Slab Progress - Part 2

As promised earlier this week. I witnessed the slab pour on Monday and took some video so my family could see some action of the event. Here it is;

Thankfully, the slab has been left to cure for the rest of the week. Some areas are now showing drier patches as the slab cures and dehydrates.

Windows also got delivered this week. There are alot of expensive windows lying out the front now. Hopefully the thieves don't help themselves as i certainly don't want any delays by things going missing!

There is a missing edge on the front corner of the garage. The front brickwork should overhang slightly to conceal the downpipe

Kitchen, Family, and Dining room area

Kitchen island plumbing stack

I am a bit baffled by this corner. It is rather damaged as the concretors lifted the stryrofoam early by the looks of it. It's also strangely located on the front edge. I'm not sure how the damaged face of the slab edge with some inlaid brickwork will improve this, and the front face stops abruptly.

The ugly corner

Slab Progress

What an exciting day yesterday! 

I arrived onsite to view the slab pour at 7am and found a hive of activity. The Pump contractors had already run the hoses and put some tyres over the formwork to restrict the hose movement. The concretors were tweaking the formwork following Rick's advice over the weekend, and Mark our Site Supervisor was inspecting the remediation areas advised by Rick.

7am - The troops are ready for action

The first 7m3 truck arrives at 7:15am and causes a little stir on the street. They begin pumping and decide 10 minutes later to move the truck fully onto the council strip due to blockages on the road.

The first of many trucks to feed the pump

The crew begin from the alfresco emptying two trucks in that area alone. The drop edge beams consume the majority of the concrete.

Two trucks down and only 10% there

8:15am - The third truck arrives and gets through the majority of the lounge, dining, kitchen, and tank/ACU pads.

8:30am - 50% complete

9:45 - The fourth truck in action with the cool and calm pump driver and his busy off-sider running madly about shuffling the hose. 

Leveling and smoothing

10:15 - The fifth truck is emptied and we are nearly there. There is alot of finishing work after this as they wait over a hour for another truck.

The pace slows as they approach the finish. Five trucks are ordered for the pour and they still need another for the garage.

10:40am - The concretors begin to remove the top edges of the formwork to complete the edge beam facing. This also avoids any lifting of the slab surface when the formwork is removed later. They refinish the alfresco and other areas that had stakes and frames within the slab surface (such as the ones shown in foreground on the porch dropdown).

11:15am - The final truck arrives and the garage is completed. 
 

11:45am - Keith is working the surface of the slab with the powered trowel. The slight imperfections on the surface created by the float start to disappear.

4:00pm - The slab is finessed to perfection. A few of the boys are still here tweaking the garage and filling areas. 

Quite an amazing result!

I hope to post some high speed video of the action sometime later this week.
Come back later this week to see the magic ;)

Formwork, Waffle Pods and Steel. Lows and highs of the week.

Week 3 of our construction program and we are at pre-pour stage of our slab.
Our Site Supervisor was spot on regarding the slab timing. Whilst on the phone with him on Friday, he confirmed the slab pour for Monday and he also advised the frames will arrive on the 28/8. Lets hope the progress continues to accelerate. This week has had its lows and highs, so lets catch up on what happened this week.

Monday (10/8)

As stated on my last update, I spoke with the Structural Engineer at RE about my concerns of covering the piers with soil. Rick assured me that this was not within design specifications. One of his team inspected the piers before pouring and they were unaware that additional leveling took place after pouring the piers. Suffice to say, Rick was unimpressed by my report. He assured me that he would speak with the concretors to clear the piers and make sure they are clearly visible on the final inspection prior to slab pour. 

I also discussed this issue with our SS, and he clearly stated he wasn't concerned. Mark advised that these experts' and contractors know what they're doing, and it's a certified solution so there are no surprises. Mark advised a fortnight ago that his contractors and engineers work closely together and he doesnt really get involved in this stage of the project. I wasn't really fussed about his attitude on the matter, but to be honest the problem is with his experts.

This isn't a SS issue. I'm on his side on this one. I just don't trust these trades like he does  ;)

Wednesday 12/8

Mid week morning update: Form work is 50% complete.

