Bridge demolition easier with modern machines

The speedy and safe removal of old or unwanted structures is made easier with modern, sophisticated equipment, Patrick Smith reports

The power and versatility of modern demolition tools and machines was demonstrated when a bridge was removed overnight as part of a motorway widening project. Armac Demolition successfully removed the farm bridge across the M1 motorway near the city of Nottingham, UK, where the 2309 Highways Agency's work to widen part of one of the busiest routes in Britain to four lanes is ongoing. The motorway was closed between Junctions 25-26 on Saturday night and Sunday morning, and a huge 'mat' was placed on the road to catch the demolition debris. Then excavators (five Cat 345, 58tonne; four Volvo 360, 36tonne; one ZX 650, 60tonne; one PC 600, 60tonne and three Cat 320s, 20tonne) using 6 and 7tonne breakers and 4 and 6tonne combi-crusher attachments swung into action.

Demolition of the 43m long, 42 year-old reinforced concrete bridge weighing around 600tonnes was completed before the 9am deadline on Sunday. The bridge was not wide enough to allow the extra motorway lane underneath, so it will be replaced with a bridge with wider spans. The contract to widen a 23km section of the M1 between Junctions 25-28 was awarded to Anglo-French joint venture MVM (3084 Morgan-Est, 3085 VINCI Construction Grands Projets and 3081 Sir Robert McAlpine) in January 2007, and work started in October and is expected to take three years.

Meanwhile, 161 Atlas Copco has said its high performing HB 3600 breaker is aimed at carriers in the 35-63tonne class, with the company claiming the hammer delivers 46% more performance for its weight than the average breaker in its size class while overall it offers 30% greater efficiency.

This is a new breaker size designed to match the increasing diversity of carrier sizes and provide a better size and performance
fit for carriers in the 26-63tonne class than existing models.

According to Atlas Copco the high power-to-weight ratio means that it will provide the same work output of a larger unit while using a smaller excavator, cutting initial investment and running costs. An efficient energy recovery system increases output power, without increasing the hydraulic input during peak periods. The breaker also features Atlas Copco's proven PowerAdapt, StartSelect and AutoControl, ContiLube II, DustProtector II and VibroSilenced systems, which combine to improve performance in all operating conditions, reduce wear and tear and cut noise output.

Cat's demolition shears

178 Caterpillar Work Tools has also introduced the new mobile scrap and demolition shears S320B, S325B and S340B series for hydraulic excavators, extending the B-series which also includes the previously released S365B and S385B shears.

"The performance and durability improvements will further build on the already excellent reputation of the S300 B shears" said Dave Becktel, commercial manager, Caterpillar Work Tools.

The company says that the robust shear and knife design improves cutting performance and the hardened piercing tip of the upper jaw maximises productivity when piercing is required. All S300 shear models are equipped with field-proven 360° rotators ensuring a quick and precise placement of the jaws in an optimum cutting position without moving the excavator. The high force-to-weight ratio enhances faster cycle times, resulting in more cuts per hour. The S320B, S325B and S340B series fit Cat excavators from 10tonnes to those in excess of 60tonnes operating weight, and they can be mounted on either the boom or stick.

Better breaker match

325 Sandvik's BR2577 is an addition to its hydraulic breaker range, and is suited to carriers in the 21-30tonne class. The 1.7tonne breaker replaces the BR2568 and has an impact rate of 450-750 blows/minute, and offers Sandvik's fixed blow energy system, which is said to ensure optimum impact energy with every blow, regardless of hydraulic flow rate.

Customers can choose from a range of options to match their application, material and budget, and these can be retrofitted to the hammer after purchase. They include a safety valve that protects the breaker from an inappropriate hydraulic installation, a system to protect against blank firing and a sensor that reduces impact power and frequency in soft conditions. Other options include the Ramlube automatic greasing system, Ramdata operating data package, Ramona performance monitor and Ramair dust suppression equipment.

