VDCC tech to help smoothen ride on Hyderabad roads in monsoon
HYDERABAD: Satisfied with the results Vaccum Dewatered Cement Concrete (VDCC) roads laid on experimental basis in different parts of the city, GHMC has chalked out plans to go for more such roads to avoid frequent damages during monsoon.
The civic body, which laid VDCC roads on experimental basis in the recent past at Lakadi ka Pul, Himayatnagar, Ayyappa Society, Niloufer Hospital road, Red Hills, Allapur Road, Kakatiya Hills, Banjara Hills Road No. 12 and few other places in the city, have yielded good results as no damages to the roads have been reported so far.
“We are taking up VDCC roads on a priority basis ahead of monsoon to prevent waterlogging. A new technology is being used in construction of roads, which would help prevent water stagnation and damage to the roads,” GHMC mayor Bonthu Rammohan said.
What is VDCC?
VDCC is a system that is used for laying high quality concrete floors with superior cost-effectiveness. The key to the use of this method is the dewatering of concrete by vacuum process. The vacuum dewatering process removes surplus water present in the concrete. This is done using vacuum equipment comprising suction mat top cover, filter pads & vacuum pump. The process starts immediately after surface vibration.
Filter pads are placed on the fresh concrete leaving about four inches of fresh concrete exposed on all sides. The top cover is then placed on the filter pads and rolled out till it covers the strips of exposed concrete on all sides. The top cover is then connected to the vacuum pump through a suction hose to get the pump started.
Vacuum is immediately created between the filter pads and the top cover. Atmospheric pressure compresses the concrete and the surplus water is squeezed out. This process lowers the water content in the concrete by 15-25 per cent. The dewatering operation takes approximately two minutes per centimetre thickness. The dewatered concrete is compacted and dried to such an extent that it is possible to walk on it without leaving any footprints.
“The process improves strength, durability of concrete by reducing water-cement ratio immediately after the mix is placed while laying roads,” senior GHMC officials said.
