Glassfibre-reinforced gypsum (GRG) combines the non-combustibility of gypsum plaster with the reinforcing strength of glass fibres. Products contain typically 5% of the standard E-glass fibres, which considerably improve impact as well as fire resistance. Commercial GRG products are available as standard panels, encasement systems for the fire protection of steel and decorative wall panels. As …
Glassfibre-reinforced concrete (GRC) is a material that was developed in the early 1970s by the Building Research Establishment. The standard material is produced from a mixture of alkali-resistant glass fibres with Portland cement, sand aggregate and water.Admixtures such as pozzolanas, superplasticisers and polymers are usually incorporated into the mix to give the required fabrication or …
Metamorphic rocks are formed by the recrystallisation of older rocks, when subjected to intense heat or pressure or both, within the earth’s crust. Clay is metamorphosed to slate, limestone to marble and sandstone to quartzite Slate Slate is derived from fine-grained sand-free clay sediments. The characteristic cleavage planes of slate were produced when the clay …
Sedimentary rocks are produced by the weathering and erosion of older rocks. In the earliest geological time these would have been the original igneous rocks, but subsequently other sedimentary and metamorphic rocks too will have been reworked. Weathering action by water, ice and wind breaks the rocks down into small fragments which are then carried …
Sedimentary rocks are produced by the weathering and erosion of older rocks. In the earliest geological time these would have been the original igneous rocks, but subsequently other sedimentary and metamorphic rocks too will have been reworked. Weathering action by water, ice and wind breaks the rocks down into small fragments which are then carried …
Rainscreen cladding is the external weathering element to multi-layer rainscreen wall systems. The rainscreen façade is drained and back-ventilated to protect the structural wall from the adverse effects of the sun, wind and rainwater. The design of the joints and the cavity between the façade and the structure result in an equalisation of air pressure …
Modern glass is manufactured from sand (silica), soda ash (sodium carbonate) and limestone (calcium carbonate), with small additions of salt-cake (calcium sulphate) and dolomite (magnesian limestone). This gives a final composition of typically 70–74% silica, 12–16% sodium oxide, 5–12% calcium oxide, 2–5% magnesium oxide with small quantities of aluminium,iron and potassium oxides. The addition of …
Green walls (living walls) are constructed with the appropriate growing medium contained in matting or blocks fixed directly to the building façade. Provision for watering and maintenance is necessary and the whole system requires refurbishment at regular intervals. Green walls derived from climbing plants supported on stainless steel rods, ropes and mesh are more easily …
Runway distance remaining signs are placed on the side of a runway and provide the pilot with information on how much runway is left during takeoff or landing operations. These signs are placed at 1000 ft intervals along the runway is a descending sequential order. Normally, these signs consist of white numerals on a black …
At some airports it is desirable or necessary to “displace” the runway threshold on a permanent basis. A displaced threshold is one which has been moved a certain distance from the end of the runway. Most often this is necessary to clear obstructions in the flight path on landing. The displacement reduces the length of …