Concrete Testing

This week Brenda once again had to journey to Massachusetts to witness some heavyweight concrete testing. The testing is for the counterweight for a bascule bridge that her company is building in Fall River. Here is the state of the job so far:


The approaches are almost complete, and the steel for the bascule portion of the bridge (the part in the middle that opens and closes) is scheduled to arrive next week.
The test was held at the jobsite, and the concrete supplier had to set up a large hopper for adding the heavyweight rock. They backed a mixer truck under the hopper and started dumping rock into it.

Instead of a crane, an excavator was used to pick up the bags of rock and hold them over the hopper. It worked pretty well.

Just like last time, the guy up on the catwalk had to cut open the bags using a knife on a stick. You would think that the supplier would have come up with a better way to open bags than this! They are scheming up a steel bar across the top of the hopper with a sharp edge to break the bags over, which would eliminate the guy up top. Good idea!

There was a lot of interest in this test. Everyone wants to know what the unit weight of the concrete will be, since it will be very costly to build the bridge if the unit weight is too low.

When the mixing was complete the concrete was dumped out and tested.

The result: The concrete is still too light, by several pounds per cubic foot. The photo below is of the job's general superintendent calling in the results. He was not too happy, but here he is hiding it well.

Brenda will be spending more and more time down at the jobsite as the steel gets delivered...stay tuned for more updates as this bridge gets built.