InQuik revolutionises the future of bridge design

Established by Bruce Mullaney in 2015, and run by his sons Logan and Ben, InQuik’s innovative system enables bridges of varying lengths to be built from modular components. These components are manufactured in the Hunter Region and Brisbane, and can then be assembled by local tradespeople trained by InQuik. Gaining rapid momentum over the last few years, InQuik is set to oversee construction of its 70th bridge, with many more projects on the horizon.

constructsteel thanks the Australian Steel Institute for providing the information on the InQuik system. This article has been reproduced in full from Steel Australia, Winter 2020. Images: Snowy Monaro Shire Parsonage Creek bridge replacement is the largest project InQuik has completed to date.

A modular bridge construction methodology, the InQuik Bridge System was invented and developed by Bruce Mullaney, Logan Mullaney and Jim Howell in 2015.

The system is based on a standard reinforced concrete bridge methodology, which has been used around the world for more than 100 years. It is currently the most widely used bridge construction methodology in every country, especially due to advancements in pre-casting and tensioning cables.

The key idea behind the InQuik system is that a welded steel reinforcing cage is connected to a permanent steel formwork so that the construction load from the concrete is transferred to the internal reinforcing. thus, the structure is fully self-supporting and concrete can be poured on-site. This simple concept has numerous constructability and product quality advantages, and the structure has a minimum 100-year design life (achieved by using 40 mpa concrete, or 50 mpa in a b2 coastal environment), with minimal to no longterm maintenance requirements.

The maximum single span currently offered by InQuik is 18.5m. however, multi-span options are available, using the InQuik headstock to build bridges with no real limit on the total length achievable.

Revolutionising Bridge Design
As Bruce describes it, he and Jim never intentionally set out to revolutionise the engineering and construction of bridges. “My brother in-law Jim and I were developing a new fire-rated highrise housing system that used concrete suspended floors. When we looked at the drawings, we realised that the system could also be used as a bridge. And so our bridge journey began,” said Bruce.

InQuik was keen to work with other local companies from the outset. According to Logan, “We looked to team up with Australian companies to get off the ground. That’s one of the reasons why, in 2015, we partnered with SMEC —the originally stateowned company that built Snowy Hydro.”

SMEC undertook the engineering and certification work for the system. “Our engineers analysed the concept behind the system using advanced finite element analysis programs and adjusted our designs to be compliant with the relevant national bridge codes,” said Bruce.

As a result, the InQuik Bridge System was designed and certified by SMEC to comply with the requirements outlined in the Australian Standard AS 5100 Bridge Design,  including SM1600 and HLP (Heavy Load Platform) 320 and 400 loadings, as required.

With design and certification finalised, the team moved onto manufacturing. Once again, InQuik looked to partner with a local company. It was not long before leading manufacturer and supplier of steel reinforcing, Australian Reinforcing Company (ARC) got involved. According to David Hardy (Regional Manager NSW, ARC), “We’ve been associated with InQuik right from the outset. While InQuik had the design and IP, they needed to partner with a company that could do the manufacturing for them.”

It’s little wonder ARC and InQuik were such a good fit: the two companies share many of the same values. Classifying itself as a ‘true blue Australian company’, in 1920, ARC became the first to produce steel fabricated mesh in Australia at their Sunshine site near Melbourne.

Over the years, ARC has supplied the steel built into many of Australia’s most iconic structures, from the Sydney Harbour Bridge and Opera House, and the MCG and Marvel Stadium in Melbourne, through to Parliament House in Canberra.

“Today, all our steel products remain 100% Australian made with international quality assurance and in compliance with Australian Standards,” said David.

Prototyping and gaining traction
The team then moved onto testing. “We tested our initial ideas by installing a demonstration bridge on our family farm,” said Bruce. “This testing exercise was critical to the system’s success, as we ended up completely changing the self-supporting method. We had a tight timeline for the demonstration bridge, as we had planned an opening event where state and federal politicians would cut a ribbon. It snowed while we were pouring concrete two days before the opening.”

