effect of transit time in RMC and its rectification
INTRODUCTION Chapter-1
There many things which make the production of on-site concrete aggravating. Bags of cement, sand, aggregate and possibly other additives must be delivered to the construction area. A supply of clean water is also necessary, along with a rented concrete mixing hopper. Even after all the dusty and heavy ingredients have been loaded into the hopper, there may occur the problem of erroneous water-cement ratio. One common solution to this messy and time-consuming problem is “READYMIX CONCRETE”.
1.1 Readymix Concrete
Ready-mix concrete (RMC) is a ready-to-use material, with predetermined mixture of cement, sand, aggregates and water. RMC is a type of concrete manufactured in a factory according to a set recipe or as per specifications of the customer, at a centrally located batching plant.
It is delivered to a worksite, often in truck mixers capable of mixing the ingredients of the concrete en route or just before delivery of the batch. The second option available is to mix the concrete at the batching plant and deliver the mixed concrete to the site in an agitator truck, which keeps the mixed concrete in correct form. In the case of the centrally mixed type, the drum carrying the concrete revolves slowly so as to prevent the mixed concrete from "segregation" and prevent its stiffening due to initial set. However, in the case of the truck-mixed concrete, the batched materials (sand, gravel and cement) are carried and water is added just at the time of mixing.
RMC is preferred to on-site concrete mixing because of the precision of the mixture and reduced worksite confusion. It facilitates speedy construction through programmed delivery at site and mechanized operation. It also decreases labour requirement, site supervising cost and project time, resulting in savings. It ensures proper control and economy in use of raw material results in saving of natural resources. It can maintain quality through accurate computerized
There many things which make the production of on-site concrete aggravating. Bags of cement, sand, aggregate and possibly other additives must be delivered to the construction area. A supply of clean water is also necessary, along with a rented concrete mixing hopper. Even after all the dusty and heavy ingredients have been loaded into the hopper, there may occur the problem of erroneous water-cement ratio. One common solution to this messy and time-consuming problem is “READYMIX CONCRETE”.
1.1 Readymix Concrete
Ready-mix concrete (RMC) is a ready-to-use material, with predetermined mixture of cement, sand, aggregates and water. RMC is a type of concrete manufactured in a factory according to a set recipe or as per specifications of the customer, at a centrally located batching plant.
It is delivered to a worksite, often in truck mixers capable of mixing the ingredients of the concrete en route or just before delivery of the batch. The second option available is to mix the concrete at the batching plant and deliver the mixed concrete to the site in an agitator truck, which keeps the mixed concrete in correct form. In the case of the centrally mixed type, the drum carrying the concrete revolves slowly so as to prevent the mixed concrete from "segregation" and prevent its stiffening due to initial set. However, in the case of the truck-mixed concrete, the batched materials (sand, gravel and cement) are carried and water is added just at the time of mixing.
RMC is preferred to on-site concrete mixing because of the precision of the mixture and reduced worksite confusion. It facilitates speedy construction through programmed delivery at site and mechanized operation. It also decreases labour requirement, site supervising cost and project time, resulting in savings. It ensures proper control and economy in use of raw material results in saving of natural resources. It can maintain quality through accurate computerized