The BR2577 features a tool diameter of 135mm, and has wear protected hoses and an efficient relief valve that provides extra protection to the hammer.

PicBucket 5000 Series

Canadian firm 3089 PowerTech says that its improved 5000 Series PicBucket offers increased productivity and performance.
PowerTech says the PicBucket can be fitted to an array of excavators (20-30tonnes) and it performs a whole set of functions that used to require all sorts of equipment, and is said to be effective as a conventional bucket and as powerful as a hydraulic hammer used in demolition, excavation, prying, ripping, backfilling and compaction, combined in one tool.

The patented integrated hydraulic cell technology helps it in demolition and material recycling applications, while a powerful hydraulic cell supplied by Atlas Copco allows the PicBucket to crush items such as concrete light poles containing rebar productively. Spanish company 3092 TABE is now offering a wider range of hydraulic breakers. The latest AGB-10, AGB-15 and AGB-18 units share the same design concept as the existing models and are designed for heavy-duty demolition applications.

The AGB-10 hammer weighs in at 950kg and suits excavators weighing from 10-16 tonnes, while the 1.47tonne AGB-15 is designed for carriers in the 19-25 tonne range.

The new top-of-the-range breaker is the AGB-18, which weighs 1.85tonnes and is designed for machines weighing from 4-28tonnes. Like TABE's existing breaker models, the hammers feature the firm's novel coupling system and have no tie-rods. This design makes the hammers more durable, more reliable and easier to service. In addition, the breakers have a range of features like automatic lubrication and pressurisation that are designed to extend life and reduce wear in tough operating conditions such as underwater demolition. With these introductions, the firm has revamped its entire product line-up and its light range features seven models weighing from 80-410kg and this includes the recently launched AGB-95, which weighs 105kg.

The company's mid-range weighs from 600-850kg and includes the recent 600kg AGB-575, which can be used on 8-15tonne carriers, while the compact Beta Breaker range was recently augmented by the addition of the 163kg unit, designed for carriers weighing 1.5-3.5tonnes.

Long reach excavators

176 Case is building special long reach excavators for markets such as demolition and scrap handling at a new facility at Zeebrugge in Belgium, with the specialised models available on the medium-large excavators in the line-up.

However, customers who want conversions of the 70-80tonne class Case machines into long reach demolition versions can source these through the specialist company Kocurek in the UK. Called Case Special Excavators (CSX), the Zeebrugge facility is to produce long reach, mass excavation, high reach demolition and material handling boom and dipper components.

Long reach versions of the 8-35tonne excavators will be available for the demolition sector, a market that Case is particularly keen to re-enter (the company was previously a leader in the market for specialist excavators when it built these machines in France but later moved away from this niche segment).

According to Case, the CSX operation will not be restricted to making longer booms. The modifications required to convert excavators to long reach demolition specification include revised hydraulics, heavier counterweights, wider track frames, stronger boom mountings and heavy-duty slew rings to cope with the greater bending moments generated by the increased reach. Other modifications for demolition specification machines include tilting cabs, new walkways and guardrails, extra cab protection and boom-mounted cameras.

New Holland's new line

A new line of demolition specific excavator models extends the 5895 New Holland line-up. The 38tonne class 385B and 45tonne class 485B machines are being offered in long reach demolition versions, while the company has developed a heavy-duty version of its 21tonne class 215B machine.

The 385B is offered with a high reach of 21m while the larger 485B has a reach of 25m. Both machines have additional cab protection and can be specified with an array of other heavy-duty features to suit the demolition application. A new departure for the firm is the 215B demolition excavator, which is designed for ground-level clearing up and breaking duties and to work alongside the long reach machines. The 215B has a standard length boom and dipper.

'Designed-for-purpose'

Volvo Construction Equipment (359 Volvo CE) says its new EC360CHR ultra high reach demolition (HRD) excavator is seen as a further sign of the company's commitment to the demolition sector.

With its 21m of reach, the EC360CHR (operating weight without attachment is 43-46.3tonnes) joins the existing 32m reach EC700BHR, and is set to be followed shortly by the launch of the 27m reach EC460CHR.

