Holdfast Training Services Trial Blog

Here are a selection of some of the issues that have arisen over the last week,

1 – My spanner doesn’t fit – The standard ‘you must be able to construct what you design’ comes to the forefront with my first point. The fabricators constructed the middle waling for the cofferdam, which consists of double UB’s welded together with plates. The problem is that the ends are bolted together and someone decided it was a great idea to position bolts inside of the facing web openings (see photo below).

Solution – Ignore the bolts and weld instead.

Cofferdam middle waling

Close-up of restricted bolts

2 – Answers on a postcard please – Our sheet and CHS piling gang have done a good job, however, they are really starting to drag their heels. The commercial team who draw up the contracts have dropped a clanger and employed them on an hourly rate, which has been fine up until the last couple of weeks. They are now well aware of the last safe moment for the cofferdam to be finished and are doing everything possible to ensure they don’t finish a minute sooner. The question now is how do you speed up someone who has the upper hand and technically isn’t doing anything wrong, frankly neither the carrot nor the stick will work this time!

Solution – …?

3 – The chalk turned to toothpaste – The majority of the fill being brought to site is chalk. This is causing no end of issue given the current weather. If it’s in a dry-ish state and well compacted it forms a sound and stable base for the abutments and road surface to be built on, however, it is not so dry at the moment and yet we are continuing to receive 600 tonnes a day. The lads were told to stockpile it so that it could be distributed at a later date in the 200mm layers with 4 passes from a 3.75 tonne vibrating roller as per MCHW. BUT…what they actually did was cover the whole site with over 1000T and after a night of rain they rolled it. Watching the roller move would be like watching Jabba The Hut on a water bed!

Solution – A nuclear density and plate bearing pressure test will take place tomorrow to assess the situation. Any areas           that require remedial work will be stripped back and sorted. The danger is that if the logistics are not managed correctly then areas could get missed and become soft spots. To add to the issue chalk continues to be imported to site and stockpiled correctly.

4 – My window won’t stay open – In order to monitor the settlement of the site, steel plates have been placed in the ground with vertical dywidag bars fixed to them. As the ground settles, the plates move down and this can then be recorded through surveying. The problem is what do you do when the window of your roller keeps sliding shut? Well, if you work here then you use a gas axe to cut 90-100mm of dywidag off that annoying rod that sticks out of the ground that you have to drive round, so you can make a window wedge!

Solution – Use average settlement data from the other 17 rods on the site to predict the settlement at that point and then offset all future results. Add a note on the site induction that all bars are not to be tampered with and brief all current staff at the following morning brief.

Another settlement rod who had a near miss with the same roller, good job it was protected.

5 – Who ordered the piles? – The first batch of cofferdam piles arrived this morning (AZ 20) but unfortunately the clutches had not been crimped. Before the batch was accepted the order was checked and it turns out it was our fault. The cost involved in sending them back to be altered was not the issue, in this instance it was time.

Solution – Level three precast concrete slabs left over from a design alteration on the crane jetty to create a welding bed. Tomorrow the center clutches will be welded together.

If only the piles had used crimpers instead of straighteners on their centre parting!

Our make shift welding yard

And finally – I saw our crane driver carrying what looked like a bottle of water, he must think I was born yesterday….my money is on gin or vodka!