Types of Non Conformance in Construction

“QUALITY IS NOT AN ACT. IT IS A HABIT” – Aristotle

MicrobiteWorld tried to list out the most common “Non Conformance” happening in the most of the construction project around the world irrelevant to type or size of the project.

Non Conformance for Trial Mix Concrete Target Design Mean Strength:

Target minimum mean design strength for 28 days of trial mix concrete is not in compliance to approved project specification.

Non Conformance for Steel Reinforcement Traceability:

Heat number or charge number is not mentioned on the delivered steel tagging. Supplier must attach identification number during the delivery of steel. There is no traceability of delivered steel with Mill test certificate. As per specification Each tag shall show the manufacturer’s test number and batch number, mill certificates with heat number or other designation that will identify the bars with the certificate issued for that batch steel.

Non Conformance for Stockpile Material Traceability:

Stockpile identification board not placed in stable condition and just kept on stockpile. Stockpile board not visible as only a A4 size paper board placed. Site engineer is not familiar with stockpile location. Stockpile mentioned in ITR is not matching with actual stockpile location. Some stockpiles do not have stockpile board identification.

Non Conformance for Not having Approved Shop Drawings:

Site activity is in progress without approved shop drawings, which is a violation of the project specification and the project quality plan.

Non Conformance for Material Suitability Test:

Backfilling material used without submitting the suitability test report.

Non Conformance for Shop Drawing submission prior to design detail submission

Submitted shop drawings are referring to the design drawings which are not submitted for review and approval. The Quality procedure for design not followed and did not perform proper review and verification to ensure that related design drawings have been approved prior to submission of shop drawing.

Non Conformance for Temporary works design calculations and shop drawings submitted without Third Party Check:

Temporary work design calculation & shop drawings submitted without approval/review by independent third-party design consultant. This is non-compliance against the specification as well as approved procedure.

Non Conformance for Unapproved Material Use:

The contractor used material which without material inspection request, without material submittal approval.

• Un approved concrete spacer blocks being used on site.
• It was observed that 40mm steel coupler has been used at site without material inspection request and material submittal submission process. Material sampling and source approval test not performed prior to delivery of material at site.

Non Conformance for Steel sampling frequency not followed:

The contractor is not following the steel sampling as per the frequency specified in the project specification.

Non Conformance for Casting of Concrete without approved design & shop drawings:

Contractor has done the concrete casting without approved design & shop drawings.

Non Conformance for Concrete Mix – Durability Assessment Report:

Concrete casting done by the Contractor before the approval of Concrete Durability Assessment Report (DAR) and before submitting all required test results proving conformance of the concrete trial mix with the durability report recommendation.

Non Conformance for Concrete Quality – Concrete Pouring:

Permanent concrete work executed while ambient temperature in rising condition.

Non Conformance for Concrete Quality – Cube Sampling:

Cube sampling area not prepared on flat and stable surface. At site polythene sheet has been placed on undulated ground surface. Flexible plywood has been placed to check the workability of concrete instead of using tray. Demolded cubes found exposed to the sunny weather (not sheltered, not immersed in water, or covered in hessian cloth) at the site on 3^rd day after casting. Cubes shall be covered with hessian cloth and cure time to time with water until it shall be delivered to an approved independent laboratory for further testing.

Concrete Slump Test

Non Conformance for Frequency of Cement & Aggregate Testing not maintained:

Frequency of Sampling and testing of concrete raw materials in batching plant is not maintained as per the specification.

Non Conformance for Cracks in Concrete Structure:

Cracks found in concrete during the post pour inspection for structural element.

Cracks in Concrete

Non Conformance for honeycomb in Concrete Structures:

Honeycomb found in the concrete during the post pour inspection for structural element.

Concrete Honeycomb

Non Conformance for Poor Concrete Quality :

There is poor Quality of concrete delivered at site. It was observed the excessive overflow/bleeding of on final finish levelling. Possible addition of water manually in concrete truck and concrete mixer pump after checking of concrete slump for easy pumping of concrete.

Non Conformance for Concrete Segregation:

The concrete is dropping from 6 m height without tremie pipe. This raises concern that there will be segregation in the concrete as well as it will impact on shutter. This will deviate the plumb of wall.

