Street lighting

Street lighting is an important thing to be implemented with utmost care and vision since this affects both motorists and pedestrians. The main reason for accident during night is poor street lighting. The major varieties of street lamps used are tungsten filament lamps, tubular fluorescent lamps, sodium vapour discharge lamps and mercury high pressure discharge lamps. Tungsten filament lamps are suitable for minor residential streets and pedestrian walk-ways. Tubular fluorescent lamps are best for shopping streets. Sodium vapour discharge lamps and mercury vapour discharge lamps are widely used nowadays in the streets of India. These lamps are highly efficient and have longer life span. Different treatments and skilled method has to be employed while designing lighting at bends or curves, bridges and tunnels.

Polymer fiber reinforced concrete

Polymer fiber reinforced concrete or PFRC is a composite material which is used for building construction. This is a relatively new material with more efficiency, strength and is inexpensive. Nowadays it is commonly used for the repair of new and deteriorating structures. PFRC responds linear-elastically to axial stress. The response of PFRC to axial compression is dependent on the relative proportion in volume of fibers, the characteristic properties of fiber and resin and the interface bond strength. The failure of PFRC during compression is called fiber buckling. Tensile strength is a main cause of concern in PFRC and is mainly dependent on the fiber material. PFRC is durable and less corrosive. PFRC can be used in bridges, columns, in the repair of new buildings, in the repair of damaged structures, in siding, in cladding, in roofing, in flooring and in partitions. Slurry infiltrated fibrous concrete (SIFCON) is manufactured by infiltrating cement slurry into a bed of preplaced fibers. SIFCON is a high volume fibrous concrete where fiber content varies from 8% to 20%.  

Float switch

Float switches are used to maintain liquid levels in a tank. Here a pump is used which can be energized when liquid level in the tank falls and can be de-energized when liquid level in the tank rises.  For this, a sort of sensor is also required to sense the preset height. There exist two varieties here- rod type and chain type. In the rod type, a float is attached to the lower end of the rod and the rod passes through a hole of the lever. Two ends of the rod are fitted with fine stoppers which cannot pass through the hole. In the chain type, a chain rolled over a pulley is used. Here a float is kept at one end and a counter weight at the other end.