“Everyone who attended the event, including road authority engineers, highlighted that we had achieved something bigger than we realised, and this would change the future of bridge engineering. I didn’t think much of it at the time, but the more I refine and develop our system, the more I can see how different the system is to conventional bridge construction, and the advantages it has to its predecessors.”

The System first entered the Australian market in 2017. Since then, it has rapidly gained local market share as the product’s ease of installation and structural advantages are converting customers to using it as their preferred option for new and replacement bridges.

Logan explained how quickly the System has gained traction within the market. “Our first bridge sale was part of the Snowy Hyrdo 2.0 project—that was the first commercial bridge we ever completed. It only took 12 hours to build, including pouring all the concrete. In 2017, in our first year, we built three bridges. The year after, we built eight bridges. In last 12 to 18 months, we’ve built over 50 bridges.”

“It’s really been quite humbling to see how rapidly the System has been adopted and how revolutionary the market perceives the idea,” said Logan.

Increasing steel consumption
The InQuik System includes a variety of steel elements, from galvanised and zinc-alloy-coated steel, through to stainless steel and reinforcing bar. The steel consumption is approximately 70% pre-fabricated steel reinforcement, 25% coated steel product, and 5% stainless steel and ancillary steel elements.

The formwork is made from a coated steel product, which is left in lace for the life of the bridge. More conventional concrete construction uses temporary formwork, which is not typically made from steel and is reusable.

The use of permanent steel formwork increases steel consumption of the InQuik system by approximately 25% compared to conventional methods. Furthermore, in order to have sufficient steel for the structure to be selfsupporting, an additional 30% of reinforcing steel is required compared to conventional methods. Additional reinforcing is consumed for the integral InQuik bridge design and there are numerous stainless steel connectors, supports, and so on used in the concrete cover zone.

These steel elements mean the InQuik Bridge System consumes an additional 50% more steel compared to a conventional bridge of this type. Based on InQuik’s forecasts, in Australia, the system is likely to consume between 20,000 and 150,000 metric tonnes of steel, each year, over the next five years.

ARC has already seen an uptick in the demand for their reinforcing solutions. As David explained, “Our input has definitely increased as the InQuik product has become more well-known. To begin with, we were manufacturing the InQuik bridges from our Newcastle facility. Now, we make the bridges at both our Newcastle and our Brisbane facilities. This has improved our capacity, and gives us a more economical reach on the northern New South Wales and Queensland coast from a transportation perspective.”

 

Bridges destroyed by New South Wales bushfires replaced ‘InQuik’ time

Bridges destroyed by bushfire are being replaced in record time and at a fraction of the cost by local tradies and suppliers, thanks to InQuik’s world-first LEGO-like modular system. InQuik is currently helping local councils and workers to plan and construct 14 bridges in Clarence Valley, Eurobodalla, Oberon, Queanbeyan, and Shoalhaven, with more projects likely to follow.

According to Deputy Premier and Minister responsible for Disaster Recovery, John Barilaro, “Local contractors and council crews are trained up to assemble the bridges, which means councils can directly engage subbies, putting larger pay packets in their pockets with the added benefit of upskilling and delivering new business to local suppliers. One of ARC’s assembly teams finishes an InQuik Bridge System. The first InQuik Bridge delivered by ARC. Manufacture and assembly of an InQuik Bridge System.

Around 80% of the bridge is concrete, which is sourced from the region where the bridge is being built while transporting the modular sections to the site creates work for freight companies, and geotechnical studies and site-specific engineering are also completed by locals where possible.”

Barilaro said work to replace destroyed bridges was underway quickly, in one case within two days of an order being placed. “Work on two bridges that were on and near Armidale Road for Clarence Valley were fast-tracked thanks to Ballina and Hilltops councils, which asked InQuik to use the components already ordered for their own bridges to build the Clarence Valley bridge.”

Manufacture and assembly of an InQuik Bridge System.
Manufacture and assembly of an InQuik Bridge System.

“The InQuik Bridge System is a really good example of how Aussie companies can be successful when competing in the heavy manufacturing space. The InQuik System was invented, designed, engineered and manufactured, right here in Australia, using Australian steel. It demonstrates true innovation and shows that, even the most traditional materials and methods can be advanced,” said David.

