Three engineers, Peter Bruechle, Ernie Evans and Norm Gilchrist, joined forces in 1970, to establish a company that has grown to be a practice now employing more than 200 staff, in five Australian and two international offices. In the forty years since BG&E commenced our journey, we have grown to be a strong, respected team of Consulting Engineers, who specialise in analysis, design and documentation of:

	Building Structures		Civil engineering
	Facades		Marine structures
	Bridgeworks		Water engineering
	Infrastructure		Building Information Modelling (BIM)
	Environmentally Sustainable Design		Support Services

BG&E recently welcomed 180 distinguished guests to join in celebration, marking our 40th year of innovation and outstanding engineering excellence. Gathering in the imposing foyer of Central Park, Perth CBD, our valued clients and associates enjoyed an evening of networking and celebration. We thank you for making the evening a success. Photos can be found here.

40 year celebrations will continue in Sydney and Brisbane over the next few months.

We received excellent feedback regarding the evening. From all accounts, it seemed attendees enjoyed the opportunity to network and relax with colleagues and clients. The team worked hard behind the scenes to create the evening and we are appreciative of the feedback we received. A few comments are paraphrased below.

Lou Cotter, Director, the Buchan Group— ‘Chris and I would like to thank you for the opportunity to celebrate the 40+ years of successful operation and growth of your Engineering practice with you and your team last night. It was a very good turnout, which is testament to your loyal client base!’

Ian Smith, Principal, Golder Associates Pty Ltd— ‘Congratulations on your 40th and thank you for a great night. You must be very proud of what you have achieved and your strong foundation for further success. The attendance last night was a testament to the esteem in which BG&E is held in Perth. I felt honoured to be invited and appreciated the opportunity to catch up with so many friends at BG&E and in the industry. We recognise that being able to work with BG&E over the years has been a major contributor to our success in WA. Best wishes for the future.’

Andrew Bland, Business Development Manager, Georgiou— ‘Thank you for an entertaining evening last night, it was good to mingle with construction industry friends…it was good to catch up with members of the BG&E team. I know how difficult it is to organise and coordinate these events and everything appeared to go like clockwork. I think John Flecker’s summary of the 40 year history of BG&E as “Bloody Good Engineering” hit the nail on the head – we look forward to the next 40 years! Once again thank you for a great evening and the anniversary book.’

BG&E designs concrete LNG storage tanks, a task that requires sophisticated finite element analysis and the consideration of unusual and extreme scenarios. LNG storage tanks are designed to international standards and require multiple levels of redundancy to maximise safety.

While not a new concept, ‘Membrane Containment’ type systems are just beginning to develop popularity for the above ground storage of LNG.

Modern membrane systems originated from the containment systems used in large LNG carriers. They consist of a thin, flexible, stainless steel ‘primary’ membrane supported by thermal insulation panels. These insulation panels are, in turn, attached to a load bearing and vapour tight support. In this case, a large, concrete outer tank with an applied, polymeric vapour barrier provides this support, carrying the product load.

In a membrane containment system, the functions of product containment, insulation and structural support are separated in the most efficient way.

While the mechanical components and the membrane system are typically proprietary components supplied by a membrane supplier, the outer concrete tank is adapted specifically for each project. Opportunities arise by considering the client's design criteria, the contractor's preferred construction methodology and specific site conditions.

The outer concrete tank consists of a post-tensioned concrete wall, which is supported by and monolithically connected to, a reinforced concrete base slab with thickened edges. Typically, a reinforced concrete dome roof is also provided, cast over a steel membrane plate. The roof is required to take the weight of the pump wells (which are hung from the roof), as well as provide support for external platforms, pipework and a suspended deck inside the tank.

Design of the outer concrete tank is complicated by its shape and monolithic nature, as well as various construction stages such as the roof construction, provision of temporary openings and hydrotesting. One of the critical loading scenarios is the accidental/abnormal case of leakage of the primary containment. For this design scenario, it is considered that the LNG has bypassed the primary membrane and acts directly on the tank wall (or secondary barrier, where present), creating significant, thermally induced stresses and changes in material properties with cryogenic temperatures. BG&E overcomes such design challenges, using sophisticated modelling and analysis procedures.

The weight of more than 80,000 tonnes of stored LNG is significant, so it is critical that the foundation is able to resist the load. Different foundation options are possible - such as piled foundations or spread foundations - with or without various soil improvement techniques.

See Figure 1 below for a more detailed explanation of the components of a ‘Membrane Containment’ type tank.

