DAMBAI BRIDGE PROGRESS ON 2ND MAY 2014

I got a feedback on this blog that my comments are too technical. Actually, after leaving the technical world for the last 2 years, I myself can hardly use technical terms or even name the parts of the bridge. However, should any readers have any questions, I will try to answer them, or make additions by editing the relevant post.

 Well, as usual I will monitor the Bambangan.  Hopefully if the fruits can grow, I may just ask the owner for a few ripe ones, that is if it can grow to maturity before the roots of the tree give way to the clay around it and dies.
For the moment I think the fruits have not reach one inch in size yet.

The formwork for the prestressed concrete beam have now been fixed. Note that it is made of prefabricated steel plates which is then joined together with bolts plus some extra supports just to prevent it from tumbling down during the filling up with concrete. As of today concreting work has not begun because the supporting bars are not fully installed according to the workers.

 Here you can see that the steel formwork is sufficient for one beam only and there are 5 beams for the two lane bridge.  Therefore the concrete for the first beam will have to set before the formworks are removed and re-used for the next beam and so forth. This type of concrete beam design must come in pre-selected sizes otherwise the production of the steel formworks would become an expensive business.
Also note the steel reinforcing bars juts out from the top of the beam in a T shape form.  This part will be connected to the concrete bridge deck or slab once the beams are installed on top of the pile caps. The beam and slab then become a composite single structure.

Foreground, the workers have added the rebars to the final height of the pile caps where the ends of the beam will be laid on.

background:  the works for the retaining wall continues.

BRIDGE PROGRESS ON 28 APRIL 2014

Workers installing the steel end caps for the prestress concrete beam

Seems that there are 12 strands of cables in the top duct while the bottom one has 18 strands.

Rebars and formwork for the pile cap cum abutment at the left bank

At the right bank, the installation of rebars for the concrete retaining wall had commenced

It was a hot day on the 28th April but this time the river water is flowing with red clay. Some earthworks must be carried out upstream

BRIDGE PROGRESS 20 APRIL 2014

The Bambangan fruit is still small but growing.

Full view of one whole span of prestress concrete Beam

How the ends of the top and bottom cable is installed ( hooked and embedded) at one end of the concrete beam

End for mid cables sticking out of the cable duct which will be used for tensioning the cables later

Workers jointing the cable ducts, simple screw it and tape it.

The other end of the Beam where top and bottom cables are jutting out of the ducts that will be tensioned later, just like the tendons of your muscles !

Embedding of the ends of the middle cable,

Rebars for the left bank pile cap cum abutment

At right bank, earthworks continue to give space to the retaining wall

Left bank showing gabion protection works for the bridge piles, and the clear water in river during dry hot spell

Bridge Progress Photos 7 April 2014

First of all, the flowers of the Bambangan tree seems on their way to become fruits.

Left bank, the preparation of the rebars for the prestress beam

And preparing the formworks for the left bank pile caps

Right bank, earthworks and clearing to provide space for the retaining wall

Fabrication of Prestressed Concrete Beam near the site 16 to 20th March 2014

The road reserve site infront of Mr Majawin's house was levelled with road quality crusher run and used as the fabrication site of the 30 m long prestressed concrete beam for the new bridge.
The bottom width is 660mm forming the lower flange, while the top is 410 mm.  Forgot to note down the thickness of web.
The overall depth of beam is about 2 m, while the designed weight is 45.4 tons using grade 50Mpa concrete. There are three strands of steel prestressing tendons of 15.2mm diam to be placed at the lower half. More photos will be taken once these are placed into the beams.
For the time being the workers are only preparing the forms and the rebars on site as per below.

2 pics above taken on 16 March 2014

These two above taken on 20th March 2014

STAGING and Construction Area for the Post Stressed One span Concrete Beam

The bore piling machines and cranes have long been demobilsed from site, athough the supervisor told me they will come back when the old bridge is removed and a new one constructed.

So JKR then reclaimed with clay and topped with road quality crusher runs the approach to the bridge as staging area for the concrete beam.
On 6th March 2014, they have started preparing the form-work support as shown in the photo below:-

Then they discovered that the foreground part as shown above is too low, not level, so they removed all these timber, filled the area with more crusher run and repeat the construction of the timber base for the concrete beam formwork.

Photos taken as on 13th March are as below:

So this was reconstructed.
Well I got this info from the workers themselves.

And at the same time the Majawin Bambangan tree is also very sad that her root area have been taken over and soon she will have to be chopped down.  So she protested by giving out the most beautiful red flowers for fruits. Although I am very much doubtful if the flowers will eventually produced fruits due to the very dry season for the last 4 weeks and even if it rains, the moisture no cannot reach the roots of the tree any more due to the impervious clay layer.

This type of tree needs to grow at least 15 years before it can bear fruits..Now all of us have to say goodbye to the ole Bambangan tree of which the fruits can be turned to pickled fruits or eaten like a mango if the species is the sweet type.

CLOSE up of the fruit flowers


Meanwhile, the workers prepare the top of the giant bored pile for preparation of pile cap for the bridge.

Bridge Progress Sunday 16 Feb 2014 - GOODBYE TO BAMBANGAN TREE

The contractors crew were also working on Sundays. When I asked them why, they said that the fine weather in the morning must be taken advantage to carry out the earth filling and compaction which was done in layers as per standard engineering procedures.

True enough by 2:30 pm it started drizzling and continued to light rain until midnight.

However much work was done in the morning filling the road area approaching the bridge at the left side which will initially be used as staging area for the fabrication of the steel beams for the bridge.

JKR has also widened the road reserve for highway by acquiring about 3 m width into the land lots near the bridge as shown in the photos. In doing so a majestic bambangan tree has to be cut down.

Two views of the Bambangan Tree belonging to the Majawin Family ( light blue house behind)  that will have to be cut down. Even if it is left at the edge of the road, it will still die because the roots have been filled with that red clay earth on top which drowns the root system.

Additional land acquired from the existing house lots as can be seen by the new location of fence wall from the old one. Land owners along this highway again have to sacrifice a slice of their land for the sake of the highway.

Earth filling works... good and dry working area in the morning on Sunday.

 

All works on the bored piles were completed as of this date

 

 

The staging area for the fabrication of the steel beams for the bridge.