Expando Articles

Energex - Removal Of A Concrete Slab

John Rothwell Director of No Blast Pty Ltd - Tuesday, August 05, 2014

When I was contacted by Adam Philippini, the Construction Coordination Officer for Energex (an Australian energy provider) to remove a concrete plinth from their basement yard, I knew that Expando Explosive Mortar was the perfect solution for the job.


The concrete plinth needing removal was being used as a base for a transformer, the slab itself was approximately 1 metre thick by 3 metres wide and 10 metres long.


Given the location and size of the plinth, removal was not going to be a straight forward demolition job, this is one of the reasons that Expando was an excellent choice.


The slab was between two buildings where there could be no vibrations, minimal dust and no airborne concrete chips, this mean that traditional demolition methods such as  pounding the concrete with an evacuator was not an option.


After researching alternative solutions, Energex decided to use the unique non explosive demolition method that Expando Expansive Mortar provides, it was also chosen due to the cost saving provided over other demolition options.


To carry out the concrete demolition, Energex loaded Expando SCA-2 into holes drilled 38mm wide, approximately 450mm apart and around 850mm deep. 

The chemical started to crack the slab early on the second day after application, the weather was warm which helps with a quicker concrete burst.


To further speed the process and to ensure the reinforcing was cut, Energex decided to run diamond saw cuts along the slab, as you can see however in the images below, these cuts were not necessary as the job was completed entirely by the chemical expansion.


Expando Expansive Mortar ensured a safe and effective means of demolishing the concrete slab, with none of the usual concerns that need to be considered with demolition in a busy area.


Energex have been very happy with the result and will continue to use Expando in future jobs. 

Granite breaking in Wagga

John Rothwell Director of No Blast Pty Ltd - Sunday, February 09, 2014
Granite is always difficult to remove  because it is so hard. It takes an excavator an extreme amount of power with a breaker to hammer it out. Even Granite floaters cause moil breakages.

So when Justin Porganyi of Excell Gray Bruni working in Wagga NSW came across a series of Granite boulders buried in a future roadway they realised they were in for a tough time. They tried three hammers but were not making good progress and knew they had to find an alternative to the traditional rock breaking methods.

Justin went online to research for a cost effective rock removal method and found my product Expando. Which is a non-explosive demolition agent that cracks rocks and concrete. Justin called me to see if Expando would crack Granite, I assured him that I had used Expando myself on Granite rock with great success.
 
Justin was surprised how effective Expando was, as he told me they destroyed 1 moil prior to Expando and got a new hammer in for the 30t excavator to help break-up the rock after Expando had done its trick.  It only took them two days to crack the Granite from the time they drilled the holes and poured Expando in (The large section of rock in the photo cracked over a weekend.
Justin and his crew were new to using a chemical cracking agent however due to the great result they have ordered more Expando to crack the Granite further down the road.

Expando comes through for Ausgrid

John Rothwell Director of No Blast Pty Ltd - Tuesday, June 05, 2012

Bruce Johnson from Ausgrid to was searching for a way to demolish their existing Electrical Pits carrying live wires using as little vibration as possible in order not to damage the cabling.

They tested Expando on a mock up pit to see how effective the chemical was in breaking the pit without damaging the cabling inside. During testing we found out that within 100mm of the filled holes of Expando the surrounding concrete didn’t get more than 3 degrees hotter than when we commenced the trial. Expando effectively broke the concrete without heat damaging the electrical cables.

The results were a huge success.


(Click on the images to make them larger)

Underpinning using Expando

John Rothwell Director of No Blast Pty Ltd - Tuesday, June 05, 2012

Michael from MGB Constructions used Expando for rock breaking on a recent job under a house in Cammeray in Sydney.

He turned to chemical breaking for three reasons; the inaccessible nature of the work area; the hardness of the rock; and the fragile nature of the existing structure.

In the photo’s you can tell how hard the sandstone is due to the purple colour showing in the rock. When Michael’s team was drilling the rock was causing sparks off the drills.

All the drilling was done using 32 bore holes on 3-400mm centres.