Non Conformance for Bulging in Concrete:

It was observed concrete bulging which emphasizing poor support used or Lack of proper support system while casting.

Non Conformance for Absence of concrete temperature monitoring system for Mass Concreting (Pile Cap):

The contractor proceeded to cast mass concrete without installation of temperature monitoring system (Thermocouple) and without submitting method statement for installation of concrete temperature monitoring system.

Non Conformance for Proceeding for pile cap finishes without post pour inspection:

The contractor proceeded for pile cap surface finishes and waterproofing primer application without any post pour inspection.

Non Conformance for Pile Eccentricity measured beyond the Tolerance Limit:

During pile eccentricity survey check, pile concrete and steel centers are found beyond the maximum permitted tolerance and concrete cover is less than requirement as per design drawings and project specification. The contractor to check and verify that the required concrete cover should be achieved at not more than 500mm depth from pile cut-off level.

Non Conformance for Pile head damaged at Cut-off level:

Contractor did not follow the cut-off level marked by the surveyor and the pile heads have been cut for further depth of 150mm from cut-off level and damaged the pile head, which will have structural impact on permanent pile.

Non Conformance for Working Piles Used as Reaction Piles:

Working pile used as reaction pile for the static load test which is violation of speciation “Permanent piles should not be used for jacking during testing. Also, the working piles are not monitored during the load test, if the piles may have moved upward in a way that it will compromise their compression capacity.

Non Conformance for Failure to Extract the Pile Casing:

The Contractor tried to remove the temporary steel casing used for pile work by vibro hammer but failed to extract inspite of several attempt. It’s non conformance as the pile was designed without having permanent casing.

Non Conformance for Mismatching of Length of Rebar above Cut-Off Level (COL):

The length of rebar above the pile Cut-off level is not matching with the required length due to the uplift of the reinforcement cage at the time of concreting and providing the arrestor.

Non Conformance for Pile Setting Out:

Punching of Temporary steel casing for piling has been started after that found error in setting out. Because of that, casing has been extracted and installed again.

Non Conformance for Concrete Tremie Pipe Used in Pile Casting:

The concrete tremie pipe used, was shorter 0.37 meter than bore length and was kept 1 meter above casing level. In result the total height between toe level and the tremie pipe was 1.37 meter which was 1.17 meter more than as mentioned (20 cm) required as per method statement.

The bore hole was full of water, and the concrete was poured from higher level openly in the water, the segregation will happen in concrete, the cement will mix in water and only aggregate will settled down in the toe level, which will affect the efficiency of pile concrete.

Non Conformance for Pile Lifted up During Casting:

The cage of pile found lifted. This was mainly due to the improper arresting of the cages. Steel cage arrestors not fixed to stop upward movement of the steel cage. Method Statement has not been followed.

Non Conformance for Lifting Operations

The contractor started lifting activity at site without having approved lifting procedure or without resubmit the rejected lifting procedure for review and approval.

Non Conformance for Improper Water Stopper at Construction Joint:

Due to poor workmanship, water stopper placed at construction joint found came out from the joint.

Non Conformance for Deviation from Approved Inspection & Test Plan:

• The surface finishing and primer application completed on the pile cap concrete surface without any Post pour inspection. This is clear deviation from the approved ITP for the Pile Cap construction.
• Repairing of wall started without any Post pour inspection. This is clear deviation from the approved ITP for the wall construction.

Non Conformance for Not having Approved Method Statement before Starting Work at Site :

The Contractor started the excavation and duct laying works for the system chambers without an approved Method Statement.

Non Conformance for not raising Inspection & test request:

The Contractor has requested the consultant to carry out an inspection without raising an ITR.

Non Conformance for Material used without Material Inspection:

• Material Inspection of binding wire and concrete repair not yet conducted. However, it was observed that materials are being used at site.
• Steel material used without material inspection, No proper follow up & lack of material management.
• Dowel steel bar material used at site without Engineer source approval and Material inspection.

Non Conformance for Backfilling Activity:

The contractor is doing backfilling work without proper layer, without proper compaction and without doing compaction test as per the project specification requirements.

Quality is never an accident.

It is always the result of intelligent effort

John Ruskin

Please let us know if you have more to be added in above list!!

By: Microbiteworld.Com