The Wood Technology Society (WTS) reinforced the message that wood science is alive and kicking in a two part online conference held over the afternoons of September 9 and 10.
As might be expected from the WTS and its umbrella organisation, the Institute of Materials, Minerals & Mining (IOM3), the conference was highly organised, with prerecorded video presentations and papers available before and after the event, allowing plenty of time to absorb the information.
The live element consisted of three-minute ‘pitches’ by each of the speakers, highlighting the main points of their presentations, and question and answer sessions. The organisers also built in virtual coffee breaks and a social event, enabling participants to chat online.
“We were very pleased with the event, and especially the way the presenters adapted to the online world, learning new skills in compiling their video presentations,” said Morwenna Spear, research scientist at the BioComposites Centre, Bangor University.
“The comments back from delegates have also been very positive, so the format appears to have worked well,” continued Dr Spear. “We aimed to strike a balance between creating an online community for discussions and questions, as well as flexibility for delegates to watch presentations at their own pace. Registrations were increased by the move online and technical content remained high, with a wide range of topics covered and some very inspiring speakers.”
Graham Ormondroyd, head of materials at Bangor University and chair of the WTS was equally happy with the online platform.
“Whilst it is always a shame not to meet with friends and colleagues to discuss new innovation in the timber industry, the current climate forced us to go online, pushing out a novel approach to delivering the conference,” he said. “Using pre-recorded presentations and live Q&A sessions seemed to be engaging, whilst not forcing the attendee to sit in front of a computer for endless hours. The format seems to have worked well and was delivered to the approval of the audience.
“Online has become a norm out of necessity, however I do think that online events are here to stay and we should be developing more virtual content for our members, whether this is larger conferences like Timber 2020, one-hour seminars or vlogs, the challenge is to find our unique selling point in a sea of online content.”
The conference was split into sections under the headings structures; visualisation, sensing and modelling; education; properties of wood, bamboo and composites; applications and future challenges; wood modification; and the circular economy and resource efficiency.
After a welcome from Martin Ansell, associate professor at the University of Bath, who looked at massive timber structures through the ages, from 8th century Japanese temples to Mjøstårnet in 2019, Alicja Przystup, a PhD student at the University of Edinburgh, presented her research on cross-laminated timber (CLT) connection behaviour under extreme deformations and its influence on structural robustness in large timber construction.
Her study looks at the ability of a CLT building to resist local damage and to prevent progressive collapse focuses on developing a localised component test methodology of high repeatability that isolates the behaviour of individual elements and connections, and investigates their influence on the robustness of the structure as a whole. Experiments have been taking place on two key components of a CLT building – a continuous 5-ply CLT section, and a half-lap floor joint.
David Trujillo, assistant professor at Coventry University’s school of energy, construction and environment gave an insight into his specialist subject – bamboo. Prof Trujillo led the development of two ISO standards for bamboo, which are now British Standards (BS ISO 22157 and BS ISO 19624 and he is actively participating in the revision of ISO 22156 (structural design) and chapter G of Columbia’s building code (Columbia is the one of the major builders of bamboo structures in the world).
He said that many of the standards had been “borrowed” from timber standards. George Fereday, associate teaching professor at London Metropolitan University’s School of Art, Architecture & Design, outlined early experiments made with the “XR Beam”, a trussed hardwood beam that may offer value added uses for small diameter coppiced roundwood. This is commonly extracted as part of woodland management in the southeast of England and the aim is to stimulate and expand new market potential for this under-used resource within the domestic construction industry.
The beam is designed to be produced with as few manufacturing processes as possible to reduce cost and waste and to retain the natural strength of the timber as the tree has grown it.
Visualisation, sensing and modelling was covered by Tim Belden, a postgraduate researcher at the University of Surrey; Kyle Carter, a masters student at the University of Wales, Trinity Saint David; and Frits Van Calker, managing director of RFIdirect Ltd.
Tim Belden’s presentation looked at the use of computer vision techniques as a straightforward method to convert images of microtome slices into a 3D computer package that can be imported into most CAD packages.
Kyle Carter is currently completing his dissertation project alongside Lignia Wood Company, focusing on material handling practices and lean manufacturing. In his presentation he explained how his study aimed to improve lead times and identify and reduce waste in the production of modified wood.
He concluded that, in common with many timber production operations, material handling created the most waste within Lignia manufacture and he said the biggest potential for reducing waste was to look at the different elements of handling using 3D modelling. Frits Van Calker addressed the embedding of RFID in a production environment, making the business case for data capture in the production line and introducing Industry 4.0 principles.
The project he demonstrated to Timber 2020 delegates was the first phase in creating full traceability of fire doors and frames through the production line and thereafter in the delivery and annual inspection of them.
Three speakers covered education – Joseph Little, assistant head of school at the Dublin School of Architecture, Technological University (TU) Dublin; Robert Wolverson, research engineer at Swansea University and Lignia Wood Company; and Tabitha Binding, university engagement manager at the Timber Trade Federation (TTF) and TRADA.
Mr Little explained the rationale behind the creation of the TU’s new BSc (Hons) in Sustainable Timber Technology, which included dovetailing with the United Nation’s Sustainability Development Goals (SDGs), and capitalising on the 2016 prediction that Ireland’s roundwood production was set to double within 15 years. It also tied in, he said, with Brexit raising the possibility of diminished access to the valuable UK export market.
Robert Wolverson discussed the circular economy of composite wood and comparison to current wood modifications.