Footprint defined

Plumbers gravel

PVC and Waffle Pod delivery

I dropped by again in the afternoon.

Plumbing roughed in. There were also deliveries for the various types of reinforcing, mesh chairs, and the supplier arrived to deliver the waffle pods.

Thursday 13/8

This unfortunately is what I was worried about. Inch thick clay covering the concrete piers make the whole structure useless. I'm livid this hasn't been looked at.

Theres a pier there!

Friday 14/8

Much relieved today. I met up with the boys on-site and spoke with them about the piers. They had waited for the plumber to complete his work. They scraped back all the piers this morning and I could see piles of dirt around the form work. I'm not sure they would have done this had I not referred the issue to the engineers. In any case, all good now.

Checking levels and measurements

Waffle pod lay out

The boys have been busy this morning. Membrane down and sealed. Edge beam reinforcing. Edge lapping and pods getting laid out whilst I was there. 

The rentokill Contractor also turned up to install the barriers. These are the orange skirts on the PVC pipes.

Saturday 15/8

I dropped by late afternoon to have a look at the final formwork in preparation for the pour on monday. 

Front patio stepdown

Garage stepdown

Drop Edge Beam (DEB)

Rick stepping over the plan. Pink spray paint designates the pier locations.

No more than 2 minutes go by, and a guy pulls up and jumps out of his car. It's the principal engineer from RE, Rick. He dropped in after playing some sport in Ermington... at 5pm?. Wow. I'm impressed by this guy. He walks me through all the areas, and points out each item on the plan. He also refers to three things that he will pass over to the concretors.

1) Insufficient slab thickness on the drop edge beam (west side of the alfresco)

2) Waffle pods covering one of the central piers. This should be a reinforced beam, so they will need to cut out a section and drop some steel into it.

3) Formwork on the garage should protrude slightly on the western end to conceal the downpipe. This needs to be "locally widened".  

Early morning tomorrow. SLAB! I'm pumped... pardon the pun.

Piering and leveling

Once again, construction week 2 has seen a late surge of progress with earthworks contractors bringing out the concrete truck, pump and laser level.
There was no progress until Friday afternoon, when the boys arrived, drilled the holes and filled them with concrete. According to the engineering plans, piers are placed along the load bearing areas, drop edge beams/building perimeter and a few mass piers in the middle of the slab (keep reading to have a look at the engineering plan).

So the ground is cut from the front, distributed as fill through to the back and the soil is retained via Drop Edge Beams (DEB). We will need a step just beside the back edge of the garage and a single step out of from the laundry door. We also need a couple of steps on the back steps from the alfresco.
What appeared to be a flat level site when we purchased the site, is actually a site that slopes 1 metre in 14.
You can see the engineering specification below. Lots of piers!

Engineering Design - Footings, piers, waffle pods & beams. Dashed lines depict the lines of the steel formwork between the Waffle pods.

Filling holes

Saturday morning, the contractors return to level the site, clear the excess fill, and pack the fill. According to both the architectural plans and the engineering specification, the relative ground level should be an even 39.5m. This means an average 300mm of fill with the bottom corner getting 400mm of fill (DEB 400). This bottom corner feels loose and quite soft.

Soggy fill down in the Family Room corner of the slab. You can also see a 'scraped' pier in the top left corner.

 I had a good look at the site today (Sunday 9/8/15) and found that the leveling completed yesterday appears to have covered all the piers except those in the garage. I'll speak with the Site Supervisor to confer with the earthworks guys as to why the piers are not exposed. The engineering specification states "All piers, slab and footing reinforcement shall be inspected by the engineer prior to the pouring of concrete. Give 24 hours notice to the engineer". How can you issue a certificate for the design if you can't sight the piers?


Hmmm. where did the piers go? You can see in the pictures below, the piers appear to have been covered by soil.

Piers in the foreground, but where did the rest go? Where are the piers for the drop edge beam on that back edge/ fill?

A call to the engineer and Site Sup is on the agenda.

I must say, when i was sticky beaking at the other Rawson KDR in 'Oatlands' last weekend and I didn't see all the piers either. I was discussing my concerns with a good friend today, and I'm now resolved to get this cleared up. I just can't accept anything less than the engineering spec on the foundation slab.