You will need
  • - line
  • roulette,
  • calculator.
Ready-mixed concrete of various grades, which is a semi-liquid mass, depending on its structure has unequal shrink – the smaller the cement and water, the less significant changes of volumeand of the concrete during curing. In addition, the magnitude of the shrinkage of concrete is influenced by other factors, such as the way of the seal: when shtykovaniem shovel shrinkage is smaller than when sealing concrete with deep vibrator. When calculating the required amount of concrete generally use the same average coefficient of shrinkage equal to 1,015-1,02.
Calculate the volume of the pre-concreted design, according to the draft (sketch). To do this, multiply the width, height and length of the Foundation.
Check after the construction of the formwork according to height, width and length of the Foundation with design values. Small deviations of the dimensions in a big way lead to a substantial increase in the required amount of concrete. Use of inventory formwork of steel frames and plywood allows to minimize these errors.
Multiply the resulting volume by the shrinkage factor.
Subtract from this value the volume of all openings and niches for engineering services (pipes, ducts). To do this, you need to calculate the appropriate volume according to the formula for determining the volume of a cylinder (area of a circle multiply the height) or a parallelepiped (length multiplied by width and height). The resulting value will be the amount of concretethat is required to fill the design.