When I was preparing a Bahrain Tender, I saw a lot of different type of concrete curb in the drawings. They had different shape in different situation, and the concrete curb had different name in different situation such as Standard Kerb (Pedestrian Crossing), Standard Upstand Kerb and Standard Kerb Laid Flat. It’s all precast product and it can be constructed in a short time and low cost. I will be explaining all of them in this article.

Type Of Standard Kerb

1) Standard Kerb (Pedestrian Crossing)
Pedestrian crossing kerb will be used when there is a drop occurred on the roadside for Pedestrian Crossing or we called it Zebra Crossing. The depth between the kerb and finished road level is about 25mm thick only, the kerb will be slowly slim down and end up the depth is same with the finished road level. The 250×125 half battered kerb will be used in this situation. It’s a type of dropped curb that used on the pedestrian crossing.

2) Standard Upstand Kerb
Standard Upstand Kerb is a normal type of concrete curb that used on roadside. When there is a Pedestrian Crossing, Standard Upstand Kerb will be joined with the Standard Kerb (Pedestrian Crossing) as what I mentioned above. 250 x 125 Half Battered Kerb will be used. The depth between concrete curb and finished road level is about 150mm thick.

3) Standard Kerb Laid Flat
Standard Kerb Laid Flat is a very wide but thin concrete curb. The depth between concrete curb and finished road level is about 25mm thick only. Same as Standard Kerb (Pedestrian Crossing) and Standard Upstand Kerb, 250 x 125 Half Battered Kerb is used too.

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There is many different types of concrete curbing machine in construction area. They have specific curbing machine for specific usage, normally it’s used for such as for garden, yard, roadside, side of bridge and etc. The function for the road curb and landscape curb will be slightly different, but the concrete curbing machine to be used might be almost similar.

Concrete curbing machine has many features, you have to find out what is their standard specifications and functions when you decide to buy a curbing machine. I’ve gone through to make another short list of concrete curbing machine, I hope it helps you.

List Of Concrete Curbing Machine

1) Curb Machine Kit With Forms

Features :
i) It’s used to construct concrete curb for landscaping, sidewalks, driveways and etc.

ii) The curbing machine come with three molds, which is flat mower style, curb style, and slant style.

iii) Able to run on 115V/60HZ.

2) MC 250 Landscape Curb Machine

Features :
i) Can be used in variety of location like golf courses, parking lots, recreation areas, water retention areas, garden borders and also miniature putting greens.

ii) Very fast in productivity, it can produces 12 feet of concrete curb in a minute.

iii) There is a large hopper with anti-bridging design improves the machine productivity.

iv) Easy to carry. The size for this curbing machine is small, the lifting bail makes it easy to lift the curbing machine too.

3) MC 350 Landscape Curb Machine

Features :
i) It’s similar with MC 250, but it’s designed to be used for decorative landscape curbing and smaller commercial curbing.

4) MC 550 Tack Down Curb Machine

Features :
i) It provides economical method of placing free standing, high-density extruded curb from either concrete or asphalt.

ii) The auger is changeable to provides largest range of curb sizes.

iii) This curbing machine is only for heavy duty. It can produces very smooth and stable concrete curb.

5) MC 1050 Slipform Curb & Gutter Machine

Features :
i) It can produces the concrete curb in fast speed which is 12feet per minute.

ii) It’s suitable to be used for commercial and residential curbing works which has limited duration to complete the curbing works.

iii) It’s easier to move and carry with tandem axle trailer.

6) Acu Edge

Features :
i) It’s a very high production curbing machine with its’ speed.

ii) It’s very stable and produces smooth and neat concrete curb.

More Concrete Curbing Machine : List Of Concrete Curbing Machine

* Thanks to all suppliers for providing the useful information to www.Concrete-Curb.com.
Curb Appeal USA | Miller Spreader | Harbor Freight

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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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