of time as a construction material. Any modification to the stress-strain behaviour should be evaluated carefully to see whether the modification is potentially useful. Two different approaches have been used to modify stress-strain behaviour. The modifications are (a) polymerization of the binder 04, j>, 17) and (b) use of the thermodynamically stable orthorhombic sulphur as the binder with alteration of the bond behaviour (3, 18). The matrices of both types of concrete are thus "modified" sulphur. 

Most metals, concrete, and other construction materials are corroded by hydrobromic acid. Suitable materials of construction include some fiber glass-reinforced plastics, some chemically resistant rubbers, PVC, Teflon, polypropylene, and ceramic-, rubber-, and glass-lined steel. Metals that are used include Hastelloy B, Hastelloy C, tantalum, and titanium. The Hastelloys can only be used at ambient temperatures. Liquid hydrogen bromide under pressure in glass at or above room temperature can attack the glass resulting in unexpected shattering. 

Building materials Road construction materials Other walls, roofing, tiles, bricks, concrete blocks, sheet glass sound barriers, signs, paving, guardrails, curbstones, crosswalk paint, surfaces of other structures paint, cement, solar panels ... 

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