Pre pour and post pour concrete inspection

PRE POUR AND POST POUR CONCRETE FOOTING INSPECTION

Step by Step Inspection of Footing | How to Inspect a pre-pour and post pour concrete footing

In this article, we are going to learn how to inspect a footing before concrete pouring
Duties & Responsibilities of a QA QC Inspector | Site Inspector during Concrete footing Inspection.

Footing Inspection

Checklist to inspect a pre-pour concrete and post pour concrete

8 IMPORTANT TIPS FOR PRE-POUR CHECKLIST AND INSPECTION

What are pre-pour and post-pour concrete inspections?

Pre-pour inspection is done prior to concrete inspection, and it includes drawing review inspection, survey report inspection, cleaning, shuttering inspection, reinforcement inspection, concrete cover inspection, binding wire inspection and etc.

A post-pour inspection is done during the concrete pour which includes the fresh concrete testing, cube testing, slump testing, and inspection after concrete-like hard concrete inspection, curing inspection.

DRAWING REVIEW

The drawing shall be IFC/AFC (Issued for Construction/Approved for Drawing) drawing and latest revision. No Super seeded or older revision shall be available on site. It may cause the NCR and rectification work may occur if work is executed by super seeded drawing.

SURVEY REPORT

Survey report shall be available at the site during inspection with proper coordination as per the latest IFC/AFC drawing. The survey report shall be attached with RFI duly signed by the surveyor. The survey report shall mention clear variation if any is found at the site.

CLEANING

Cleaning shall be done. No dust or loose particles shall be available inside the footing area. All reinforcement shall be clean and rust-free.

Footing Inspection

WATERPROOFING

Air bubbles or air shall not be available inside the polythene sheet. Minimum 15cm overlap shall be done on existing polythene. If another type of waterproofing like bitu board, or bitumen paint is mentioned in the drawing shall be applied.

SHUTTERING

1. Shutter shall be clean and clear from dust, shuttering oil shall be applied inside of the shutter.

2. Alignment shall be checked for shuttering, Shuttering alignment shall be straight.

3. Dimension (Height, Width, and Length of Shutter) of shutter shall be checked as per drawing. (Generally, 1cm is allowed shutter dimension) Project specifications shall be checked for allowed variation.

4. IF the height of footing is more than 600mm, plumb shall be checked for vertical formworks. For small footing visual inspection of verticalness is sufficient.

5. Bracing and supports for formwork shall be checked whether is strong enough to take a load of concrete during the concrete pour.

REINFORCEMENT

1. Reinforcement shall be supplied from an approved vendor or approved reinforcement shall be used

2. Reinforcement shall be clean from dust and rust.

3. Reinforcement dia shall be checked as per IFC/AFC drawing. During the inspection, the drawing shall be checked to verify the dia.

4. Overlapping of reinforcement shall be checked as per project specification or available general notes. Generally, 50D is taken for overlapping.

5. During footing reinforcement inspection embedded reinforcement for Columns also shall be checked. Special care shall be taken during column reinforcement inspection. Height shall be checked for column reinforcement.

6. Center to Centre distance shall be checked as per drawing.

7. Development length shall be checked as per project specification.

8. If any damage to the epoxy paint over the reinforcement, touch paint shall be done before 24 hours of the concrete.

Reinforcement Inspection

REINFORCEMENT COVER

The cover shall be as per project specification. Generally, for footing concrete cover 50mm, a Cover is provided. If Footing is in direct contact with water then cover shall be 75mm. The cover shall be checked for the bottom, upper side, and sides. The concrete cover for the column is a minimum of 40mm, and for slab concrete cover shall be 20mm.

BINDING WIRE

After tying excess binding wire shall be cut and removed. Excess binding wire can cause the reinforcement rusting. Binding wire can be alternate or continues it depends upon the project but reinforcement shall not replace during the concrete. The binding wire shall be approved and as per project specification. Epoxy Coated or Black Annealed wire of 16G shall be used as per project specification recommendation.

BINDING WIRE

Inspection during Concrete Pouring

1. Design Mix and supplier shall be approved.

2. When the Concrete truck arrives at the site, the site inspector/ QC Inspector shall review the batch ticket.
a. Vehicle dispatch time shall be reviewed and noted.
b. The concrete mix shall be as per the approved IFC Drawing.
c. Slump shall be reviewed at the time of dispatch.

3. Concrete sample shall be taken in a wheelbarrow.

4. Temperature shall be tested. Generally, Max temperature shall be 32 degrees C, but in some cases or projects, it may be up to 35 degrees C.

5. Slump test shall be done for fresh concrete, if slump value is in the limit as per design mix then only concrete shall be allowed to pour.

6. Max 300mm layer shall be poured, the following layer shall be perpendicular to the bottom layer.

7. Vibrator shall be continuous during concrete pouring.

8. Vibrator needle shall not touch the rebar, it causes bleeding in concrete.

9. Finishing of the surface shall be done as per project specification.

10. After the initial setting time of concrete, concrete shall be covered with a polythene sheet to prevent early hair cracks in concrete.

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