Site Recce and My Last Blog
I was recently involved in submitting a tender for the construction of for a proposed development that had 3 x 30 storey towers and a common 3 level basement in Brisbane.
I was asked to look at where there were likely to be clashes of ground anchors and neighbouring structures. The image above is what I prepared to brief the bosses and contains a section through the development to show what the rock horizon is.
After conducting a desk top study I had to recce the site and determine what the likely foundations were and whether they could impact upon the ground anchors that would temporarily retain the basement. From the desk top study I has a good idea the ground profile but no idea of what the foundations of the neighbouring structures were. As the site was only 30 mins away I decided to take a trip out to visit.
As an interesting aside – the dry cleaners photographed above has been leaching chlorinated solvents into the groundwater that has now contaminated the whole site and meant that we have to vapour proof the entire basement because the of these volatile organic chlorinated compounds (VOCCs) into the groundwater.
We had previously looked at a soldier pile and panel solution to retain the basement in areas of good rock and then a water tight wall. This pile and panel solution would now need a bentonite lining and then vapour proof barrier. Attached is a sketch of the design I compiled along with the sub-contractor and environmental consultant. This is not easy to construct and is going to be very expensive as it needs to cover the whole basement. Given the new information the client has withdrawn the tender and is looking at possibly doing away with the basement altogether.
Scan-to-Me from 10 4 31 1 2017-04-04 074557
The end is very much nigh. The attachment to the Multiplex Queensland Head Office has been more beneficial than I initially believed. I have gained significant technical experience from a first class structural engineer but also a vast amount of contractual experience. I have had the opportunity to lead on geotechnical design and hopefully has provided me with some useful case studies for CPR.
In other news the family enjoyed one last holiday in the sun. It was very much needed after the thesis! Mark – bring on the photos of Namibia!
![IMG_6964[1].JPG](https://pewpetblog.com/wp-content/uploads/2017/04/img_69641.jpg?w=595)
Sam and Izzy (with friends) enjoying Fiji
Holdfast Training Services Trial Blog 
Doug
Did you consider any services in the two roads along the north and east site boundaries?
The services had already been identified and mapped. The council do a really good job of keeping records but there is nothing like the resources for a desktop study that we used on Phase One.
Typically the services do not run that deep and are not an issue for the ground anchors.
Understood about the ‘typical’ depth of services but just worth double checking for any Foul Water sewers.
They could be sufficiently deep to affect your first level of anchors which will probably not be that deep. The sewer mains on BPS site affected the ground anchor design hence my question.
No you are absolutely correct, it could get in the way if there was a major sewer. I would double check but, the contamination problem has put this back to the drawing board.