Civil Engineering

1. Safety Any Structure must be safe with appropriate factor of safety for loading that may come on it during its intended life. 2. Serviceability A structure should provide the service fro which it was constructed upto its whole life under service load. 3.Durability A structure should sustain loading for which it was designed and should also provide performance with safety and serviceability. Durability without serviceability and less margin of Factor of safety has no meaning. 4. Economy Design and construction of any structure should be economical without effecting safety, serviceability and durability. 5. Aesthetic Now a days aesthetic is also the criteria that effects design of structure.

Degree of Workability and their Values as per IS 456:2000 Degree of Workability Where Used Tests Slump(mm) Compacting Factor Vee Bee Test(seconds) Very Low In Road work and compacted with road rollers * 0.75-0.8 10 to 20 Low Light Reinforced section & Mass Concreting 25-75 0.8-0.85 5 to 10 Medium Hevaily Reinforced Section and Pumpable Concrete 50-100 0.85-0.92 2 to 5 High Piling Works 100-150 >0.92 *** Very High Trime Pipe ** >0.92 *** * Its very low workable to test slump as slump will not collapse means slump will be zero * Its  so workable to test slump as slump will collapse instantly *** Test can not be done as instantly concrete surface will be in plane with glass disk

PRIME COAT : A prime coat is mainly responsible for protecting the substrate of a construction project before additional layers are added. In asphalt preparation, they can also act as a binder with secondary and tertiary compounds, creating a better adhesion between the layers. Prime coat asphalt acts as an initial sealer in the asphalt laying process to block the other layers from moisture, dust and debris before additional coating installations. Important things to remember about installing a prime coat or prime coat asphalt are: It provides temporary waterproofing, but must have additional compound layers in order for the floor, wall, or ceiling coating to perform long-term waterproofing duties. The asphalt prime coat must completely penetrate the base surface in order to be effective. A prime coat must completely cure before an additional layer is incorporated. It is vital to be aware of weather conditions when apply an asphalt prime coat. In the case of wet weather, thi...

Today the main use of bitumen is in the road making industry for construction and maintenance. bitumen emulsions are a dispersion of bitumen in an aqueous continuous phase, stabilized by the addition of an emulsifier. They are prepared as emulsions at high temperatures, but applied as solid dispersions at ambient temperatures. In road making, bitumen products are typically applied with mineral aggregate. The strong adhesion that occurs between the bitumen and mineral aggregate enables the bitumen to act as a binder, with the mineral aggregate providing mechanical strength for the road. Bitumen is difficult to work with, at ambient temperatures since it is a highly viscous material under these conditions. it can, however be transformed into a workable state by blending with petroleum solvents or by emulsification with a surfactant in water to form a bitumen emulsion. Emulsified bitumen acts as a key tool in road maintenance and construction technology as it combines amazing versatil...