The History of Tower Crane

Project Management

Site Layout Planning

A well planned site layout is important in locating plant and equipment, site offices and work areas within site boundaries and existing contour levels. This is critical in completing a construction project on schedule in a safe and efficient manner. Site layout plan and locations of site offices are shown in this section.

This is an example site layout plan.
This plan normally done before the commencement of site work.

Site Services

Temporary site utility services are necessary for any construction projects, e.g. electrical supply, water supply and telephone cable set-ups.

Selection of Tower Crane

Selection Criteria for Tower Cranes

The choice and utilization of a tower crane requires considerable planning. It showed reach from its fixed position to all locations from which loads are to be lifted and placed. Therefore, when selecting a crane for a particular project, the engineer must ensure that the weight of the expected loads can be handled at their corresponding required radius.

Tower cranes are selected for use based on factors such as:

1. Weight, dimensions, lift height and radius of the heaviest loads

2. Frequency and duration of usage

3. Maximum free-standing height of the crane

4. Maximum braced height of the crane

5. Machine-climbing arrangement

6. Weight of crane supported by the structure

7. Available headroom which can be developed

8. Area which must be reached

9. Hoisting speed of the crane

10. Length of cable that the hoist drum can carry

11. Other normal procurement factors such as price, reputation and service back-up of manufacturer/ agent

Tower Crane Erection Process

Never seen of tower crane erection before? Here are the basic steps involved:

1. Pile driving work based on the design by engineer.
   
2. Cast a concrete base for the basic mast of the crane with timber formwork
3. Assemble the telescopic cage section on top of basic mast
4. Assemble the top mast section just under the mast cabin on top of cage section
5. Erect the section of top tower containing the mast cabin above top mast section
6. Fix the counter-jib perpendicular to the vertical tower using the counter-jib tie
7. Hang the counterweights at the end of the counter-jib
8. Install the main jib with the main jib tie
9. Hang the jib trolley on the main jib

After erecting the whole tower crane, it was ready for "raising" to the required operating height. This was achieved by jacking up hydraulically the telescopic cage section and then bringing extra standard mast ( 3m height )sections into the telescopic cage consecutively until sufficient height was reached.

The fixed base-type tower crane has its tower mounted on a foundation block. By the use of another (mobile) crane, the tower can be erected to its full height at the beginning of the project or the crane can have the mechanical capability, usually hydraulically, to raise itself, allowing for the addition of structural sections to the tower.

See how's the tower crane jacking process:

Burj Dubai Cranes

Dubai: Dubai's skyline is expanding and climbing higher virtually every day. Wherever you look there is one familiar sight: a crane hanging over the horizon.

According to statistics available, about 125,000 tower cranes are operating worldwide. Industry experts cautiously estimate that 15 to 25 per cent of the world's cranes are here.

Patrick Mullaney, Tower Crane Operations Manager for Select Plant Gulf, the heavy machinery arm of Al Naboodah Laing O'Rourke, arrived in Dubai three years ago to work on the new airport site.

On arrival he approached the Guinness Book of World Records to enter Dubai for the high number of cranes on the site at the time. "There were 50 cranes, all over the 12-tonne capacity. It's the most we've had at the site and we are just one contractor. We tried to get it in the Guinness Book of World Records, but they weren't that interested," said Mullaney.

Tower cranes used to build skyscrapers are put up in two days on average. "The tallest free standing crane we used was at Ski Dubai, which measured 92.5 metres," said Mullaney.

The crane at Burj Dubai will eventually be 750 metres above ground level. Laing O'Rourke is currently working on four big projects Dubai airport, Festival city, Burj Dubai and the Old Town and Atlantis hotel on Palm Island.

The construction boom in Dubai is very fast paced due to the overwhelming workforce and building around the clock. "At the most, we as a contractor had about 11,000 men working at the airport. Sites are just flooded with workers," said Mullaney.

"Tower cranes help the whole site. You can't do without them. Mobile cranes are limited because you keep having to move them. Tower cranes can be placed closer together and have a radius of about 140 square metres," he said.

More about Dubai

Burj Dubai, at the total cost of 900 million USD, this 705 m (160 floors) tower is one of the largest specialist projects in the world. The completion date of year 2008 depends upon collaborative efforts of construction and engineering expert.

Burj Dubai ( 116 stories ~ 400 meters tall ) in progress

Dubai in year 1991

* 110,000 tonnes of concrete were poured down to a depth of 50 m for its foundation. More than 50 passenger lifts will be at the disposal of residents and tourist.

Construction Industry Development Board Malaysia

All contractors, local or foreign who wish to undertake any projects in Malaysia need to be registered with [CIDB].

