Anchoring Systems
Some
testing applications require that the tooling is pushed into the ground
instead of hammered. To do this, the power of the machine's probe cylinder
is used to advance the rod string instead of energy from the hammer. To
achieve any sort of depth, a suitable reaction force must be used to balance
the pushing capacity of the rig. This means that you either need a really
heavy rig or you need to anchor your machine. For all of you out there
who don't feel like lumbering around the site in a 25-ton truck, Geoprobe
Systems® has a system for anchoring your soil machine. You may not
realize it, but the probe cylinder of your Geoprobe® direct push machine
has quite a bit of power in it to push tools (9 tons of push in a 5400
series machine and 16 tons in a 6600
series machine). In many cases, you can push a tool just as deep as
you can hammer it.
There are some tools that are specifcially designed to be pushed. (i.e. CPT, SCPT, and MIP static push probe), and there are some that can have a dramatically improved lifespan when pushed (i.e. the MIP probe). Some of our customers have even pushed 2.25 in. rod on some really deep holes. This saved a lot of unnecessary wear on the threads.
Geoprobe® Anchoring Systems:
3-Anchor System: Anchors are turned into the ground using the rotary hex drive of the hammer. The anchors hold down a foot anchor bridge, and the probe foot slides underneath the foot anchor brige where it is held during pushing. The anchors, which are screwed into the ground before testing and screwed out after testing, provide a suitable reaction force for pushing with the Geoprobe® direct push machine. The three-anchor system is capable of providing up to 9 tons of reaction force when it is anchored with 4-in. anchors into a suitable soil.
5-Anchor System: Increase the reaction force by adding more anchoors. Add two crossbeams, two anchors, two anchor plates, and two vises and now you have a five anchor ssytem. This set-up can be useful when you are anchoring at a site with loose soil in the first few feet.
7-Anchor System: Add two anchor foot bridge extensions to the 5-anchor system and you can use up to seven anchors to hold your machine down. The extensions slide into the ends of the foot bridge and are pinned into place with quick-release pins. The additional anchors increase the reaction force that the anchoring system can provide.