Wednesday, July 27, 2011

Aqdeh #1


The big day finally arrived, and we completed our first roof / slab pour (or Aqdeh) without any glitches. The excitement was palpable at the site, and by the time the concrete arrived around 1pm we were all anxious to begin. Below are the photos from the days' activities, which culminated in a (well-deserved) traditional Mansaf meal with the crew:



(concrete pump truck arrives and begins the pour)
(crew member directing the B300 strength concrete along the main beams first)
(electric wire conduits for future electric lines are poured into the slab)
(the stairs are poured)
(crew vibrating the concrete into the beams and ribs, while foreman discusses next area with pump operator)
(another one for the "Not-OSHA" files: banging on the mixer from the inside with a hammer ... while it's spinning)
(almost done with this quadrant, with extra concrete being handed down to the worker on the stairs)
(foreman directing traffic)
(starting to smooth-out the concrete on completed areas)
(finishing out completed areas)
(finishing out completed areas)
(more than half-way through)
pouring concrete onto the inverted beam)
(the crew posing after seeing me with a camera)
(finished product)
The pour took around 4 hours, although it should have been completed in 2.5 hours. The main delay was caused by delays in the concrete mixers arriving, and apparently concrete schedules are notorious for these sorts of slides.

We poured 79 cubic meters, the slab was 32 centimeters thick over an approximate area of 380 square meters. Now we need to spray the slab with water twice a day for three days, and leave the support jacks in place for 10-14 days (depending on the temperature and humidity) and we've got ourselves a roof slab.

Next up, starting work on the columns and load-bearing walls: forms, steel and concrete all over again in order to prepare for the more-extensive stone-work that will be part of this next (and all future) floor(s). We also have the insulation to complete under the future gardens and more fill to import after we build the retaining walls along the sides of the property.


Saturday, July 23, 2011

Getting Ready for 3Aqdeh

The final preparations for the 3Aqdeh are under way. We've completed our first phase of insulation and fill import around the basement floor, set up the Hollow Concrete Blocks (HCB) on top of the roof / floor forms, and distributed the steel reinforcement bars along the beams, tie beams and ribs to reinforce the slab. 

We've also completed coordination with the electrical contractor and the plumbing contractor to set up the necessary sleeves that will allow them to pull their wires / pipes through the slab after the 3Aqdeh pour.

Below you can see photos of the fill being imported and distributed. We placed the fill on both sides of the retaining wall in order to maintain the neutral loading it was designed for, and filled only about 1 meter behind the second basement wall in order to establish a ground elevation suitable for setting up the insulation layer. This layer is composed of a 2-cm thick styrofoam board that is protected by a wall of thin (10-cm) concrete blocks, which required the fill underneath to act as a foundation for the insulation wall:

(truck importing fill material)
(fill being imported by the truck on one side and distributed by the bulldozer on the other)
(fill delivered at the top of the future street to be pushed behind the wall) 
(bulldozer spreading the fill material)

Additionally, we ordered around 1,800 Hollow Concrete Blocks (HCB) that will make up the majority of the floor slab, and the crew distributed the blocks in accordance to the structural engineering plans. The blocks sit directly on top of the wood forms, and they are separated in order to place reinforcing steel beams and ribs between them to support the slab structure after the concrete is poured and the forms are removed. Progress pictures, as well as some detail work below: 

(HCB delivered)
(HCB distributions in progress)
(three-quarters of the roof area completed)
(final blocks in place, ready for steel)
(beam reinforcement between HCB's, as well as inverted beam forms shown)
(the inverted beam forms were tricky because they need to "float" to allow concrete underneath)
(sunken slab area doesn't have HCB, to allow for pipes to be set up under future bathrooms)
(beams and tie beams need to have all the steel tied together by hand, one bar at a time)

(final preparations for the concrete pour)

Finally, I wanted to post some photos showing the form and reinforced steel construction details for the staircase because it's always been difficult for me to picture how it's done. I now have a chance to see it as a work in progress and it's helped me understand what goes on. Please feel free to post a comment if you have any questions about the photos below and I'll be happy to elaborate on them:

(forms are built like a slide, then reinforcing steel in set in place.
Notice the faint outline of the stairs drawn in red marker on the wall to the left)
(after steel is complete, horizontal forms are added that allow concrete to flow underneath them)
(detail of the stair forms. All forms are fixed to the wall as well as to each other)
(steel from the top of the stoop reinforcement goes to the bottom of the stairs and vice-versa)
(reinforcement bars protruding to set up for the next level of stairs)
Next up, our first 3Aqdeh or roof/slab concrete pour that will complete the 3Adem (bones) phase of the second basement floor.






