Pouring Concrete Walls In Lifts

Have a helper add or remove concrete in front of the screed as you pull it.

Pouring concrete walls in lifts.

Wall to a maximum of 10 to 12 feet in height during one concrete pour. In actual practice each wall was completed in a single continuous pour in one day. Create contraction joints every 4 6 feet. Allow concrete to cure.

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. How to pour concrete in columns and walls. See below for more information on contraction joints remove forms and install waterproofing and drainage system. Make multiple passes if needed to create a flat evenly filled area.

In commercial construction walls may be higher 14 to 18 feet. The pressure in the icf forms is based on how high the concrete is poured at once. Place concrete at or close to its final position. Pour footings and wall.

If the full hydrostatic pressure assumption was imposed the lift height would be limited to 11 feet requiring more than three separate concrete placements. Place concrete walls with a maximum 60cm layer in one pass to avoid segregation. These walls also have the concrete placement in multiple lifts following the same procedure. Reduce cold joints honeycombing and bugholes by training workers how to place and vibrate concrete in walls.

This is done in multiple lifts of around 4 feet or less. If the wall exceeds four feet in height footings should be poured separately. This placement method is a standard practice in the icf industry. Pouring of concrete in columns and walls if the height of these elements is large then it is recommended to place concrete in layers.

In this project 40 foot concrete walls were poured using formwork rated at 1650 psf. Finish the surface of the wall as desired. 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. By pouring in lifts the first part of the concrete starts to set up slightly slake reducing pressure on the lower forms.

If problems occur however corrective action can minimize their recurrence. If the height of the wall or column form is not considerably long pour concrete from the top of the forms. Pour concrete in layers with a thickness ranging from 30cm to 50cm if the height of the rc column is large. The basic principles of placement and vibration are the same for any placing equipment used.

Drag a straight 2x4 screed board across the top of the concrete forms to level the concrete.