Fulfilling financial capacity and corresponding full time Personnel Resources Criteria according to contractor grade [G1-G7].

Note

* Paid Up Capital (for Private Limited Company/Public Company)

** Net Capital Worth (For Sole Proprietorship/Partnership) in the form of current account bank statement (average balance considered) /balance from saying account/overdraft facilities/uncharged fixed deposit statement/ASB/ASN shares

# Group A - Degree holder in construction related fields.
Group B - Diploma holder in construction related fields or other degree holder with experience in construction works.

Pusat Khidmat Kontraktor ( PKK )

Contractor in Malaysia are required to register under Pusat Khidmat Kontraktor ( PKK ). This is also a basic requirement for a contractor to get government projects. There are 6 classes of them which determine which project range a contractor qualify for. Normally contractor will aim for the class A in PKK to get an unlimited project tenders.

The above table shows the class and the project tender limitation.

The register and renewal frees that contractor need to pay.

Get more information about how on the regulation, application requirement and procedure [ HERE ]

ISO 9001

What is ISO 9001:2000?

ISO or the International Organization of Standardization is a worldwide organization that develops many different kinds of standards.

ISO 9001 is a series of documents that define the requirement for the Quality Management System Standard. ISO 9001 is one of the documents in this set; it contains the actual requirements an organization must be in compliance with to become ISO 9001 Registered.

ISO 9001:2000 is the current version of the Standard. It was revised in the year 2000. Past version of ISO 9000 included ISO 9002 and ISO 9003, but those are no longer in use. Companies are now only registered to ISO 9001.

Why do Companies want ISO 9001:2000?

Market Pressure
Many organizations decide to Implement ISO 9001 and obtain registration because it assures customers that the company has a good Quality Management System [QMS] in place. An organization with an effective QMS will typically meet customer expectations better than an organization that does not have an effective QMS. Many organizations require their suppliers to have ISO 9001 Registration.

Internal effectiveness and productivity benefits
Other organizations implement an ISO 9001 QMS because it has proven over the years that it leads companies to better operations, improved performance and improved profitability.

For more detail about the ISO standards. please [click here]

Quantity Surveyor

Quantity Surveyor, QS is a professional trained in construction costs and contracts. This profession required individual that able to meet tight deadline, work under pressure and work independently. This is normal and basic requirement in Construction field.

Their Scope of works are as per below:

• Do the taking off, site valuation and site measurement.
• To prepare monthly site valuation report and work progress report.
• To do cost estimation, comparison and tender preparation.
• To prepare claims and variation order.
• To attend consultant meeting, site meeting and project meeting.
• To manage and administer sub-contractors awards effectively and efficiently.
• To handle post-contract works as well.

Soil Treatment

Do you realize that the stabilization of soil is as important as the strength of the structural of the building that we construct? Yes, you should know that as most of the project involving of at least the piling work to stabilize the soil where the building gonna built.

Well, soil characteristic are so unique and need to be investigate to determine the properties of each soil. The bearing capacity, shear strength, and many more that will determine if the dream building can be construct. Mostly, Engineer will come out the solution for clients and it normally involve different construction method. In other words, soil can be treated.

Specialist is able to offer solutions to various geotechnical problems by applying different ground improvement techniques.

Some of the techniques are as per below:

Vibro Compaction is a method of densifying granular soils using a depth vibrator. The effect is enhanced shear strength and stiffness.

The particles of non-cohesive soil can be rearranged by vibration.

The Vibro Compaction process

Vibro Replacement is the installation of stone columns in clayey or silty soils using a depth vibrator. The improved soil matrix has higher shear strength and stiffness. In addition, the stone columns function as large diameter drains for rapid consolidation.

The necessity of replacement method for fine grained soils
(such as clays and silts)

The installation process of Vibro Replacement

Deep Soil Mixing involves the mixing of soft soils with a binder, typically cement and/or lime, by mechanical means. This treatment results in higher shear strength and stiffness.

Compaction Grouting is a technique that creates grout bulbs by injecting a stiff grout into the soil. This grout bulb displaces and compacts the in-situ soil.

Jet Grouting utilizes a fluid jet (air, water and/or grout) to erode and mix the in-situ soft or loose soils with grout. The result is significantly increased shear strength and stiffness. In sandy soils, permeability can be reduced to control water flow.

Bridge

Several Types of Bridge

Bridge building can be traced back several -thousand years. In primitive times, man used fallen trees, arches made of a rock fall and suspension. bridges made of vines and creepers to cross streams and ravines. These are the three natural forms of bridging methods, namely, the beam, the arch and the suspension structure. Despite the technological advances of the recent past, these three forms, either singularly or in combination, remain the basis of all bridge construction.

