In construction project, almost all the civil and structure (C&S) project have bridge construction. C&S project consists of road works, drainage works, pavement works, bridge works and etc. In bridge construction, it requires specialist of bridge contractors to take over the bridge works because it’s a very technical works because it’s a large structure and must not has any error or mistakes occurred.

The bridge design must be prepared by expert engineer and assisted by consultant. The bridge design must be able to carry all the work load or vehicle load, or else it might be collapsed. There was many cases of concrete bride collapsed due to design fault or usage of unknown materials, which is not only happened in my country but many other countries.

Concrete bridge can be constructed by using prestressed concrete, either pre-tension method or post-tension method. Pre-tension method means the tendon has been stressed and plug in into the concrete bridge before doing concreting. Post-tension method means the tendon is stressed by the machine after it has been concreting in the concrete bridge. Prestressed concrete are very famous and mostly been used in bridge construction, the purpose of using prestressed concrete is to increase the strength of the tendon or reinforcement bar, so that it can carry and support the load on the concrete bridge.

How To Build A Bridge?

I’ll be roughly explaining on how to build a bridge. There will be 5 simple sketches about how to build a bridge. I get the sketches from my current tender in Bahrain. So, this will be the procedure of constructing a concrete bridge in Bahrain. The procedures are almost the same with my country, I think it’s the standard method and procedure of constructing concrete bridge for all the countries.

1) The bored piles for the abutments are installed. The bored piles are drilled into the soil, bored piles are used because of the status of the soil is not stable, so bored piles are used to strengthening the soil. It’s one type of ground treatment.

2) The abutments and wingwalls are constructed.

3) Bearings installed. Bearings are used to reduce the vibration when vehicle drive through the concrete bridge so that the concrete will not crack.

4) Submerged drainage pipes are installed as a drainage system to allow the rain water flows. After that, the channel below the bridge is filled with sand.

5) Superstructure is cast and prestressed sand removed. The superstructure also known as concrete beam. There is a few types of concrete beam like : U-Beam, T-Beam, cast-in-situ beam and also precast beam.

After that, all the necessary works like deck slab, pavement works, road works, parapet, railing and drainage works will be constructed. All the materials must be tested before it’s used to construct the concrete bridge so that the bridge contractor can construct a perfect and high quality concrete bridge. Cost saving is very important in construction but safety is the most important in construction as well.

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In construction area, many contractors do not want to follow what the client’s need or client’s instruction. Contractors do their own way without follow the design because of saving cost, this is the most serious problem that occurred in construction line. In my case, I faced a lot of similar problems in my project which the drainage contractor doesn’t follow the design and causes the drainage systems in trouble.

What Is Drainage Systems?

Drainage system is very important for a building, industrial area, housing area, and etc. Drainage is used to guide the rain water to flow into the right place. It’s used to avoid flood happening in that area. Most probably drainage is constructed with concrete, but there is also some drainage systems that installed with pipe or we called it piping system as well.

In construction, there is a drainage called Cascaded Drain. Cascaded drain is constructed on the slope, it’s constructed like a staircase and it’s constructed in steps. It’s very commonly used in my country, it’s very useful to be constructed on the slope to avoid slope failure due to overflow of rain water.

I’ll be explaining what is concrete cascaded drain and how is it going to be look like if it’s under designed, which is happened in my project site.

Before we can construct the concrete cascaded drain on the slope, we have to do excavation work so that we can install the formwork system to pouring the concrete.

The photo above shows a workman is installing the formwork system and concrete is going to be poured after the formwork system work is done.

This is what a concrete cascaded drain supposed to be constructed and the drainage system is working well. The steps are in 90 degrees and the speed of water flow can be slowed down when the water rain comes from top to bottom.

In the above statement, that’s a proper way and proper drainage system which is constructed on my other project site. I’m going to show you a failure drainage systems that has been occurred in my current project site. The failure drainage systems is due to the cascaded drain is under designed, the drainage contractor didn’t follow the design and even my instructions. It’s lucky that I’m still able to order the drainage contractor to repair the failure drainage system.

