Inspection of concreting works is an important step to achieve greater strength and durability of the structure. Although it is easy to remember number of checks during inspection of concrete member, a checklist is always required for record of the placement of concrete and quality control measures taken at site.
Stages of Inspection of Concrete Works
Inspection of concrete is done in 3 stages,
- During placement
Type of inspection of concrete depends on type of concrete, i.e. PCC or RCC, type of elements to be casted, such as RCC slab, columns, footing, beams, walls etc. It is both beneficial to contractor as well as engineer to maintain the record of checks, so that they can produce it in case of any discrepancy.
It also allows becomes a proof of quantity of concrete work done by the contractor, so that no discrepancy arises during billing.
The checklist also notes the number of cubes taken for the given work and its id is noted in the checklist, so that when cube test results arrive, it becomes easy to identify the structural elements for the given cube test results.
1. Concrete Pre-Placement Checklist
Table 1: Standard Inspection Checklist for pre-placement of concrete.
|1||Centre line||As per drawing|
|2||Formwork & Staging||As per drawing & in exact plum|
|3||Construction joint location*||As per drawing|
|4||Steel reinforcement diameter / spacing & coating*||As per drawing|
|5||Cover to the reinforcement and overlap*||As per drawing|
|6||Shuttering||Aligned as per drawing and in plumb|
|7||RLs and reference levels||As per drawing|
|8||Embedment part check, i.e. insert plates, nipple etc||As per drawing|
|9||Placement of water stoppers, if any*|
|10||Location of construction joint|
|11||Water tightness of shuttering, if required||No water seepage allowed|
|12||Quality of water||Potable and clean|
|13||Measuring jar for water pouring||As per water content requirement|
|14||Quality of materials||As per specification|
2. Inspection during Placement of Concrete
Table 2: Standard Inspection Checklist during placement of concrete
|1||Water cement ratio||As per specification|
|2||Surface preparation by mortar bedding||Fresh mortar|
|3||Slump testing*||As per requirement|
|4||Adequacy of vibration||40mm and 60mm needle required|
|5||Segregation of aggregates||Not allowed|
|6||Removal of temporary spacers and ties*||To be removed|
|7||Check for shuttering prop displacement / settlement||Not Allowed|
|8||Number of cubes taken for testing with identification No.: ________ Id: __________||3 No’s for RCC > 6m33 No’s for every 5m3|
|9||Continuity of operations||No break in between concreting|
3. Post placement Concrete Inspection Checklist
Table 3: Standard Inspection Checklist for Post placement of concrete.
|1||Observation for honeycombing||Not Allowed|
|2||Line and Level||As per drawing|
|3||Surface finish||As per drawing|
|4||Cracks and air bubbles||Not Allowed|
|5||Method of curing||As specified|
|6||Checked for stripping/Removing of formwork support etc. after specified duration of stripping time.||Yes||No||NA|
|7||Checked for position of embedment||Yes||No||NA|
|8||Repair and finish all surface defects by specification / approved method||Yes||No||NA|
|9||Surface of part of structure is alright and allowed for subsequent activity / backfilling||Yes||No||NA|
|10||Others, if any|
* The above checklist are valid for Reinforced Concrete works only.
- All the empty space has to be filled and remarks if any shall be written in remarks column.
- Date of inspection of pre-concrete, during placement and post-concrete placement shall be noted as these steps may not be performed on the same day.
- Signature by contractor supervisor and engineer is done after each inspection.