Sunday, August 22, 2010

DRILL, BABY, DRILL

It has been a few weeks since I’ve posted anything here but we’ve been finishing up a busy and very productive summer field season in the paleontology operation at Dinosaur. It has been a banner year with a number of very exciting and interesting discoveries. We shall be reporting on some of these at the Society of Vertebrate Paleontology and Geological Society of America meetings this fall. At any rate, here are a few photos from the summer's fieldwork.


My colleague Dr. George Engelmann on the side of a canyon wall examining scorpion trackways in the Early Jurassic Nugget Sandstone.




Yours truly musing over some Brachychirotherium tracks on the underside of an overhang in the Nugget Sandstone.


Since the demolition of the Rotunda, work at the Quarry Visitor has been more mundane and less dramatic, although of no less importance. One of the problems that plagued the old QVC had to do with the foundation and footers for the vertical steel beams that form the skeleton of the building. For some unknown reason, when the building was constructed in 1957 the footers never went deep enough to anchor into hard sandstone. Rather the footers were placed in the bentonitic mudstone, a rock that simply loves water. Once water seeped under the building the bentonite swelled and expanded --- and contracted as it dried out. Thus began the cycle that ultimately doomed the structure.



Part of the fix for the rehabbed QVC involves better anchoring of the steel framework. To that end, pilings are being placed deep enough down to be in hard sandstone layers beneath the building. That required drilling holes down to the right level, sometimes in excess of 60 feet!





Next the holes are lined with steel casing, a threaded steel rod is inserted, and the hole is filled with cement. Ultimately some 40 new pilings will be put in and they will be bolted to the steel infrastructure via the threaded rods. This should strengthen the building and prevent future movement. However, the actual connecting of the pilings to the steel beams will require a few more rather interesting steps which we’ll follow in an upcoming post.

Photos: NPS

No comments:

Post a Comment