サトウキビを使ったコンクリート!?

（以下、The University of East Londonから提供されたプレスキットのテキストの抄訳）

イースト・ロンドン大学は、テート＆ライル・シュガーズ社（Tate & Lyle Sugars）の支援を受けて、耕作副産物を利用して、既存の高炭素材料に代わる持続可能な超低炭素建築材料である〈シュガークリート（Sugarcrete）〉を開発した。

バガスと呼ばれる、砂糖の樹液を抽出した後に残るサトウキビの繊維を、独自に製作した砂やミネラル化合物と混合してつくられた〈シュガークリート〉は、建築におけるレンガやコンクリートを代替する可能性をもつマテリアルである。

また、グリムショー・アーキテクツ（Grimshaw Architects）との共同開発により、〈シュガークリート〉の最初の適用例である〈シュガークリートスラブ〉が発表され、プロトタイプが作成された。

©︎ Chromaphotography

〈シュガークリート〉が示すサステナビリティ

イースト・ロンドン大学のサステナビリティ研究所が行ったテストによると、〈シュガークリート〉の使用はコンクリート製造に比べ、最大28日間かかる硬化時間が1週間に短縮され、コンクリートブロックよりも4～5倍軽く、CO2排出量は15～20％であり、コストを大幅に削減できることが示された。

イースト・ロンドン大学の建築学講師であるアルモア・グティエレス・リバス（Armor Gutierrez Rivas）は次のように語る。

「サトウキビは世界最大の生産量を誇る作物である。世界中で年間約20億トンのサトウキビが生産され、副産物として6億トンのバガスが発生する。〈シュガークリート〉のようなバイオ廃棄物ベースの製品を使用し、従来のレンガ産業を代替することで、世界のCO2生産量の3％に相当する1兆800億トンのCO2を削減できる可能性がある。」

「建築環境は、世界の年間CO2排出量の40％を生み出している。地球温暖化を1.5℃に抑えるという世界的な目標にもかかわらず、2060年までに世界の建築物の床面積は2倍になると推定されているのが現状である。したがって、現在の建設方法に代わるものを開発する必要があるのである。」

©︎ Chromaphotography

新築・改修に活用できる床システム〈シュガークリートスラブ〉

研究プログラムの一環として、シュガークリートを活用した床スラブのプロトタイプを開発し、高度なデジタルモデリングとロボットによる製作を使用して、建設における超低炭素材料の実現可能性を検証した。

グリムショー・アーキテクツが以前行ったインターロッキングジオメトリー（建築部材の形状を利用して自立した組立体をつくること）の研究により、〈シュガークリート〉は、新規または既存の構造物に適用、分解、拡張できる、取り外し可能で再利用可能な耐火複合床スラブとして展開することが可能となった。

このプロジェクトの一環として、テート＆ライル・シュガーズ社との協力のもと、チームは砂糖の主な生産地である南半球で、〈シュガークリート〉を採用する機会のある場所の特定を開始した。現地のNGOと協力して、プロトタイプをテストする予定である。

また、この研究の次のステップとして、〈シュガークリート〉だけでなく、多様な作物や地域から得られる副産物を活用したバイオクリートを世界的に展開する可能性を示すためのデジタルツールの開発と共同設計を行う予定である。

以下、The University of East Londonのリリース（英文）です。

The University of East London reveals SugarcreteTM a low cost, low carbon construction material upcycling sugarcane by-products.

The University of East London’s (UEL) Master of Architecture and Sustainability Research Institute (SRI) with the support of Tate & Lyle Sugars has developed an innovative construction material – SugarcreteTM – which, using arable by-products, provides a sustainable, ultra-low carbon construction alternative to existing high carbon materials. In creative partnership with Grimshaw the first technical application of SugarcreteTM – SugarcreteTM Slab has been announcedprototyped.