This is the concrete cascaded drain which is under designed. As you see on the photo and compare it with the photos above, there is no 90 degrees steps like the staircase. Other than this, the height of the sides for the drainage system is not enough and it’s not following the design. With that said, when the high volume of water rain and high speed of water flow, the drainage systems doesn’t perform well to slow down the speed of flow. In this case, when the high speed of water flow, the water overflow onto the side of the cascaded drain and we called it stone pitching.

This is the incident after a few days of high speed water flowing. The stone pitching on the side of cascaded drain fall down. The drainage system is totally fail because of the design error. In this case, we have a few months period, it’s like a warranty from contractor and we called it as “Defect Liability Period“, which mean that the drainage contractor have to ensure that the drainage system is working perfectly within that period.

So, I ordered the drainage contractor to repair the failure cascaded drain. Although it’s still not looking nice but as long as it can support the slope and has the ability to slow down the water rain flow. The drainage contractor doesn’t follow my design and repair in his own way.

After repairing of the failure cascaded drain, it looks fishy but it can still performs well. That’s the under designed drainage system, it may waste a lot of time and cost to repair it.

I ordered the drainage contractor to repair the stone pitching and rise up the level to avoid overflowing of high speed water rain flow. Other than this, I ordered him to construct a 150mm height of brickwall at the bottom of guardrail to protect the stone pitching and avoid the overflowing as well.

It’s not a standard design for a concrete cascaded drainage systems. Although it works well but everything goes wrong, we will be facing problem if the government doesn’t accept the design and we have to waste time and cost to re-construct the drainage system again. In construction line, many smaller contractors are trying to save their cost and trying to construct the works in simple ways and using cheap material.

As what I discussed with MAHAGURU58 in “Precast Concrete Road Curb” article, so called ‘con’tractors are throwing their reputation, they save cost and make a good profit but they lose their reputation. Reputation in construction line is much more important than money, you lose your reputation and you’re not able to get any jobs from client in public or private project.

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Recently I saw a concrete curb on the roadside and find out that the concrete curbing is installed with the steel barrier rail. As we can see, the steel barrier rail is installed on the top of concrete road curb, we rarely can see this type of road curb on the roadside because it requires a high cost for the steel barrier rail.

Purpose Of Using Concrete Curbing With Steel Barrier Rail

To construct concrete road curb together with steel barrier rail, it’s costly and rarely we use it. Of course, we still have to use it on certain area because of client’s requirements. Most probably we will use this steel barrier rail on the busy roadside, which means there is a lot of cars and lorries using the road. If there is many cars and lorries using the road, it may hurt the people who walks on the walkway. With that said, the steel barrier rail is to avoid cars and lorries drive onto the walkway and bang the passenger on the walkway, it’s very dangerous.

How To Construct Concrete Road Curb With Steel Barrier Rail

It’s not complicated to construct concrete road curb with steel barrier rail.
1) As usual, you have to just construct the road curb with concrete curbing machines. As you see, this is a cast-in-situ road curb but not a precast road curb, we can determine it from the shape. The photo below is the precast concrete road curb, it comes with smaller piece and in shape.

2) Secondly, install the steel barrier rail. Normally you can get it from steel manufacturer and it comes in shape. So, you just have to make it straight on the top of road curb. As you see at the photo above, there is a few post at the steel barrier rail, you drill with 4 steel screws on the post and attach it on the road curb. The same step for other post until you finish it. You don’t have to use stainless steel because the cost for it will be very high and might burst your budget.

3) That’s it, you have done it and it looks great!

It’s very simply and easy to install the concrete road curb with steel barrier rail, the cost is not high and you can protect the passengers on the walkway. Normally it’s required by your client.