His engineering doctorate (EngD) challenge is to find a suitable fire retardant that doesn’t hinder the enhanced properties of Lignia afforded by its production process – and to balance that with finding a way to recycle the product.
A quick tour of TRADA and the TTF’s online resources and current projects was presented by Tabitha Binding, who reminded delegates that educating design lecturers and their students on timber products was vital if the construction industry is to reduce its 40% share of greenhouse gas emissions per year.
The second day’s online event saw Dominika Malkowska, of Bristol University; Janet Sycamore of the Timber Decking & Cladding Association (TDCA); Jerry Quayle, of Jerry Quayle and Associates; and Dan Ridley-Ellis, of Edinburgh Napier University looking at the properties of wood, bamboo and composites.
PhD candidate Dominika Malkowska presented her research on the connections in natural, round bamboo – specifically on predicting the splitting capacity of dowelled connections in bamboo – and was followed by Janet Sycamore, who described the TDCA’s work in developing an approval scheme for wood-plastic composite (WPC).
Ms Sycamore said that the market for WPC decking had grown but that the product was far from generic, with different materials and manufacturing processes resulting in different end products. The quality of some of these had been lacking, she said, and this had the potential to damage the reputation of the whole timber decking sector.
The Product Approval Scheme (PAS) for wood fibre based, wood polymer deck boards features nine testing requirements (seven mandatory, two optional) based on standard BS EN 15534-4: Composites made from cellulose-based materials and thermoplastics.
Specifications for decking profiles and tiles. “Don’t blame timber because it burns” was the title of Jerry Quayle’s presentation, and he asked why the construction and timber industries don’t focus their collective might on the future of timber by seeking to improve its performance in a fire by developing fire retardant impregnation systems.
He said that the research he sees is based on how to curtail fire instances and how to protect timber by covering it up. Conversely, there is little R&D on timber treatments to slow charring, the key element in the fight for fire resistance.
“If the timber industry wants to sell timber in areas where fire is a risk and not have the finger of doom pointed at them, they need to sort themselves out,” he said.
If Mr Quayle posed some thorny questions, Dan Ridley-Ellis brought up even more with his presentation “Some awkward questions about density”. He is working on a project on the circular economy and re-using timber and said that the density of structure is key to this.
“There are several different concepts of wood density, such as specific gravity, basic density, dry density and even oven dry density,” he said. “These are often confusing and sometimes poorly described in the literature, but they can be unambiguously defined and measured in simple and repeatable ways. This makes density a popular measurement in wood science and timber processing, but also leads to a general over-estimation of how well we can actually know the density of a particular wood resource, especially when it is reported with a spuriously high level of precision.”
The subjects of applications and future challenges were addressed in the next session, with Simon Curling, project officer at the BioComposites Centre, Bangor University, updating delegates on the potential effects of climate change on the durability of timber.
The predicted warmer, wetter winters and warmer, dryer summers, he said, would create the perfect climate for timber to decay in and he advocated protection methods such as good building design and maintenance, preservative treatment and modification. Simon Curling, professor of marine zoology at the University of Portsmouth, followed this with a presentation on marine borers, which could destroy large wooden piles in tropical waters in a matter of months. Shipworms can grow up to half a metre long and “do a lot of damage”, he said.
He went on to say that there is an increasing intensity of shoreline development around the world and that “people will expect long service life of timber”.
However, traditional wood treatments using biocides were being limited by perceived environmental issues so there is a need for alternatives. He said this had led to the increasing use of modified timber in marine applications.
“There is an opportunity for innovation,” he said and concluded that to enable innovation, testing of efficacy needs to provide rapid and reproducible results and standard testing methods need to incorporate laboratory testing into a suite of lab, marine and service trial evaluations.
The next session – wood modification – saw presentations from Carlo Kupfernagel, a PhD student at Bangor University; Morwenna Spear; and Bronia Stefanowski, research and technical manager at Lignia Wood Company. Carlo Kupfernagel has a particular interest in the impregnation of solid wood with PF resin and his presentation focused on the effects of fatigue cycling on acetylated, thermally treated and PF-modified Scots pine.
With the increasing uptake of modified timbers and new applications being found for it, it was likely that some of these applications would see modified wood being exposed to a dynamic loading situation and hence experiencing material fatigue, he said.
End-grain cobbles were a well-known flooring, paving and road surfacing product in the 19th century and saw a resurgence of interest this century thanks to Coed Cymru’s Endgrain project, which sought to find applications for Welsh-grown timber.
Dr Spear reported on work undertaken for the project between 2009-2015 to consider resin treatment as a method of enhancing the durability and wear resistance of Welshgrown Scots pine and beech for flooring and paving applications. The project found that PF resin modification was simple and effective and that the treatment was most successful with Scots pine.
The modification process undergone by Lignia was outlined by Dr Stefanowski, who also presented a review of the literature relating to PF and PUF modification of wood and its effects on wood properties.
The final session of the day – circular economy and resource efficiency – saw Callum Hill, director at JCH Industrial Ecology Ltd explore the various aspects that need to be taken into consideration when modelling timber cascades from a lifecycle assessment (LCA) perspective.
He was followed by Graham Ormondroyd, who looked in more depth at LCA and at the current practices within the timber industry around the protection of society and societal needs, comparing them with the emerging role of social LCA and its potential to influence the industry’s decision making.
Marlene Cramer, a research assistant at Edinburgh Napier University’s Centre for Wood Science and Technology provided a perspective of the wood recycling industry in the UK, including community wood recyclers, chip producers and panel manufacturers, and gave an insight on how it could become even more circular.