The vast majority of arch bridges were built with stone masonry. A few were also built of iron. Modern arch bridges are built with reinforced concrete.

Suspension bridges are used to form exceptionally large Spans. They are a highly specialized form of construction and far more expensive than beam bridges. Their use is therefore limited to a very small number of applications where their ability to span large distances is paramount.

Beam bridges are by far the most widely used form of bridge construction. They are applicable to small span bridges as well as. large spans of around 150m in prestressed precast concrete and spans of around 200m in steel box girder form. In certain circumstances larger spans have been achieved with these forms of construction. Traffic requirements in Hong Kong (and some other parts of the world) have made grade separation necessary at junctions. Generally, such grade separations require the construction of small to medium span bridges or flyovers for which beam type bridges are the most appropriate. The techniques of construction of this form of bridges will therefore be considered in detail.

System Formwork

My previous Project are using Transkon system formwork for the whole block shear wall construction. They are calling it Big Panel Wall Form. The formwork is fabricated with a 4mm steel faceplate and built-in stiffeners. Plumbing Soldier with catwalk is connected to wall form panel for access and bottom jack is used for vertically adjustment. Big Panel Wall Form minimizes panel joints and thus give a better concrete finishing. The Big Panel Wall Form consist of minimum connection of components and faster assembling. It's user friendly and produce a 100% dimension accuracy of finished concrete.

The disadvantage of this system formwork is that it is heavy and require crane to assist the erection and dismantling work. Besides, it requires a big space to temporary store the formwork before next erection. The contractor must applied the preferable mold oil to make sure the formwork surface is always clean and produce nice finished concrete wall surface.

Casting of the wall is in progress.

Radiused Wall

Transkon provide a flexform panel for the constrcution of curved wall witht the radius of between 3 to 20 meters.

The Climbing System

Climbing system are apply for the easy stripping and quick assembly time. Transkon Klick-Klack platform provides a safe working platform which eliminates the need of access scaffolding.

The climbing System are suitable for construction like lift shaft and staircase wall.

The Climbing system is crane handled and is easily plumbed and aligned. A minimum time of crane time is required to simply lift up the shutter and hook it onto the climbing cone which was casted into the concrete in the previous pour. The scissor action allow the formwork to be rolled back to enable the panels to be cleaned and oiled in position without having to lower the shutter to the ground or to the floor below.

Fast wall formwork erection without the access scaffolding.

SMART Tunnel Passes Test

The Star, September 6th, 2007

KUALA LUMPUR: The Smart Tunnel closure on Monday was justified because it was the first time the system was put to the test and proved effective in diverting floodwater, Smart project director John Abraham said.

“An alert from the Drainage and Irrigation Department’s Stormwater Control Centre (SCC) was received when rainwater reached critical levels at the monitoring station at 8pm.

“As a result of the closure, the tunnel managed to divert about 500,000 cubic meters of rainwater into the Taman Desa holding pond, keeping the water at a safe level of 28m at the monitoring stations,” he said during a press briefing at the Smart Motorway Control Centre in Jalan Davis, off Jalan Tun Razak, here yesterday.

The briefing was called in response to public queries on the necessity of the tunnel closure that resulted in hundreds of motorists being caught in a massive traffic jam.

He said although the rainwater diversion involved only the lower deck of the tunnel, the upper deck or the motorway tunnel was also closed for the safety of highway users.

The tunnel was closed at 9pm on Monday and re-opened at 5am the following day.

Abraham said the closure also gave the authorities the chance to put the system to a real test rather than basing its effectiveness on a wet-test. It also allowed the system to be fine-tuned.

“An important implication of the tunnel closure is that the system was able to divert rainwater away from the confluence of Sg Klang and Sg Ampang, to avert flash floods in the city.

“The level of water at the Tun Perak measuring station remained at 28m throughout the downpour, meaning that the tunnel helped to keep the water lower there,” said Abraham, adding that the river would overflow if the water level reached 29.5m.

He also said the system was able to give an accurate prediction of rising water levels at the rivers 30 minutes prior to it happening, while water levels at the 28 catchments areas were updated every five minutes.

The information was then relayed to the SCC before any closure instructions were given.

Stormwater Management & Road Tunnel (SMART)

The internationally acclaimed Stormwater Management and Road Tunnel project (SMART), incepted by MMC Berhad -Gamuda Berhad Joint Venture is a first of its kind in the world, incorporating both a stormwater tunnel and a roadway. The dual-purpose tunnel will divert floodwaters away from the confluence of the two major rivers running through the city centre while its central section will double up as a two-deck motorway to relieve traffic congestion at the main southern gateway into the city centre.

Slurry Shield Tunnel Boring Machine For SMART Tunnel:

The slurry shield tunnel boring machine consists of four main parts.