(Click on the images to make them larger)

Expansive Mortar, Non Explosive Demolition Agent - Breaking Granite boulders using Expando

John Rothwell Director of No Blast Pty Ltd - Tuesday, June 05, 2012

Expansive Mortar, Non Explosive Demolition Agent from Expando

Pan Civil was engaged to widen the road and remove boulder hazards from the road shoulder in the Moonbi Hills region of NSW.

The rock was granite and extremely hard. Some of the boulders were up to 200 Tons. Neil Champion director of Pan Civil said “It was uneconomical to break these rocks using the hammers on our excavators. So we turned to Expando.  Drilling was done by hand and by machine. The splitting was taking between 24 and 72 hours depending on ambient temperatures”.

The photo’s Neil provided are great examples of what can be done using Expando.


(Click on the images to make them larger)

Tunnelling a horizontal shaft through Sydney Sandstone

John Rothwell Director of No Blast Pty Ltd - Monday, October 31, 2011

We are now involved in a small residential tunneling project in North Sydney. The owner is in his early 70s and knows that in the future the 38 steps from his gate to his door are going to become a really big obstacle. The project is to cut a tunnel through the rear of the garage under the front lawn and then under the existing lounge room, where a small elevator shaft will connect the vertical shaft to the horizontal tunnel under the front lawn. The project has been a hobby for the former mining engineer.

Due to the cost and time taken to excavate the first five meters of the tunnel we have been engaged to help. The challenge has been to fill horizontal and vertical holes using the chemical Expando. We initially used a grout pump to fill the horizontal holes but the cost of hiring was too expensive for this residential job so we came up with an alternative method.

We have been filling long skinny bags with the chemical Expando and forcing the bags into the horizontal holes using a PBC pipe and Timber ream it has had the same effect as if we had poured it into the holes from the top.

We are now far enough under the house that we can start cutting in the vertical shaft .Holes have been drilled up from the lower tunnel and as we remove the rock from the top we can simply drop it down the hole to be cleaned out through the garage. 

(Click on the images to make them larger)

There's No Such Thing As A Good Vibration

John Rothwell Director of No Blast Pty Ltd - Tuesday, September 20, 2011

Case Study At Liney Point

Expando at Liney Point Case Study

Difficult sites and issues with vibrations are now a thing of the past thanks to an innovative product that’s been tried and tested overseas now it’s finally come to Australia. Expando – a non explosive demolition agent, is suitable for difficult sites where vibrations and noise are an issue and those with a high concentration of rock or for confined spaces.

Expando, owned by a local Australian company, No Blast, is currently being used to excavate a site in Linley Point that will eventually become one of Sydney’s largest and most innovative homes. 

The development began with the demolition of two neighbouring waterfront homes that were situated on a steep precipice of rock descending to the waterline at the southern point of the bay. The terrain the houses were built on and the sheer size of the development meant the removal of a momentous amount of rock. Excavation has already been underway for nine weeks and there’s still another six weeks to go before it is cleared, leveled and ready for phase two. 

So with a project of this magnitude, where do you start? Stephen Johnson, owner of SJ Constructions, who has taken on the planning, design and development of the home, begins ‘For the first few weeks we went about the dig in the traditional way using an excavator but the noise and vibrations from the continuous thump of the excavator was affecting neighbouring properties so we stopped the dig and went about finding a less intrusive excavation method.’ 
 
‘When water freezes, it expands that’s why when water that collects in road cracks turns to ice in winter it enlarges those crevices into gaping potholes.’ I knew there had to be a man made solution out there that behaved in a similar way so I started a Google search and found a non explosive expansive mortar called ‘Expando’ from a local Australian supplier.’  

‘The owner of Expando, John Rothwell delivered the first load and demonstrated how to use it. It’s idiot proof really, easy to mix, non toxic so there’s no license requirement for careful handling and no OH&S issues.’ 

‘Because of the enormous scale of the project we wanted to make sure we had the best and most cost effective technique before we commenced, so we began experimenting with the size and spacing of the holes before we were satisfied we had the best method down pat.’
 
