Unloading at the "Stone Mountain"

The size of the "stone mountain" on Salisbury Beach increases and deceases depending on many loads of stones are brought in and how fast the cranes and load it onto the scowls.In these photos you see the mountain has gotten taller than excavator. There has been a steady stream of dump trucks coming in.

The excavator moves stone from the area where it is dump close to crane.

The excavator moved its arm out of the way of the dump truck. In this series of photos, the angle I took them from makes it look like the excavator is "assisting" the dump truck in unloading the stone.

 

In this photo you see the stone pile is higher than the excavator

Photo Essay

I started this blog with the intention of just doing photo essays. Then I learned how to use the video on the digital camera. The videos are able to capture the action of the construction site better and are more exciting than the still photos. I have tried to strike a balance between photos and videos. I thought I would go back to photos for this post.

 

With this photo I used the stone blocks on the beach to frame the foreground of the photo.The barges came out on the dark side, one of the headaches of the strong contrasting lighting conditions.

In photography classes one is taught the "rules of thirds." This rule is based upon drawing two vertical lines that divided the frame (left to right) into thirds and two horizontal lines that divide it into thirds top  to bottom. You position the subject of the photo at any of the four points the horizontal and vertical lines cross. In this photo I have violated that rule and placed the boom of the crane in the center. Normally, dividing the photo down the center with the subject ruins the composition. In this the case the two distant cranes, one on either side balances the composition and also gives a sense of visual depth to the image. This photo probably wouldn't have worked as well in color.

 Again, in this photo the anchor post of the barge is dead center but the image works. The other two anchors post on the barge in the background help to balance the composition. The darker foreground and lighter (grayer) barge in background helps as well.

In this photo the excavator arm and crane boom lead the eye into the scene.

I like to capture photos of beachgoers with the construction equipment on the Salisbury jetty to show both co-exist  side by side on the beach.

 I like to experiment with different angles and perspectives. Both of these photos were taken from behind the sand dune and only the top of the  tractor, crane, and dump truck are visible. The dune helps to convey a sense of place - the coastline. Neither photo would win a photo contest but both are effective at documenting the construction site.

Tracked Dump Truck Working on the Groin

The groin is the short spur jetty. Komastu CD110R dump truck was busy bringing stones down to repair it during low tide. The new stones are lighter in color against the older stones which are covered green algae. With this video, I suggest turning on the speakers. The excavator carefully loads three stones onto the truck. The driver of the truck is busy working on paperwork in the cab and doesn't hear the horn beep from the excavator signaling he is loaded. The excavator starts to move some other rocks around the pile and then realizes the truck hasn't moved. He brings the excavator claw eye level with the cab of the truck, shakes the claw and beeps again, finally getting the driver's attention.

Tracked dump returning from groin

Excavator waiting to load the dump truck.

 

Cab of the truck in process of rotating around.

 

Ready to be loaded.

 

The stone dust flies as the excavator releases the stone into the bed of the truck.

Excavator turns to get another stone.

Off to the groin with a load of stone.

Tracked Dumped Truck Moving Stones

The latest addition to the equipment line at the Salisbury jetty construction site is a Komastu CD110R dump truck with tracks. The manufacturer officially calls it a "crawler carrier." It weights about 20 tons and has a 12 ton carrying capacity. It has a low and high gear. Its top speed is 6.2 mph. The body of the dump truck can rotate 360 degrees which comes in handy working on the jetty. No need to bang a U-turn, just rotate the cab!

The video shows the tracked dump truck coming over the stone pile and excavator. The driver gets out and the excavator uses the claw to tip the truck up so the underside can be inspect for some reason. The driver then directs the excavator as to which stones he wants loaded. Watch for the driver's hand signs. Once the truck is loaded, it was driven out onto the jetty. The stones were unloaded by an excavator working on the jetty.

 Video of the tracked dump track

Dump truck with a load of stones drives over the beach towards the jetty.

the beginning section of the jetty has been filled with crushed stone to create level roadway.

 

Excavator awaits the arrival of the stones.

 

The cab of the truck was rotated around the excavator starts grabbing stones.

 

Excavator is in the process of placing a large flat stone block on top of the jetty.