Typical membrane type LNG storage tank (courtesy of GTT)

BG&E has been designing a ‘Membrane Containment’ type LNG tank for Laing O’Rourke as part of the LNG Limited Fisherman’s Landing project in Gladstone, Queensland. The proposed, above ground tank has a net capacity of 180,000m³ and has a monolithic, reinforced concrete roof. LNG Limited together with Laing O’Rourke evaluated various tank designs specifically for the Australian industry and selected the membrane tank due to its advantages of shorter construction durations and reduced costs.

LNG Limited’s core objective for this project is to commence first LNG production in 2014. If that timeframe is achieved, the Gladstone LNG tank will be the first membrane type LNG tank in Australia.

What is it? Building information modelling (BIM) is a design method whereby software is utilised to generate complex, 3D representations which contain intelligent information about the building components. This is useful to all parties involved throughout the life of the building, including designers, quantity surveyors, builders, clients and facilities managers.

Model element attributes and other material properties embedded in the structural models, can be effectively coordinated and integrated with architectural and building services models.

BG&E is proficient in the use of Building Information Modelling within the Structural engineering industry.

Consider the use of BIM for your design projects: see 'How to get started' on our BIM page for more information about when BIM is applicable.

BG&E are utilising other 3 dimensional modelling software with Tekla Structures for structural documentation and fabrication shop drawings.

BG&E utilises a number of CAD software packages across the business. In 2008, we adopted Autodesk® Revit® Structure to complement our existing modelling and drafting capabilities and also soon after commenced utilisation of Tekla Structures. We have used a gradual integration of Revit modelling and documentation into our project delivery.

The majority of all our building documentation across BG&E in the past 3 years, has been prepared using Revit. We apply it in particular where required by the client and where we consider that modelling would expedite and enhance the delivery and construction process. For several of these projects, BG&E have been the only member of the design team using Revit modelling.

Fiona Stanley Hospital, Central Energy Plant, Perth, WA

BG&E have documented over 100 projects using Revit® Structure. Many of these included Design and Construct of multiple buildings. An example is the Fiona Stanley Hospital, where we modelled 5 buildings and a buried service tunnel using Revit® Structure. Currently, BG&E is providing the structural engineering modelling for hospital, residential, commercial, civic building projects as well as for civil coordination. For some of these projects, like the QEII Central Energy Plant buildings the project design team is responsible for delivering level 6D models.

The Curtin University Engineering Pavilion was designed with a 5 ‘Green Star’ rating in mind.

BG&E researched a number of cutting edge material technologies for use in the structure of the building, as part of this drive to obtain a 5 star rating.

The building design was chosen to explicitly show its engineering aspects. A steel diagrid structure has been chosen as part of this expressive concept. This shares the wind loads on the triple height atrium glazing across multiple members and acts as the primary stability bracing system for the building. Combining the atrium wall support system with the bracing system in this way has removed some structural shear wall elements from the design.

The diagrid that wraps around three sides of the atrium at the west end of the building, is a fully welded, exoskeletal frame, fabricated from 300 x 200mm, rectangular hollow sections. These were prefabricated in the shop into sections of both the cladding and frame, up to 20 x 6m in size. These giant assemblies were then manoeuvred onto site, erected using a 200t crane and site welded together in position with a prepped site butt weld, to give a continuous diagrid look.

Reuse Recycle Reduce

A triple height atrium provides connectivity to the three floors of the building, containing walkways and vertical circulation. One of the walkways was an existing, 1970s concrete link at first floor level. This previously joined the buildings either side of the site. A collaborative and extensive design effort between the architect, Taylor Robinson and BG&E, meant that this walkway was incorporated into the new atrium, reducing demolition and new build requirements.

The floor slabs are post-tensioned to reduce the volume of concrete used and maximise space for services in the ceiling, without the need to increase the building height, which would have added to the material use in facades and walls. This additional services space safeguards the building for the future demands and changes of the university.

Cement Substitutes

All concrete across the project contains Portland cement replacement materials in the concrete mix design. The replacement product used was ground granulated blast furnace slag (GGBS), which comes from the steel making industry as a by-product. Every tonne of Portland cement produced, represents one tonne of CO2 released into the atmosphere, so using a by-product instead of manufactured cement is beneficial to the environment. Typically, a minimum of 15-30% replacement was used in mixes, depending on the type of element.

The Roof Solution

The solution for the support of the roof structure across the 19 x 17m exhibition space was to use three, bow string trusses supporting timber purlins. The bow string trusses are comprised of two, 115 x 460mm glulam timber beams, either side of a 6mm thick, steel flitch plate as the top chord of the truss and a 25mm diameter, tensioned stainless steel rod as the bow string bottom chord. Combining the materials kept the use of steel to a minimum, without the need for excessively large timber members. All timber was specified as being Forest Stewardship Council certified.

BG&E is known for its ability to create innovative solutions that increase the green rating for structures. For more information about our capabilities in Sustainability, visit our website page here.