Down in the Pit: While the Rat Mat is Poured

In the afternoon of the day before the big pour, Ed (left), Santos (center), and Fedel meet on the pad to make sure all the survey markers are
in place and there are no last minute changes.

Today is the day the four-inch Rat Mat (Slab) is scheduled to be poured. Barring the forecasted rain, the schedule calls for just the western one-third to be poured. The crew began early this morning (December 15, 2016), to get a jump on the weather. Much needed rain is forecast to come in later this evening. One of the workers was telling me yesterday: “In Southern California when there is a 20 percent chance of rain, it rains. When there is an 80 percent chance of rain forecast, it won’t rain.” Go figure . . . statistics. From grade at the east shoring wall, I could see a beehive of activity in the southeast corner. Although the big pour was the main attraction down in the pit, other activity continued. In the center of the of the pit Vance, the skip loader operator, lightly moved the blade levers as he made final grade adjustments to the bottom of the elevator pit. To the right of the cement truck, a small committee meets to discuss, no doubt, a weighty matter having to do with the construction project. Lower left, the crew continues to work on tier 3 (T-3), in hopes of having the shotcrete blown on T-3 sometime around noon, today.

The size of the pumping equipment is illustrated in this photograph taken at grade level overlooking the pad from the western shoring wall.
For this job a heavy duty 14-wheel Vocational truck with a truck mounted Schwing Long Boom, which is managed by an operator using a remote
control box. By maneuvering a joystick on a small wireless radio control box, the operator is able to control the boom placement,
and rate of delivery several yards away from the concrete pump.

The Masters

of

Concrete Distribution

Above: Rudy, the master of the cement placement. He controls the nozzle with the deftness of cake decorator.

Right: Jose, is the master of the wireless remote box. He handles the joystick with the skill of a 747 pilot.

Rudy and Jose work in tandem. Jose must keep one eye on Rudy and the other eye on the boom while operating the joystick and all the other buttons. Rudy must keep one eye on placement location and the other eye on his concrete crew. All of this is done while keeping an eye out for each other.  How is that for hand-eye coordination?

This process is well choreographed. Each of the crew knows what to do and when to do it.

By noon, the concrete crew had finished the first half of the days’ scheduled pour. Because of the impending rain, it was determined to pour the central elevator pit on Thursday rather than risk it being flooded during the rain storm. The crew had been notified that the scheduled concrete
pour on Friday had been canceled.

With the central elevator pit completed, the concrete crew has moved on to the sump pit, which is located in the northwestern popout. This pit must be completed before the rain because it too would be time-consuming to reclaim it after the rain.

On Thursday evening, the rains did come, and there were prayers that the pad would not flood. From the Medical Center roof camera, it appeared that the construction pad held its own. If Saturday and Sunday are rain free, the pad may have dried out enough to continue the pour on
Monday or Tuesday at the latest. After a visual on Monday morning, the general superintendent will be able to have a better read on
the site conditions.

02.01.17 – X

A view of the east, southeast section of the construction site from the top of the parking structure known as PP4, which is under construction. The

long articulating hydraulic arm of a concrete pumping station is delivering concrete to another section of the rat slab. When completed,

the only section left to complete will be the area where the dirt ramp is located. Also in the picture, steel rebar is being offloaded by crane to the

pit below. A large crane with a white boom just rolled in to offload a mockup of an isolator base. A front loader is compacting a berm to a bench,

where several storage pods will be stationed. At the bench above, a skip loader levels gravel that was just delivered as a steam roller compacts

the gravel. The process will continue on the bench below. On the service road below the “WE ARE SAFETY” sign, the plumbers are moving

large pipes to an area where

03.15.17 – X

This short video clip shows how far the excavator must reach as the last remnants of dirt is loaded into the bucket. After the final grade of this northeast section of the pit,

the last section of the rat slab will be poured.

03.17.17 – X

This small northeast section of the pit is the last area remaining in the pit where the four-inch rat slab is to be poured.

03.17.17 – X

Another view of the northeast corner of the pit. The heavy equipment (left) must stay idle on the dirt until the rat slab around the dirt pad has cured.

03.17.17 – X

This photo was taken standing on the most recently poured rat slab. The last remaining section is at the left out of view.

03.19.17 – X

The heavy equipment has been parked on the most recent cured section of the rat slab in preparation for the final rat slab pour in the northeast corner.

03.20.17 – X

The pumping truck has arrived and is being prepared to begin pouring the small section of the rat slab. The rodbusters (in the circle) are limbering

up before heading out for a day on the rebar.

03.20.17 – X

The last section of rat slab. The small dirt section, center left, will be encased in concrete when the slump vault is poured.

03.20.17 – X

A view of the early morning final rat slab pour. Now that there is no more grading to be done, the crane in the foreground is preparing to lift the

heavy earth moving equipment up and over the east shoring wall.

03.20.17 – X Video

A delightful short clip showing how a backhoe loader is lifted by crane up and over the east shoring wall.