Marasy Construction: Progress!

Well I have been remiss in not posting this before so I will do it now. 

The site sign (internally illuminated at night.) We are on there! As you may or may not know we have two parcels known as Plot 99 and Plot 101.  These two properties are separated by a development designed by HOK. 

First let’s look at the two parcels next to each other.

 

Plot 99                                     Plot 101

Plot 99 is where we have seven buildings and a small marina facility – it is the main site of the Marasy Development and terminates what will soon be a continuous boardwalk.  The black lines indicate the existing property lines.

On plot 101 we are building in the dry thanks to the TDIC cofferdam*.  The “sharktooth” at the bottom center of the picture is where TDIC are providing a lifting station for their marina which will occupy most of the open waters in the basin.  This is already a two months into the works.  TDIC are ahead of us but you can see our two ton crane lifting a block for placement on our wall.

The rock foundation base has been laid and the blocks are lifted into place.

There was not a lot of progress shown in the photos between when these pictures were taken.  That was about to get worse as the Abu Dhabi Municipality (ADM) shut down work on this site for lack of a building permit.  The strange thing here is we were previously assured that a permit was not needed for marine work which was the case at one point in the past.  Just….not now.

You can see our neighbors have already backfilled the rock wedge behind their wall and the basin remains quite dry.

No progress on our site but you can see things really kicking into gear with our neighbors.  On the right side of the picture you can see our neighbors have installed sheet piling where they are beginning to drill secant piles.  In the basin you can see piles and pontoon platforms for the marina.

Wow….a busy month for everyone else.  We are still struggling with not just our permits but our “affection plan” (a document for which I have very little affection) is being withheld for all kinds of silly reasons.  We are fighting out daily between all kinds of agencies to get the go ahead.

You can see that the marina pontoons are flying into place and the wall of our other neighbor is now flying up.  They cleverly hired the same contractor as TDIC (developer building the marina and wall with the shark tooth) so they already have their groove on.

well that happened fast didn’t it?  yup!  We got our permit and affection plan and BOOM!  DONE!   At this point you can also see that we have demolished most of the existing quay wall as well.  Our third layer is complete and once the demo is done we can place our fourth layer of block and be done.  As soon as the demo is done we can backfill, place the rock wedge with geotextile fabric and walk away.

Almost done now.  Our top layer of blocks have gone in, the white geotextile is wrapping around the rock wedge and backfilling is ongoing.  You might have noticed that the basin looks a little wet?  Well we all raced to an October 4 deadline because TDIC had arranged a big ceremony that was meant to have a royal spectatorship that never happened.  Opening the bridge to Sadiyaat Island was far more important.  Regardless, the dewatering system has been shut off to allow the ground water to infiltrate the basin.  Once the level of water reached the height of their culvert which goes under the road on the left side of the picture, they let water leak through the culvert into the basin.  The whole process took about 10 days.  Now the water on both sides of the cofferdam have been balanced and they will start removing the cofferdam.

So that is building in the dry.  Let’s look at Plot 99 where we did it in the wet!

Before Construction Started on Marasy Parcel 99. The TDIC Cofferdam is in place and the basin is drying out.

Here you can see the barges used by our contractor to both excavate the trenching for the blocks (and the removal of the material) as well as placing the blocks in the water. *Clearly in the middle of the photo is a cofferdam. This was the result of countless meeting between three developers working in parallel in the area. TDIC wanted to build their wall and marina in the dry which benefitted the other two developers. The cofferdam was first built using steel sheet piles starting on the TDIC side of the bay cutting across the neck and landing on the border between our (ICT’s) Plot 99 and Plot 102 belonging to Bloom (design by HOK.) Once the sheet piles were in, an earth dam was built on either side and the water was pumped out, leaving the basin dry.

The Inaugural block before it was placed in the water.

You can see a crawler crane on top of the cofferdam and our works on Plot 99 under way.

Now you can see our block wall in the water just in front of the coffer dam as well as beyond. These two lines form the top of our “new” site as they form the edges to what will soon be filled with earth and “reclaimed” as new land added to the plot. Two buildings will sit on this reclaimed area.

Far in the background you can now also see our wall progressing well along the existing edge to the site near the rainbow. “What is that thing?” you ask? It belongs to Sheikh Hamad bin Hamdan known as the “Rainbow Sheikh.” It is his own private enclave. – Don’t ask (don’t tell?)….I don’t know what the rainbow is all about. The TDIC marina is cruising along in the foreground.

The enclave.

Here is a close-up of the blocks installed in the wet. Each block is numbered and has its place. This area of water will soon be filled with earth and become part of the site (reclamation).

