The average gestation period for rabbits is 31 days; however, it can vary from 29 to 35 days. Does should be pregnancy-checked 14 days after mating. If not pregnant, they can be re-bred immediately.
Buttresses and an arch of the Roselend Dam in France. A buttress dam or hollow dam is a dam with a solid, water-tight upstream side that is supported at intervals on the downstream side by a series of buttresses or supports.The dam wall may be straight or curved. Most buttress dams are made of reinforced concrete and are heavy, pushing the dam into the ground.ater pushes against the dam, but the buttresses are inflexible and prevent the dam from falling over. Buttress or hollow gravity dams were originally built to retain water for irrigation or mining in areas of scarce or expensive resources but cheap labour.
a dam in which the water pressure of the headrace, which is absorbed by the pressure floor (in the form of plates or vaults), is transmitted to buttresses and the foundation.Buttress dams are constructed primarily from concrete and reinforced concrete.oth fixed and spillway buttress dams are built. In comparison with massive gravity dams, buttress dams (especially the multiple-arch type) produce savings of 40 percent and more in concrete and costs, depending on the design and local conditions. The height of buttress dams sometimes exceeds 100 m.