Taking the Crane Barge and the Stone Scowl out to the Jetty

The crane barge and stone scowls are sometimes taken out to the Salisbury jetty separately. They are now bringing one of the cranes out around the tip of the jetty to work on the ocean side of it. Previously, the cranes had been anchored along the Merrimack River side of jetty. You will see the video of the crane barge, there are two different size grabbles sitting on deck. One is red (left) and other is blue (right). I have seen both being used fairly regularly.

While the barge is being moved out, the crane's lift cable is attached to one of the anchor posts. It is standard procedure to keep it attach to the last anchor posted pulled up while docked along the construction staging area. Once the barge is in position on the jetty, the anchor post is lowered. The second part of the video shows two tug boats working together to turn a stone scowl in the river and bring it out to the crane.

Video of crane barge and stone scowl being brought out to the jetty.

 

Stone scowl being loaded with small and medium size stone.

Crane barge positioned off the tip of the north jetty. The three anchor posts are in the down position.

 

A portable metal gangway is lowered into position. It allows the crew to access the jetty.

 

After bring the crane barge out, the white and blue tugboats return for the stone scowl.

Clamshell with a Bite: Its Got Teeth!

The next time I dropped by Salisbury Beach State Reservation to see the progress on the north jetty, I found the toothless clamshell benched and a new clamshell in action. The new clamshell has a deeper bucket and has teeth on both halves of the clamshell. It was working far more effective. It was able to grab a decent load of stone each time.

You will notice in the opening scene of the video, the dump trucks are now driving further out on the the beach with their loads. The stones are now being dumped much closer to where the crane is picking them up.

A video of the clamshell with teeth in operation.

 

A sequence of photos showing the clamshell in action.

Toothless Clamshell - Loading the Small & Medium Size Stones "version 2.0"

The stone buckets shown in the previous two posts simply couldn't keep up with the shear volume of small and medium size stones being brought in by the dump trucks. The crew needed to be able to move an entire scowl full of this stone out to the Salisbury jetty. The crane was equipped with a clamshell bucket for grabbing the stone. It was a great idea in theory but problematic in practice. The clamshell had a hard time grabbing more than one medium size stone at a time or a decent bucket full of the small stones. The problem seem to be with the shallow design of the bucket and the lack of teeth on it. The short term fix to this problem was to have the excavator load the clamshell. The video captures this process. It put the excavator operator's skills to the test. You will see him adjusting the position of the clamshell and also very carefully loading it. It was good short term solution. However, It was time consuming and took the excavator away from its other duties of moving the stones dumped by the trucks onto the pile where the crane could pick them up.

On my next visit to the construction site (about a week later), I found the toothless clamshell  unceremoniously beached on the sand in the construction staging area. The crew had come up with a new solution ... which I will discuss in the next post.

 

Video of the toothless clamshell and in action.

 

"bye-bye" excavator

 

Toothless clamshell managed to grab a single stone

 

Excavator filling the clamshell

 

A sequence of photos showing the clamshell dumping its load into the scowl.

 

This is what happens when you don't load the scowl evenly .. it tilts to one side.

Loading & Unloading the Stone Buckets

I had been wondering for a while how the construction crew unloaded the stone in the buckets onto jetty. I finally got a chance to video the process. Two to three stone buckets are loaded either onto the crane barge or into the stone scowl and brought out to the Salisbury jetty. Four steel cables are attached to the bucket, one at each corner. The bucket is lifted off the barge or scowl and set down on the jetty. The construction workers then remove two of the cables on one end of the bucket, the other two are left attached. The crane lifts up one end of the bucket dumping the stones onto the jetty. The bucket is then swung back to the scowl. The excavator moves into to rearrange the stones.

The video briefly recaps the whole process: It shows a dump truck delivering the small and medium size stones. The crane lifting the bucket from the beach staging area and swinging it over to the scowl. (I never got a chance to see the excavators loading the bucket). Finally the  crane dumping the bucket on the jetty. The process of dumping the stone on the jetty took some time. The video has been edited to show the highlights of the process.

 

Two stone buckets sitting in the scowl waiting to be take out to the jetty.

 

Dump truck delivering stone.