Learning stand by GkG

 Methods of mixing:- Concrete is mixed either by hand mixing or by machine mixing based on the quantity of concrete required. 1. Hand mixing:- Mixing by hand is employed only for specific cases where quality is not of much importance, either because of the important nature of the work or because the quantity of concrete required is less. Hand mixing generally does not produce uniform concrete and hence should not be normally used, unless it is for every small domestic works. 2. Mechanical mixing:- Mechanical mixtures can be divided into two main types batch mixer and continuous mixers. Batch mixes produce concrete batch by batch, one batch at a time. The operation is intermittent. The raw material is loaded at one end and the concrete is discharged at the other end. This constitutes a cycle of operation which is repeated until enough quantity of concrete is produced. Continuous mixers produce concrete at a specified rate. The raw materials are continuously entered at one end and mi...

  Curing:- It is a procedure that is adopted to promote the hardening of concrete under conditions of humidity and temperature which are conducive to the progressive and proper setting of the the constituent cement. Importance of curing:- Following are the the importance of curing of concrete. To maintain moisture content in the mix for complete hydration of concrete. To maintain uniform temperature of the concrete. To preserve the properties of concrete, such as impermeability, durability and strength. To reduce the shrinkage of the concrete. Methods of curing:- Sprinkling of water This is useful method for curing vertical or incline surfaces of concrete. The spring can be done in fine streams throw nozzles fixed to a pipe spaced at set intervals. Slogging is done in the same way accept that the slogging nozzles produce a mist like effect, whereas spraying nozzles shed out fine spray. 2. Wet straw or damp earth :- In this method the damp Earth aur sand in layers of 50 mm height ar...