"Volvo is adopting a 'designed-for-purpose' philosophy in its demolition range, offering features demanded by the tough conditions prevalent in this sector and appreciated by customers and operators," says the company.

Supporting the HRD machine are six standard demolition machines, the EC210CLD, EC240CLD, EC290CLD, EC360CLD, EC460CLD and EC700BLD.

A key feature of the ultra high reach range of demolition machines are a hydraulic modular joint that enables a 30-minute quick change from demolition to standard backhoe attachment, aiding high machine utilisation when not required for high reach projects. Volvo ultra high reach machines come with both demolition and digging boom and arm, with transportation cradles for both.
The standard, hydraulically tilting cab with up to 30° tilt enhances operator visibility when working at height and reduces fatigue and neck strain on high reach jobs, while the optional, extendable undercarriage expands by 1m to ensure a more stable working platform and a 360° working radius.

Hydraulic capacity and flow power high reach attachments such as pulverisers, severe-duty grapples, hammers, shears and multi-processors, and there is a 2.5tonne tool weight capability on EC360CHR and EC460CHR, and up to 3.5tonnes on the EC700BHR.

Komatsu's HRD machine

2300 Komatsu says its PC450HRD-8 crawler excavator brings all the benefits of the Dash 8 range into the specialised demolition industry.

With a maximum working height of 27m, the high reach demolition machine is fitted with large boom cylinders to help to give the operator maximum hydraulic power at all times for total control during precision work, even at extreme reach.

"The Komatsu electronic Closed Load Sensing hydraulic System (CLSS) offers complete control during both single and simultaneous attachment movements," says Komatsu.

The wide gauge undercarriage can be either mechanically or hydraulically adjustable: the hydraulic adjustable undercarriage offers a minimum transport width of less than 3m, and a maximum stability width of 3.9m for the job site.

The machine is fitted with a three-section boom and for minimum disruption and maximum machine usage time, the Komatsu-developed and tested quick-change system allows the PC450HRD-8 to be quickly reconfigured from HRD demolition to medium and low reach demolition or to a digging configuration.

Optimum model

233 Hitachi Construction also offers equipment for HRD purposes with its long reach demolition front, which it says is useful for demolishing tall buildings and structures. The maximum arm point is 13m to 50m. The optimum model can be selected among models for object height.

Three types are available for this front: three-piece front and two-piece front type which are exclusively for demolition, and crusher-backhoe type which can be used as a crusher and backhoe excavator by changing the front.

JCB's Multiprocessor range

Legislation means the recycling of demolished materials is now an area of major importance for demolition contractors to consider.

At the forefront of 255 JCB's demolition is its range of purpose-built tracked excavators offering XD (Extra-Duty) versions of its JS220 and JS260 excavators which feature alongside the successful high reach demolition rig for the JS330XD model. Among the latest additions to its attachments  are two new ranges developed in response to changing trends.

JCB's new Multiprocessor range features three models: the MP200, MP300 and MP400 which are ideal for 'reverse construction' (their accuracy and versatility allowing materials to be removed, processed and separated by one machine whether on primary or secondary stages of demolition).

JCB says that not only is this cost effective but also enables the different materials to be recycled. The MP200, MP300 and MP400 have operating weights of 1,680kg, 2,580kg and 3,480kg respectively and are compatible with excavators from 15 to 50tonnes. Enabling similar performance, the new JCB SG (Selector Grab) sorting and demolition grab range has been designed to deliver increased productivity when handling construction, demolition and general waste.

The range comprises seven separate models, compatible with JCB's 10-46tonne excavators, which enable the operator to select, handle and place a wide variety of waste materials more accurately to enhance operational efficiency.

For breaking tasks, the extensive range of JCB Hammermaster hydraulic attachments offer a wide selection to suit both JCB and competitor machines, and are used in utility work, building and construction, demolition and secondary breaking, quarrying or mining.