Created by mixing the sugarcane fibres left over after sugar sap extraction, known as bagasse, with bespoke sand-mineral binders, SugarcreteTM is a material which has the potential to be used and re-used in new or existing structures, replacing both brick and concrete.
Developed over two xxxx months/years, testing of the material by UEL’s SRI showed that using SugarcreteTM, when compared to concrete production, reduces curing time to one week (a process that takes up to 28-days), is four to five times lighter than concrete block, only uses 15 – 20 per cent of its carbon footprint and provides substantially reduced costs.
Armor Gutierrez Rivas, Senior Lecturer in Architecture at UEL, said: “Sugarcane is the world’s largest crop by production volume – almost two billion tonnes of sugarcane are produced worldwide yearly, resulting in six hundred million tonnes of fibre bagasse as by-product. Using a bio-waste-based product like SugarcreteTM, we could replace the traditional brick industry, offering potential saving of 1,08 billion tonnes of CO2, 3 per cent of the global CO2 production. The built environment generates 40 per cent of annual global CO2 emissions. Despite the global aim to hold global warning to 1.5 degrees Celsius, it is estimated that our global built floor areas will double by 2060. Therefore, we must develop alternatives to current construction methods.”
As part of the research programme UEL developed a prototype floor-slab made from sugarcane derived from SugarcreteTM and used advanced digital modelling and robotic fabrication to test the viability of the ultra-low carbon materials in construction. Grimshaw’s previous research into interlocking geometries – using the form of the building components to create self-supporting assemblies – allowed SugarcreteTM to be deployed as a demountable, reusable, fire resistant composite floor slab which can be applied, disassembled, or extended in new or existing structures.
“SugarcreteTM when integrated as a floor slab adapts Abeille’s 1699 design for dry assembly flat vaults – the system is made of interlocking components which transfer loads across the slab between blocks, restrained using post-tensioned perimeter ties, reducing the steel content of the slab up to 90 per cent.” said Elena Shivlova, architect at Grimshaw. “Reducing steel, combined with the use of sugar cane fibres of different densities in a modular system allows the slab assembly to avoid the potential risks of cracking which occur with traditional concrete in extreme situations, absorbing the effects of seismic shock – a characteristic vital in earthquake prone regions where sugar cane is cultivated.”
As part of the project, and working with Tate & Lyle Sugars, the team has started to identify sites in the sugar producing Global South, which have the opportunity to adopt SugarcreteTM. The intention is to work with local NGO’s to test a prototype.
Alan Chandler, Co-Director of the UEL’s SRI, said: “By partnering locally, the production potential in each situation is evaluated, defining whether cement-use reduction can be made using locally created SugarcreteTM, or whether there is capacity to grow export markets for raw material or finished products to benefit GDP. This is particularly relevant for sugar producing communities where construction materials are frequently imported, environmentally poor performing, high cost and high carbon – for example a concrete block in Cuba, a major sugar producing country costs $3 – an average monthly salary is $148.”
SugarcreteTM has been nominated for this year’s Earthshot Prize by former winners, Notpla, in the Build a Waste-Free World category. In addition, researchers from UEL will publish their first set of SugarcreteTM journal papers with its partners over the coming year, alongside carrying out further research on structural, durability and acoustic properties of the constituent materials.
More information is available via the University of East London SugarcreteTM webpage.

Notes to editors:
The SugarcreteTM research has been published and not patented; this decision purposefully shares knowledge to generate possibilities locally for producers to use its simplicity to reduce cement as much as for developing digital solutions using advanced geometry.
The next steps of the research will see the development and co-design of digital tools linked to by-products availability from diverse crops and regions and performance criteria that maps the potential to deploy SugarcreteTM and other bio-crete formulations globally.
Link to images.
Link to SugarcreteTM video.

Team
Material Concept, Design and Fabrication:
Armor Gutierrez Rivas, Senior Lecturer in Architecture, UEL
Alan Chandler, Co-Director Sustainability Research Institute, UEL
Bamdad Ayati, Sustainability Research Institute Research Fellow, UEL
Elena Shilova, Architect, Grimshaw
Andy Watts, Director of Design Technology, Grimshaw

Collaborators:
John Kerr – Vice President, Research & Technology, Tate & Lyle Sugars
Paris Nikitidis – XR Developer, Grimshaw
Philip Singer – Computational Design Specialist, Grimshaw
Georgios Tsakiridis – Consultant, Grimshaw
Paolo Vimercati – Consultant, Grimshaw
Robert Sims – Model shop Manager, Grimshaw
Paul Nichols – FabLab Manager, UEL
Dr David Tann – Dean of School of Architecture, Computing & Engineering, UEL
Carl Callaghan – Head of Department of Architecture and Visual Arts, UEL
Alex Scott-Whilby – Architecture & Physical Design Cluster Lead, UEL
Nicolo Bencini – Senior Structural Engineer, AKTII
Sky Henley – Computational Design Specialist

UEL Master of Architecture Students Team:
Faith Omowunmi Ogundare; Busra Ciftci; Amy Gillespie; Hinal Arvindkumar Patel; Rova Taha; Dodangodagamage Kawan Roger Ranasinghe; Manoj Sai Ganji; Mohan Ukabhai Dungrani; Anca-Madalina Borda; Alina Klimenteva; Rashmi Madagamage Gunathilaka; Orseer Isreal Gbashah; Mahmoud Sayed Abdellattif; Mert Manas Erten; Hidayati Yazmin Binti Abdul Halim; Oluchukwu Judith Obiejesi; Svetoslav Georgie Slav; Mihriban Ustun

Photography:
Chromaphotography

Videography:
Jude Adoasi

Editing & filming:
Louis Bird and Ellie Saunders, Grimshaw

About Grimshaw
Grimshaw is an international architectural practice delivering buildings, infrastructure and places that are underpinned by the principles of humane, enduring, sustainable design. With offices in London, New York, Los Angeles, Paris, Dubai, Melbourne and Sydney, Grimshaw employs over 550 staff. The practice’s international portfolio covers all major sectors and has been honoured with over 200 international design awards.
https://grimshaw.global

「SUGARCRETE」The University of East London 公式サイト

https://uel.ac.uk/sugarcrete-slab