Holdfast Training Services Trial Blog

Period Covered 23 April – 4 May 12

Summary:   Engineer…?

My responsibilities have grown considerably over the last 2 weeks as my role has shifted away from supervising to being a project engineer.  This has happened rapidly and  I have to balance my on site work with office based work.  Efficient time management and communication has been essential as I have also been away from site for 4 days (AER writing, ANZAC Day and 2 days on a Safety Course.)

Also during this period the weather has shifted and the rains have begun.  This has caused considerable disruption and as foreseen in my last blog it will be the simple/stupid errors that threaten the job and not the complicated technical aspects.

During this period I have completed the following:

• Supervision of GMF ground work contractors – bulk & detailed excavation and pile cropping
• Technical Anaylsis and plan for project dewatering, including brief to client.  (Support from John M really appreciated)
• Dewatering Tender Analysis and award of $700,000 of dewatering work. (13 deep excavations and 180 pile caps)
• Dewatering Activity Method Statement written
• Given responsibility for approx. $3 million of Post Tensioning work.  I will be responsible from writing the scope and schedule of work through the whole of the tender process to implementation on site.
• Completed TRA and Hazard Inspection audit
• Attended 2 day Safety Risk Leadership Course
• Safety Supervision
• Programme co-ordination meetings

Work on site.  Exciting times on site as the Northern end of the service tunnel has begun to look like a tunnel with the blockwork wall being constructed and the formwork for the roof slab in place ready for a pour this week.   Work on the remaining sections of the tunnel continues but the arrival of the rain has caused disruption (lost time, unable to waterproof in the wet and the problems with Syphon A, see below).

The remainder of the site continues its steady progression with the site opening up as the bulk excavations continue and piling the final portions of the retaining system has begun.

Finally, worthy of note is that work to divert a high pressure gas main in the North East Corner of site is due to occur on Monday.  Once complete this will enable the completion of the logistics sliplane and provide a drive in/drive out solution to material deliveries.  This work has been delayed for 3 months whilst the Client and Power company come to an agreement!!

Progress Slide

Issues/observations.  Water Water Everywhere:

With torrential rain arriving in Perth it has caused considerable problems for the Southern End of the Service tunnel.

The first bout of rain arrived overnight last Saturday and resulted in the collapse of an excavation.  This was dramatic enough but was made worse as it covered the final portion of the service tunnel that had not had its slab poured.  The collapse caused a 10m x 10m area containing the already the set out reinforcement ready for a pour on the Monday to be covered in sand.  This took 3 days to clear as the reinforcement was stripped back and various “honeysuckers” were employed to clear the sand away from the mesh.

This meant by Thursday parity was reached.  Just in time for another morning of torrential rain on Friday.  What was first suspected as just bad luck (no one was on site to see the first collapse), turned out to actually be a simple mistake by the project.

In order to connect the hospital to the storm water system (run South to North) a serious of symphonic drains (connected chambers) are required to store water and divert it under the major energy services will run ( they run East to West).  The syphons had not been fully constructed (not an issue in the dry) and the project had forgotten/not thought about capping the inflow from the rest of the surrounding area’s stormwater system.

As a result a “water flume” began pouring out of the unconnected syphon and flooding Area A again!!!  After much wading around and “playing” with small grindex type pumps we lost the battle!  A more permanent solution has been devised we plan to construct a sump where the stormwater enter site and a gilkes pump to pump water from the sump past the offending unbuilt symphonic drainage system and into the existing stormwater system.

Storyboard to Show Area A Problem

Further Work

• Continue with dewatering plan.  Liaison with contractor, co-ordination with contract administrators and sub contractor to ensure delivery on site.
• Post tensioning work.  Write tender plan and schedules in order to brief management on Wednesday and begin the tender bid process.
• Prepare for CI’s Visit.