The InQuik advantage
The benefits afforded by the InQuik System are considerable, from faster and simpler installation, and reduced maintenance, through to improved quality control and workplace safety. The globally patented InQuik Bridge System is a steel-reinforced, concrete bridge where the concrete cover is guaranteed in the factory and the concrete is fully poured onsite. It is lightweight to install and there is no propping required. For the bridge construction, the components are simply placed in position on-site and filled with concrete. This rapid construction time means a bridge can be installed in a matter of days. The short installation time using factory-produced, pre-engineered and certified components also offers a greatly reduced construction risk.

The deck panels include a reinforcing truss in the girders, which has thick cords at the top and bottom, connected by steel webbing. As the girder is placed between supports, and it takes the construction load of the concrete, this puts the bottom cords into tension for both dead loads and live loads, and the top cords are put into compression. The truss therefore takes the entire dead load of the structure and the concrete sets and remains in a neutral state until it has a live load. As the concrete dead load is entirely supported by the steel, this means the full compressive and tensile strength of the concrete is retained for live loads, leading to better performance. This considerably reduces the concrete crack width under dead loads and live loads, which increases the overall durability and life of the bridge.

According to Logan, “The big difference is that we use prefabricated formwork, and the steel is broken down into modular components. Those components are then transported to site and filled with concrete while in position. Some of the big benefits afforded by this process are reduced crane usage and manual handling. The ‘place and pour’ methodology means that an InQuik bridge can be installed in two to three days, over a total project timeline of one to two weeks.”

”Transportation is also easy. We can transport a whole bridge on one truck, reducing logistics considerably. One of our 12m units weighs about 5 tonnes. In comparison, if it was full of concrete, it would be closer to 35 tonnes.”

”In addition, the InQuik System creates a much better quality of bridge because it is one single mass of concrete. A lot of pre-cast bridges are comprised of smaller elements tied together—it is not one monolithic structure. As a result, our bridges require little to no required maintenance,” said Logan.

“The biggest differentiator with our system is that local, lowskilled people can construct the bridges. We’ve found that local councils are building our bridges with their own staff, or contracting them out to local residential builders or civil contractors,” said Logan.

The first InQuik Bridge delivered by ARC.
One of ARC’s assembly teams finishes an InQuik Bridge System.

Global opportunities
Bridges are an integral part of society and economic growth, and will always be needed. Throughout the world, there is an enormous volume of aging infrastructure. In the United States, there are some 600,000 bridges on public roads. According to InQuik, approximately 40% of these bridges are past their original 50-year design life and roughly 10% are classed as structurally deficient. The InQuik System addresses nearly 80% of the US bridge replacement market. It is estimated that the current backlog requires an investment of US$123 billion, and would consume approximately 1.2 million metric tonnes of steel if built using the InQuik System. Similarly, in Europe, InQuik estimates that there are approximately one million road bridges, with around 50% past their design life. This means that in the coming years, some 500,000 bridges will need to be replaced or upgraded.

The InQuik Bridge System is a globally patented technology. InQuik’s technology could enable governments, all across globe, to deliver large-scale construction programs, with local low-skilled labour, while keeping funds in the local community, and delivering long-term infrastructure cost-effectively. The scope and scale of the international markets means that many millions of tonnes of steel could be consumed every year in supplying InQuik bridges across the world.

InQuik is also investigating how to apply their technology to other markets. “At the moment, we’re focused on roadway bridges, but we also have designs for pedestrian crossings, rail crossings, as well as wharves and jetties. We’re looking at expanding into multi-storey high-rise buildings and a range of other sectors,” said Logan.

”We’re a true family-owned Australian business. The fact that we’re family owned plays a major role in how we run the business and treat our people. We’re definitely not about profits before people. It’s all about living the dream and enjoying the ride,” said Logan.

InQuik took out the 2019 T.C. Graham Prize, which is awarded by the Association for Iron and Steel Technology (AIST) to recognise innovative applications of iron and steel. The purpose of the contest is to encourage, generate and potentially incubate ideas that may lead to the development of new markets for steel.