‘We start by drilling the holes and then we fill them at different times of the day so the rock cracks in sequence. We fill the holes at the face of the rock in the morning and work our way backward. The face cracks and falls, then the next level back goes and so on. We then use an excavator once a day for final removal offsite, this reduces the impact noise and vibrations have on the neighbours and allows us to continue working on the dig throughout the day.’ 

‘We use 20kgs of Expando per seven 1.6 metre holes, 38 millimeters in diameter – that’s 2.3 cubic metres of rock removed per 20kg box.’ 

Now you have discovered Expando, would you use it on other projects? ‘Definitely, it’s perfect for confined spaces such as drilling under a house, or whenever vibrations or noise is an issue. It’s also great having a local supplier that you can call upon. The site can only store a small amount of material so John makes regular trips to deliver more Expando’.  

So what will the development eventually look like? ‘We are still planning the finishing touches but eventually this will be a 3000sq metre home which comes complete with a ballroom, 20 seat home theatre, indoor / outdoor swimming pool, a bowling alley, 120,000 litre fish tank, and a badmington court. It will take two years to construct and we are aiming for a 7 star rating BASIX rating’. 

(Click on the images to make them larger)

Expando - Ideal for building green

John Rothwell Director of No Blast Pty Ltd - Sunday, September 04, 2011

Explosive blasting, ignition of dangerous gases and heavy equipment - these are the traditional methods employed by mining, building & construction and civil engineering for quarrying, demolition or rock removal.

As these industries face escalating urban and natural environmental concerns including the unnecessary destruction of natural habitats, disruption to surrounding wildlife and proximity to residential or cultural heritage areas such as schools and hospitals, Expando has arisen as an environmentally friendly, non-toxic alternative for breaking rocks and concrete.

Expando, a non explosive demolition agent is used throughout Australia for concrete cutting, rock breaking, trenching, concrete demolition, excavation of ground rock and quarrying of valuable slabs such as Limestone, Granite, Sandstone and Marble.

Expando is noiseless, easy to use, reduces labour & equipment costs, doesn’t cause flyrock, ground vibration, gas or dust and is safer than explosive demolition, blasting rock, jack hammering, concrete saws or stone cutters. Expando does not produce fumes or gaseous emissions that could potentially harm the environment or disrupt surrounding work operations, equipment, filtrations systems or the air quality. This makes Expando ideal for sites with noise restrictions, confined spaces or environmental pollution concerns.

Expando is made from organic ingredients including calcium oxide, quartz, Aluminium oxide and Ferric oxide, is odourless, non-flammable, doesn’t cause toxic pollution and can be safely washed away after it has been used.

  • Made from organic ingredients
  • Odourless
  • Non-flammable
  • No ecological contamination to flora or fauna
  • No dust contamination
  • No toxic pollution
  • Environmentally friendly

When mixed with water, Expando has an impressive 14,000 PSI expansive strength, producing significant pressure to fracture and break up rock or concrete in a controlled fashion. Much less energy is required to break the rock in this way, and therefore less must be dissipated on breakage.

Because of its ability to reduce the destructive impacts on the environment that other traditional methods cannot deliver, we believe that Expando is an ideal product for greener buildings and houses.

Reduce construction vibration with Expando

John Rothwell Director of No Blast Pty Ltd - Saturday, September 03, 2011

 

As the building and construction industry faces escalating urban density, natural environmental concerns and proximity to cultural heritage areas such as schools and hospitals, controlling construction vibration can be a nightmare.

Complaints from neighbours, council restrictions, crippling project budgets, and damage to adjacent buildings are some of the common impacts from vibration issues.

Now an innovative product called Expando has provided a solution for these difficult sites. Expando – a non-toxic expansive mortar is the ideal solution to crack rocks and concrete without the headache of vibration issues typical of traditional demolition and rock removal methods.

Expando is a non explosive demolition agent with an impressive 14,000 PSI expansive strength that will simplify the process of cutting and breaking rocks or concrete and takes the risk out of difficult excavation, trenching or demolition work.

