Quality Management and Avoiding the Common (and less common) Defects

Dip visible in NW kerb line
Structures settlement and the after effects on kerbs and surfacing can also affect the bridge joints, making this an expensive fix for the contractor if he has not managed to sew up the earthworks package and does not have supporting quality compaction records.

Poor quality in the construction industry is one of the most common issues that results in lost time and additional costs to a contract. Year on year it costs contractors millions of pounds, damages relationships with Clients, places additional pressures on Site Teams attempting to complete a contract or results in further intervention from Designers through lengthy reports. The implication of finding such workmanship issues can be carefully navigated through controls and an understanding of what is required and what is expected from the specification/design prior to putting people to work. As with most things any defects in construction require re-work to correct the problem and the longer defects remain uncorrected, the more rework we are likely to encounter and the more rework there is likely to be involved. Ensuring that the work force and supervision have the right skills and knowledge, right tools and materials and, following completion, the right protection will all help prevent this from happening.

In the next series of posts I have decided to look at specific issues with different activities and to compile a list of checks that can be undertaken by the Engineer or Supervisor, with some examples,  to help check and ensure that we are identifying the major and sometimes minor details that people miss when planning or executing an activity. As suggested earlier defects can be avoided by sufficient planning and adequate monitoring. Allowing enough time for the work to be done properly and in the correct sequence is always particularly important.

The first at avoiding common defects will look at one of  the most common and versatile construction materials used in civil engineering – reinforced concrete. Following on from that I will go through various other trades and activities which include;

  • Formwork
  • Falsework and Temporary Works
  • Pre-concrete Checks
  • Concrete Checks
  • Earthworks Planning, Bulk Cut/Fill Operations and Finishes
  • Drainage Planning, Pipelaying and Chambers
  • Roadworks – Type 1 Sub-base
  • Roadworks – Kerbs and Finishes
  • Surfacing
  • Sheet and Bearing Piles
  • Setting Out Checks
  • Landscaping
  • Safety Fencing
  • Signs
  • Temporary Works
  • Bridge Bearings

Whilst we review the checks that we should look in the coming weeks there are some simple first steps that can be implemented to ensure the right ethos is achieved with the team to achieve good planning, good leadership and a culture that promotes good quality.

  1. Ensure everyone knows and understands the contractual project requirements and specifications from the designer and the client or clients representative. No client wants a bad job.
  2. Always read the label – People should be encouraged to refer to British Standards, European Standards and Trade or Manufacturer literature. Instructions are there for a reason, if you don’t follow them it will not go well.
  3. Learn to recognise what good looks like. If it doesn’t look right, it probably isn’t and don’t be afraid to stop the work if anything looks wrong. Allowing it to continue could cost more money.
  4. Make sure that everyone is qualified, competent and capable for the activity that you are planning to execute. Hiring a bricklayer when you need a joiner will never work. You should never assume specialist trades know what acceptable quality is, just because they come in a van with a logo on it does not mean they know what they are doing.
  5. Don’t assume a manufactured product is correct, always check what you pay for. Quality is still an issue in a factory, even where quality controls are stricter.
  6. Follow the Inspection and Test Plan set out by the Quality Team and Quality Manager, get involved with its production and complete quality inspection records as the work progresses. Quality can be as onerous as you like and sometimes those with the most letters after their name don’t always realise the workload they are enforcing on people.
  7. Ensure everyone understands the activity, the sequence and what is expected and always take photographs of the works as they progress and get sign off from those accountable or executing the work.
vlcsnap-2011-08-31-19h22m38s214
The Hidden Cost – Pipe damage – Early CCTV can avoid the need to excavate drainage well after installation, reducing costs and identifying defects early.

Making sure that we have enough competent supervision for the normal working week is essential before we move to increase working time to either weekend and/or night work as these are times when defects occur most frequently. We should also scrutinise our reliance on our supply chain and their ability to supervise and correct defects in the manor that we require, from painful experience there will always be a percentage that will not return to undertake the work so early intervention is essential.

Effectively its down to you to ensure that you are right first time because if you think quality is expensive…try building it twice.