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Concrete Curb is commonly used for roadside, it’s used to avoid flood and also avoid driver and motorist drive onto the walkway and hurt the people on the walkway. There are many type of concrete curb such as basic curb, combined curb and gutter, integral curb, kassel curb, precast curb, landscape curb and etc. Precast concrete curb is commonly used by contractor because it’s easy to construct, save time and cost, minimize the wastage of materials.

Normally concrete curb is used on housing yard or garden, it’s used to decorate our garden or yard. Most probably it’s covering the grass or tree to make it neat, clean and decorative. Few days ago, I saw this when I travel to somewhere, I saw the concrete curb was covering a type of red paver block.

As you see on the photo above, the concrete curb is surrounding the red paver block. There is few simple types of paver block such as interlocking paver, landscape paver and etc. Normally paver block is made from cement, concrete and aggregate. Many people likes to use paver block instead of laying concrete slab because it’s look unique and beautiful, house owner likes to use paver block to decorate their external floor as well. Manufacturer mix it with a few different of colour to make the pavers the look of natural stone, like granite or slate.

Red Paver Block – Made from cement, concrete and aggregate.

This type of concrete curb that surround red paver block is commonly used on the place where people want to make the place look nicer. Normally it’s used on walkway and people might walk on it. This kind of concrete curb with paver block, you can simply get some concrete contractors to construct it, it’s a very small job and most of the concrete contractors can done it well. The mixture of materials and colour must be correct so that the place can be look beautiful and great!

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Concrete landscape curb can be either precast or cast-in-situ. As what I mentioned in my previous article, cast-in-situ is those concrete that constructed on the spot on the site by labour. Probably concrete landscape curb is used to decorate our yard and make our yard to be different with your neighbours. Other than this, we call it as landscape edging as well. By using landscape edging for your yard, it makes your garden looks neat and clean as well.

Concrete landscape curb can be done by simple landscape curbing machine as what I show in “Concrete Curbing Machine List“. It don’t cost you a lot and it simple and fast to settle the job. It doesn’t like what I wrote for concrete road curb which curved combined concrete road curb and gutter takes you about few days to finish it.

Step By Step : How To Build Concrete Landscape Curb

I found a video from Youtube that we can learn how to build the concrete landscape curb for our yard, it’s a very simple video and it takes your 2 minutes to learn how to construct concrete landscape curb in short time.

1) Ground preparation
Ground preparation is meaning that we have to excavate a shallow with a hoe. After that, we have to make it flat and neat so that the landscape curbing machine can be move smoothly and done in short time.

2) Mixing concrete
After ground preparation, we may have to start mixing the concrete with a concrete mixer and bring it to the construction location.

3) Laying concrete
So we can now start laying concrete on the location that we want to construct landscape curbing. We will fix the landscape concrete curbing machine on the edging 1st, we need 2 persons to work on it if not the progress might be very slow. 1 person control the curbing machine and 1 person put the concrete into the machine. After put the concrete into the machine, another person will be pulling the curbing machine and the curb shape will be follow by the machine as what we saw in the video.

4) Finishing
The concrete edging is not as smooth as what we want, so we have to make it smooth with a tool. After that, we have to cut it into pieces.

5) Exposing Aggregate
In this stage, we have to expose the aggregate on the surface of curbing edging and make it stabilize and stand for longer without cracking.

6) Stamping
After that, we have to do stamping on the surface of the landscape curbing. The landscape curbing is now looks like built with small pieces of brick. The purpose of this is to make it unique and decorative. We have to do it unique because the main purpose of doing landscape curb is to make the place looks unique and decorative.

7) Spraying
Last, spray again with the aggregate and make it stable again. Done!

Conclusion

By building the concrete landscape curb, it only takes you a very short period to complete it. What you get is a very nice and unique garden, it totally looks different with your neighbours. The work is done in few hours time, it doesn’t make your place dirty and messy. It’s the easiest and simplest way to build the concrete landscape curb for your garden and yard.

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