Rocks DON'T Rock!
When I visit a new site I try to look at everything... By spotting latent problems on the first visit helps me prepare the client for anything that might influence the time-line and subsequently the budget.
Nobody likes unforeseen costs and in the construction trade they hide around any corner.
Water-flow is a primary concern so we make sure that there is enough "air-space" to create a platform that drains away from buildings and other structures. Water downpipes don't like to be blocked up so there is another thing to look out for.
No matter how much ProNutro you ate as a child... we cannot see under the ground! (They lied to us!!)
So no matter what I observe on the first visit... what lurks beneath is where variations occur.
And so it was, at a location in Bedfordview in Johannesburg.
We quoted on a parking area for a new office block. The soil type was good, easy access for plant and machines, more than enough "air-space" ... we were ready to engage.
We attached the Ripper attachment to our Bobcat skid-steer, a tool that makes light work of breaking up compacted soil. On the first pull, the bricks and rubble started flying!! the more we ripped into the ground the more rubbish we found. our site must have been the dumping ground for all the surrounding buildings.
Experience taught us (the hard way) to improvise our action plans. This gave us the opportunity to design and build our own skeleton/selector bucket attachment which was ready for use on all our Job-sites since then. Here is the selector bucket hard at work separating the useable rocks(70mm) from the rubble. By doing this we dramatically reduce the amount of rubble that needs to be spoiled and carted from the site and also reduces the imported material required to fill the void. It saves us time and it saves our clients money.
On this particular site we spoiled (carted away) 13 x 6m3 truckloads of rocks. That number would have been 70% more if we did not first separate the usable material.
Wys jou net... "a little innovation goes a long way."