Getting read to load a block. The block is formed with key holes and the crane with keys. They lock together and the block is lifted. So there is often a mispronunciation of Quay wall as Key Wall….Confusing but same thing.

This is a good shot of the blocks in the water with the geotextile fabric attached waiting the rockfill behind it.

Here you can see the rock going in, the fabric laid back over it and backfilled with earth.

Probably the most telling image is the current satellite photo of the site in Google. Here you can clearly see the wet and dry plots. You can see the shape of our Plot 99 site taking shape as the quay wall is clearly a work in progress. Looking at the site you can see the stacks of concrete blocks curing on site and ready to be installed.

The completed site with ours and our neighbors reclamation works complete, the coffer dam removed and the marina ready for boats.

Here is a neat panorama of the Plot 101 wall complete and almost tied into our neighbors wall.

Now……on to the business of making buildings!

Like most buildings in Abu Dhabi, the structure will be supported by concrete piles/caissons. The water table is very high throughout the island so the piles are typically quite deep.

These auger rigs will be drilling more than 1000 piles!

The tops of the caissons are sticking out of the ground and are waiting to be poured with concrete.

The hole is quite deep as the pile heads are actually 5 meters lower than the current finished grade and will be below the basement level which is yet to be excavated.

Once drilled, each caisson is fitted with a rebar cage forming the reinforcement for the concrete pile. In the foreground you can see the steel sheet piling which will create the water cut-off for the basement area during excavation. The steel sheet piles are about 12 meters deep and are driven down to the solid substrate below and cut the sea off from the works but they can’t hold off the sea for very long – they must work in conjunction with a dewatering system which is installed in parallel.

The rebar cages are being made in three separate workshops on site. Each one takes about 1-2 hours.

Here the caisson is filled with concrete.

Each truck that brings concrete to site fills test cube molds with concrete as it enters the site. The cubes are broken later for strength.

The concrete is pumped in and forces the water out the top – it gets pretty messy. (video to come)

The pile heads are cleaned in preparation for waterproofing treatment.

This pile head is fitted with a concrete top in preparation for a dynamic test. (video to come)

Once the piles are filled with concrete and cured, the caisson is removed and the area is prepped for waterproofing. This is the area at the tip of the reclamation area where there is no basement, so the pile caps will be poured at this level.

This is the inner canal of Marasy. The area we are looking at is on the right side of this photo and is completely reclaimed land.

Here are some of the dewatering outlets dumping back into the Gulf waters. Yes they go through a filtration/treatment tank but I didn’t show this to you.

Here are one of the dewatering wells waiting to be hooked up to the system. There are 30+ deep wells along the perimeter of the wall that will be making the excavation works safe.

On the inside of the site away from the quay wall they were meant to have an open cut excavation for the basement. Because the site work area is so small, the contractor has opted for a soldier pile wall to optimize their work area.

They are spaced 80 cm on center!

This is a dewatering line running on top of the quay wall.

We are looking towards the edge of our site where the coffer dam used to hit land. Here you can see the sheet pile wall being driven behind the quay wall as well as a dewatering line on top already working.

This is a close up of the whole situation. The quay wall is on the far left and the sheet pile wall is approximately 8 meters away from the front of the quay wall blocks and only 1 meter away from the rock fill and geotextile filter fabric behind it. The sheet pile will actually be the support for a concrete block wall which will provide the formwork for the concrete basement wall. The waterproofing will be applied to the block wall and the basement wall poured against it.

On Plot 101 we have a live telecommunications utility line that will remain active during construction. The utility corridor will run across the top of our basement.

Today. Sheet piles are done (in the foreground) The dewatering pumps are working hard but not hard enough. The dewatering contractor is having problems (contractual with the GC maybe?) and haven’t gotten enough pumps going.

Additional submersible pumps arrive on site last night – perhaps the issues have been resolved.

This is at the area under building 2 in the reclaimed area – excavation has begun!

Shuttering (formwork) for the pile caps are made with CMU’s and waterproofing installation is beginning.

The pile caps are all cleaned up, the formwork is done….ready.

Fabric going in ahead of the PVC waterproofing membrane

Piles are being cut down as the area is excavated. This also removes the top of the concrete that mixed with mud as the water was displaced.

Tedious work to be sure!

Formwork around the pile head where an epoxy top will be poured.

Chopped down piles.

This is one of the dewatering wells.

This is the water after coming through a separator and about to be pumped back into the Gulf.

That just can’t be right….

Here it is at the other end of the basement on what used to be terra firma. Soldier pile wall in the foreground, sheet pile wall behind the quay wall on the left. That is a dewatering well sticking out in blue and smaller concrete piles around it.

That is where we are now!!