By using Expando, you can save thousands of dollars and achieve your demolition objectives without having to hire expensive experts or specialised equipment like excavators, jackhammers, concrete saws or use explosive blasting.

Why is vibration an important issue?

Construction vibration levels are set by regulatory authorities such as each state’s Environment Protection Authority (EPA), Standards Australia and local councils*.

The need for such regulation arises as construction equipment (including pile drivers, jackhammers, dump trucks, dozers, excavators and concrete saws) can operate in very close proximity to residential and commercial premises, sometimes for extended daily hours and for some projects, in excess of two to three years. If vibrations are a potential problem, councils may require a dilapidation report on neighbouring properties as part of DA approval.

If vibration levels from construction are too high, then people residing or working nearby may take action or involve councils to restrict construction activities, especially if it can be demonstrated that levels exceed acceptable limits set by relevant standards and regulations. As such, construction vibration can threaten a project's schedule and budget if not adequately addressed.


Vibration – Some of the impacts


Neighbour Complaints due to Human Disturbance

Vibration can potentially impact on an individual’s quality of life or work efficiency. This is especially true for project sites within close proximity to residential or cultural heritage areas such as schools and hospitals.

The vibration criteria for human disturbance tends to be more stringent than for effects on building contents and building structural damage. The table below shows vibration limits for normal construction activities to protect human comfort based on NSW EPA's guidelines. These human comfort limits are intended to minimise annoyance and are below levels required for the prevention of structural damage to buildings (because people can feel vibration at lower levels than what is required to cause damage to buildings and contents)and as such, are considered suitable for use in general assessments.


Table 1 – NSW EPA Vibration Limits to Protect Human Comfort (rms)*

Place

Time

Continuous Vibration

Intermittent Vibration

Residential

Day

0.2mm/s

6.0mm/s

 

Night

0.14mm/s

2.0mm/s

Offices

Day

0.4mm/s

12.7mm/s

 

Night

0.4mm/s

12.7mm/s

Workshops

Day

0.8mm/s

12.7mm/s

 

Night

0.8mm/s

12.7mm/s


Below are some commonly used indicative minimum buffer distances to avoid human discomfort during the day. However, please note that as vibration level depends on many factors and is site specific, these should be used as a general guide only.


Table 2: Suggested Minimum Bugger Distances to Avoid Human Discomfort*

Activity/ Equipment Type

Min. Distance

Rock breaker  (small – large)

5m – 15m

Pulverisor 30 tonne

4m

Bulldozers

5m

Vibratory rollers (light – heavy)

5m – 25m

Truck movements

10m

Sheet piling

50m


Structural damage to buildings

Construction in dense urban settings can result in damage to adjacent structures. Even the most careful planning and implementation can result in damage if adjacent buildings are fragile or especially susceptible to vibration due to demolition and other construction activities.

Currently no Australian Standard exists for assessment of building damage caused by vibrational, however as a guide, the German standard DIN 4150 - Part 3 Structural vibration in buildings – Effects on Structures provides “safe limits” up to which no damage due to vibration effects has been observed for particular classes of buildings.


Table 3: Minimum Safe Limits of Vibration to Reduce Likelihood of Building Damage (rms)*

Building Type

Intermittent Vibration

Commercial & Industrial

20mm/s

Dwellings

5mm/s

Sensitive Structures (eg. historical with preserve orders, etc)

3mm/s


British Standard BS7385: Part 2 Evaluation and measurement of vibration in buildings also sets standards for assessing the likelihood of building damage from vibration.


Reduce construction vibration – Buy Expando today

When construction vibration is an issue for demolition and excavation work in residential settings or sites within close proximity to cultural heritage areas such as schools and hospitals, Expando is the ideal solution for you.
Expando is a non explosive demolition agent that cracks rocks and concrete without the need for blasting or heavy equipment like excavators, jackhammers or concrete saws.

Buy Expando now via our secure online shop, delivered anywhere around Australia. For more information on Expando expansive mortar please contact us.