Friday, July 8, 2011

Second Basement Progress

The past couple of weeks have been exciting at the project site. Work has progressed fluidly, improvements are visible fairly quickly and we've started on our first stone wall. The reinforced concrete  walls and columns for this floor were formed and poured in three phases, in order to keep the amount of lumber tied up in forms to a minimum, as well as to distribute the work among the crew efficiently from an operational management standpoint (completing the pour opens up work for the more junior workers, in the form of cutting the 6mm tie bars, taking the boards down off the walls and columns, and cleaning the forms of all the nails used to hold them together).

With the exterior walls completed, one can begin to see the space that will become the building storage units and the small 120-square meter (~1,200 square foot) apartment that is on the eastern side of this floor. As soon as the third and final phase of pouring the walls and columns was completed, the crew began putting up the forms for the roof slab, called 'Aqdeh. This is a major milestone in the construction of every floor, and it is customary for the contractor or the owner provide a traditional meal to the crew called Mansaf particularly for the first 'Aqdeh of any project.

Below you can see photos of the exterior walls and columns after the first phase of pouring, as well as what the building looks like today, with all the exterior walls completed and the forms for the 'Aqdeh beginning to cover the floor surface.


(northern wall along the future street)
(exterior walls completed, including stone facade on eastern elevation)
('Aqdeh forms going up. Steel, hollow concrete blocks, then concrete will follow)
(second basement floor taking shape)
('Aqdeh forms are placed up on jacks and reinforced in both directions)

One of the most amazing things for me during this stage has been the realization that this building is going to be built one stone block at a time by two stone builders (and their assistants), and that all the other buildings around us in the part of the world were built the same way. The stone builder places mortar around each stone, levels it, cuts the stones to fit the available openings, then builds forms behind the stone wall and places buckets of concrete behind the stone to complete the process (a bucket is used instead of the concrete pump to ensure the stability of the wall and to make sure the carefully placed stones don't move after initial placement). 

The other exciting thing about the stone work is that it brings with it a new avenue for learning, as it has its own construction methods, timing, materials ordering methods, and language (there are different names for the flat stone pieces, the corner pieces, the side-frames for windows and doors, the top or bottom frames for windows and doors ... and so on). Below are photos of the stone wall construction from various vantage points. 

(stone builder placing a window side-frame piece)
(view of the same from the other side. builder on the left, assistant on the right filling in mortar along the stone edges)
(assistant cutting the stones to fit available spaces)
(the forms behind the stone face, where concrete will be poured in by hand using buckets)

As we close in on the completion of the first floor, our costs are becoming better defined which will allow up to finalize our pricing and begin our marketing efforts in ernest. That is something else that I am looking forward to, since all I have to gauge market saturation up until now is anecdotal evidence and it would be nice to generate heavy interest to validate our assumptions when the word gets out about our project. I am confident that we have a distinct product given the level of detail that has gone into the design and that is going into the construction and finish-out, and of course it helps that the project location is considered one of the best areas of town.

Saturday, June 18, 2011

Slab

After many weeks of work on the foundation, we finally poured the slab and the building has taken shape. It's a substantial milestone, and it was fun to watch everyone's energy pick up to try and get ready for the pour including the plumbing and electrical subcontractors.

Below you'll see photos of the crew preparing the forms for the final Ground Beams, placing the reinforcing steel, and spreading the remaining fill evenly over the rectangular pads remaining in between the Ground Beams. After that, they spread plastic sheets over the fill as a moisture barrier, then placed a steel grid (8 mm thickness, in 20-centimeter square grid openings) over the plastic as reinforcement for the concrete slab.

You'll also see the plumbing sub placing his wastewater pipes that have to go under the slab in place, and the electrical sub placing his high and low-voltage conduits and sleeves under the fill material to establish his routes under the slab.

(crew and subcontractors working)

(plumber setting up the WW drain for a future toilet)
(plastic sheets being placed over the smooth fill and WW pipes)

(final pads remaining are being worked on by the electrical sub)

(at the end of the day, awaiting the concrete pump truck next morning)
The pour went smoothly, and included approximately 50 cubic meters of concrete for the Ground Beam and slab (the 10-centimeter-thick slab took around 35 cubic meters while the Ground Beams took up another 15 or so cubic meters). We also poured the third phase of the reinforced concrete retaining wall along the front (north) boundary, completing the first 3-meter-high run along the entire 30-meter stretch of street frontage. The retaining wall took another 13 cubic meters to complete, bringing the total for the wall so far to around 90 cubic meters.

Th crew used hand shovels to spread the last of the concrete evenly over the slab, and a make-shift level spreader to smooth the surface (as seen in the first two photos below):

(using the level-spreader to smooth the concrete)
(using shovels to spread the concrete evenly)
(close-up of the finished product)
(the building takes shape)
(retaining wall shown in foreground)
(the view from the street)
Next phase will bring forming of the walls for the second basement level, ordering reinforcement steel and the new (for me) process of placing an order for the stone facade and overseeing that aspect of the construction work.