Chandramohan Hangekar, Chief Engineer (Retd.), Water Resources Department, Government of Maharashtra, Pune, and Vice President, Ferrocement Society, India
Maharashtra recently faced the drought situation in many districts. The groundwater level is reducing every year. Small dams or small natural nallas can recharge the groundwater, thereby elevating the water table. Such crash program is being implemented by Government of Maharashtra and the success is visible now. Ferrocement small dams are eco-friendly, and acceptable because of use of local material and labour. Different designs are discussed here.
IntroductionFerrocement uses less cement and the thickness is also very small as, such intelligent use of this material is possible in water retaining structures. In Mexico, ferrocement dams with curved sections and small wall thickness are built very frequently. Small dam is also built near Pune, India. The technique is appreciated by Government officers as well as by JALBIRADARI. Due to simplicity, these designs can easily be adopted by villagers and NGOs.
Different DesignsFerrocement can be used in small dams in different ways.
2.1 As a core- As ferrocement has a unique property of imperviousness, it can be used as core material surrounded by pervious local and cheap material.
2.2 As encasing material- Ferrocement is very resistant to take tensions and flexure. As such, boxes of ferrocement filled with pervious material can be a good replacement to masonry and mass concrete construction.
2.3 As covering material- The beauty of ferrocement to adopt any shape can be used to cover the loose and KACHCHA BANDHARA. This thin cover acts as a impervious layer and a protection to loose material also.
2.4 Ribbed curved walls-curved ferrocement walls act as arches and the water pressure is taken on convex surface. The downstream surface is strengthened with ribs.
The designs are described below: