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.”