The first is the Rotary Cutter Head with tungsten pick bits used for excavation of soil and disc cutters used for the excavation of rock.

The second part of the machine is the Bulkhead located immediately behind the Rotary Cutter Head. This is where the pressured bentonite slurry shield is formed to provide stability during the tunnel excavation.

The third part of this machine consists of hydraulic rams, which are used to propel the machine forward and to keep the tunnel in its right alignment.

The fourth and the last main part of the machine is the tunnel lining erector used to install the pre-cast concrete lining of the tunnel.

Other parts complementing the main Special Features are two boogies on rails that house electrical, slurry pumping, ventilation equipment and cable and pipes.

The pre-cast concrete linings for the tunnel are transported continuously to the erector by boogies on rails. These linings are then hoisted and placed in the correct position in the tunnel with the help of vacuum pads attached to hydraulics arms. The arms are ex tended to keep the linings in place while the linings are bolted together.

The void between the excavated ground surface and the linings is immediately filled with cement mortar grout under pressurized conditions to ensure all the voids are fully filled.

For SMART, two Slurry Shield machines are used, both starting from the JKR field area in Jalan Chan Sow Lin. The first machine will head North under Jalan Tun Razak and Jalan Desa Pandan before terminating at the pond at Ampang behind Gleneagles Hospital.

The second machine will head south under the Jalan Chan Sow Lin and the KL-Seremban Highway next to the Sg Besi airfield before terminating at the existing pond in Taman Desa.

The Smart Tunnel operates in 3 modes:

Some of the Progress Photos:

Tunnel Boring Machine

I'm proud of human beings for the invention of the Tunnel Boring Machine [TBM] that give another construction method on mega underground project. Tunnel Boring Machines excavate tunnels with a circular cross section through a variety of geologies. They can be used to bore through hard rock or sand and almost anything in between. Tunnel diameters can range from a metre to 15 metres. Tunnels of less than a meter or so in diameter are more likely typically done by horizontal direction drilling rather than by TBM.

Tunnels Boring Machines are used as an alternative to drilling and blasting methods. A TBM has the advantages of not disturbing surrounding soil and producing a smooth tunnel wall. This significantly reduces the cost of lining the tunnel, and makes them suitable to use in built-up areas. The key disadvantage is the cost. TBM are expensive to construct, difficult to transport and require significant infrastructure.

Hydraulic Jacks Holding a TBM In Place Before Push It Forward.

Watch the video clip below to get an idea on how this TBM work. Or you can simply assume that this machine act like an earthworm.

Plant and Machinery

Exposure to the available of plant and machinery for site work are necessary for Project Department. Understanding the function of each machinery could minimize the wastages in term of time consume or even materials used.

Common List of Plant and equipment for earth works:

1. Excavators
2. Shovel/Bulldozers
3. Wheel Loader
4. Compactor
5. Motor Grader
6. Back Pusher
7. Backhoe
8. Forklift

World Tallest Building

Burj Dubai is Going to be the world tallest skyscraper.

The Burj Dubai Construction Site has seen on April 1, 2006 in Dubai, United Arab Emirated. It will be completed in 2008 and be the tallest building in the world at 162 stories high.

Tower Crane

How do you define high rise building.. Normally, 1-3 stories (low rise) 4-12 stories (mid rise) 12 to 40 stories (high rise) and 40 stories upward (skyscraper). For High rise building construction, you will see a huge crane standing firmly together with the building they build. They are normally called tower crane.. but for congested site, they might applying the luffing tower crane.

6 Tower Cranes


Tower crane with Flat Jib


Aerial view of Tower Crane


Tower Crane At night view

Luffing Tower Crane

Mobile Cranes

There are many types of Cranes available to suit our site work needs. For low rise building, we might only using the mobile crane or truck crane to assist our site hoisting work. There are many types of mobile crane itself. 16 tons, 20 tons, 25 tons, 25ton, 45 tons, 60 tons, 80 tons, 100 tons, 130 tons, 160 tons and 200 tons depend on local suppliers.. To determine which type of crane you need, you are required to know what are you hoisting and the site access cum condition. Experience will guide you to choose the idea crane for your site and to cut the construction cost as well.

P&H Mobile Crane

150 ton to 200 ton Truck Crane

Hydraulic Crawler Crane

Other than that, we got hydraulic crawler crane, ship cranes, offshore cranes, Tower crane, Luffing Tower crane and many more.. Find it out here soon

Dubai Mega Project

Palm Island


The World


Dubai WaterFront


Old Town: Gigantic Residential District

Hydropolis: underwater hotel


Burj Dubai: 800 meters high building with 160 stages


Dubai Marina: New city to lodge 120,000 people.