Record Keeping and Site Diaries

The more I look the more I realise that people are becoming more dependent on technology for recording. This is not a bad thing, photographs that contain exif data can be helpful as they give position, date, time and location. Remembering what happened and where when the Commercial Team are looking to recover costs or the Forensic Planner is trying piece together a timeline from a disaster project is always difficult so a good site diary is always a massive bonus.

Site Diaries must be maintained by the Section Managers, Supervisory and Engineering staff as nominated by Project Management. The Site Diary will constitute a formalised daily record of contractor performance and as such can be submissible.

The following points indicate the type of information that should be included in the Engineers site diary;

  1. Project Name or Project Number.
  2. Discipline and/or Section – eg. Section 5A and Drainage, Roadworks, Structures etc…
  3. Shift start time and finish time plus the type of shift eg. Day, Night etc…
  4. Weather Conditions – This should be broken down in to AM and PM and can be simplified in to a  simple one or two word statement eg. Fog, Sunny, Showers, Snow, Heavy Rain.
  5. Which operation(s) are ongoing or have started in the area under your Engineering supervision and their progress, this should be a brief description and should include the following key items;
    • Location of the activity, eg. GL G-I and 7-8 or CH196+980-20+050 Northbound
    • What the activity is, such as Earthworks Topsoil Strip, Site Clearance, Steel Erection, fixed reinforcement, poured concrete to wall etc…
    • Any rough quantities of materials imported, concrete poured etc…
    • The type of plant undertaking the work and  a short description of what is there, eg. Cat 316 or Terex AC200-1, 40t ADT, Stihl Saw, 4” Pump etc…
    • The number of men and their discipline undertaking the activity, eg. 2nr Joiners, 1nr General Operative etc…
  6. Any unforeseen situation eg. Hard dig experienced by a sub-contractor installing drainage, obstructions that possibly had not been identified in a site investigation, unchartered services etc…
  7. Any occurrence that has delayed an operation which should include;
    • Who or what was delayed
    • Who or what was ‘responsible’ for causing the delay eg. us, sub-contract, general public interface.
    • A description of what occurred to cause the delay, eg. Plant break down, delayed concrete order, road traffic accident closing a carriageway, design query.
    • The duration of the delay and the time that this delay started eg. 13:00-16:00hrs (3hrs).
    • Any mitigation that was undertaken to prevent unproductive time, eg. The drainage was stopped due to level issues and a clash with a culvert and the gang was moved on to completing MH’s. This should include any plant that has remained stood due to the change in plan.
  8. Any verbal discussions with the Client, Sub-contractors, Clients Representative, Third Parties (eg. HA, Building Control, Local Council, HSE, EA etc…). This should include any agreements that were made with the parties involved.
  9. Any instructions that you gave to other members of staff/operative or sub-contractors working for us.
  10. Any instructions that you were given by the Designer, Architect or Clients Representative.
  11. Any variations on, or changes agreed to the specification
  12. A description of any incidents or occurrences which have resulted in;
    • Accidents
    • Dangerous Occurrences
    • Damage to Private Property
    • Damage to the works completed or work in progress
    • Damage to Statutory Authority Services eg. Water, Gas, Telecommunications etc…
  13. Anything else that you think may be relevant. It does not matter if your observation encompasses another section of work, what you see  may be relevant to unnecessary costs incurred by your Business unit or could give further insight in to what is occurring in a section of works.

You should get in to the habit of completing a daily site diary during the course of the day wherever possible, a short time spent writing in to a note book what you may have seen or on to a diary sheet as you leave an area or whilst you chainman is driving through site helps greatly with spreading the workload. This prevents the need for stopping on at the end of the day to write up what has happened or in some instances forgetting what has happened during the course of a day.

A detailed diary gives a good indication of what is happening on site and some of the items listed above may have contractual implications which could require notification to your Line Manager or the Quantity Surveyor responsible for a works package or sub-contractor.

Once complete the Site Diary must be distributed in accordance with the requirements of the Project. A copy must be distributed to the Commercial and Engineering functions as a minimum.