Pouring Concrete Walls In Lifts

If the full hydrostatic pressure assumption was imposed the lift height would be limited to 11 feet requiring more than three separate concrete placements.

Pouring concrete walls in lifts.

If the height of the wall or column form is not considerably long pour concrete from the top of the forms. Have a helper add or remove concrete in front of the screed as you pull it. The pressure in the icf forms is based on how high the concrete is poured at once. Pour concrete in layers with a thickness ranging from 30cm to 50cm if the height of the rc column is large.

If too much concrete is poured in one place at one time the pressure build up could become too much for the icfs to handle. Pouring of concrete in columns and walls if the height of these elements is large then it is recommended to place concrete in layers. Place concrete walls with a maximum 60cm layer in one pass to avoid segregation. The layer thickness ranges from 300mm to 500mm and the time between successive layers should not exceed 30 minutes for normal weather condition and 20 minutes for hot weather condition.

See below for more information on contraction joints remove forms and install waterproofing and drainage system. If problems occur however corrective action can minimize their recurrence. Create contraction joints every 4 6 feet. Allow concrete to cure.

Finish the surface of the wall as desired. How to pour concrete in columns and walls. By pouring in lifts the first part of the concrete starts to set up slightly slake reducing pressure on the lower forms. If the wall exceeds four feet in height footings should be poured separately.

Available from diy stores and ready mix concrete companies these contain soluble emulsions that form a protective film when sprayed directly onto the surface of newly poured concrete slabs or walls. This placement method is a standard practice in the icf industry. Pour and level the concrete. Place concrete at or close to its final position.

Pour footings and wall. The 4 foot lift height is a recommendation as a guideline to. Drag a straight 2x4 screed board across the top of the concrete forms to level the concrete. The basic principles of placement and vibration are the same for any placing equipment used.

In commercial construction walls may be higher 14 to 18 feet. This is done in multiple lifts of around 4 feet or less. These walls also have the concrete placement in multiple lifts following the same procedure. Make multiple passes if needed to create a flat evenly filled area.

In this project 40 foot concrete walls were poured using formwork rated at 1650 psf.