A Load Take-Down is a procedure frequently performed by structural engineers to assess the amount of loading carried by the columns of a building into its foundations. It is an important early-stage analysis necessary to inform the choice of column layout and foundation system, but it is also a notoriously tedious and time-consuming process that is regarded as something of a ‘rite of passage’ for young engineers to endure.
Typically, the take-down is performed in one of two ways. Either the tributary areas (the region of loading that each column nominally supports) must be calculated manually for each column on each floor and then tallied up (commonly via a spreadsheet), or a full 3D finite element model of the entire building must be constructed and the forces extracted. The latter requires resolution of a level of detail which is often inappropriate during the early phases of a project and the former is both slow and prone to errors. Most importantly, both methods can require significant re-work in order to adapt the analysis to modifications of the geometry and this limits our ability to experiment and respond to design changes.
RCD’s TADPOLE (TAke-Down Process On Loaded Elements) is an in-house software project that provides a new alternative method that automates and greatly speeds up the analysis. The standalone tool can read in 2D floor plan drawings and assemble them, level by level, into a complete representation of the building. Loading areas and column positions can be automatically interpreted by the tool if present, otherwise the software contains a full suite of drawing tools to allow the engineer to sketch out loads, columns, walls etc. Once this data has been input the software automatically determines tributary areas and performs the take-down. Changes to the input data can be made easily and the impacts assessed instantly.
This eliminates the need for tedious manual calculation and, because the application is designed and streamlined for this specific purpose, there is no need for any extraneous data to be input. Because the tool is graphical, odd results and input errors can be spotted and traced far more easily than in a spreadsheet.
To help further manage the data the results of the analysis can be output to an interactive online dashboard via Power BI, making it easy for the lead engineer and client to interrogate. A full report can also be generated to document the process, results and assumptions. To eliminate re-work, the tool can also assemble the input plans into a full 3D building model that can be exported to Autodesk Robot to form the basis of a more detailed analysis.
This has allowed us to do in hours what would previously have taken days, and in a way that would not have been possible without building the tool ourselves. Commercial software is typically made to be as broad as possible in order to capture a wide user base. This means that it is often poorly optimised for certain tasks. By developing our own tools designed to meet our exact requirements and workflow we can plug these gaps and work more efficiently, enabling us to beat time pressures by responding faster, iterating more often and, ultimately, to produce better, more rigorously-checked designs.
The 2014 EcoBuild exhibition at London’s Excel centre opened this week and an egg-shaped plywood pavilion designed for OnGreening’s stand at the event is showcasing the work of Ramboll Computational Design (RCD).
OnGreening is a new web-based platform devoted to the research and profiling of green building technologies. The organisation required a pavilion and lecture theatre that would make them stand out from the crowd at the world’s largest event for sustainable design at the ExCel centre in London.
The look of the structure is intended to echo Ongreening’s goal of capturing and filtering the world’s knowledge of green data. The pavilion has already attracted a lot of attention.
The pavilion’s egg-like geometry was generated using form-finding techniques pioneered on previous RCD projects. The structure itself is unique in that it uses thin 6.5mm birch plywood timber laths which are bent into shape, creating a so-called ‘bending active’ structure which is incredibly stiff and acts like a monocoque, enabling the shell to carry most of the stresses.
The timber laths are aligned along geodesic lines between pre-seeded generation points set out using a parametric model. The primary geodesic members are restrained by secondary laths of the same narrow and thin profile of plywood with a simple bolted connection. This method allowed the use of straight and short length pieces of timber, making it more practical to purchase and build compared with other similar looking structures.
Further details about OnGreening and their work are available on their website.
RCD have collaborated with the staff and students of the Architecture and Fine Arts departments at Oxford Brookes University on a striking new urban intervention/sculptural pavilion at the entrance of the new Abercrombie building. The structure compromises 20 extremely tall and slender steel ‘trees’ that support a thin folded steel plate ‘leaf’ or canopy. The overall impression is that of a wooded glade where light is filtered through varying diameter circular voids in the canopies and the stems bathing the visitors to the installation in a dappled light. RCD were an integral part of the conceptual design process following the initial student competition.
The extreme slenderness of the stems (only 89mm diameter and 6000mm tall) required extensive input from Ramboll’s fluid dynamics team in Copenhagen and fatigue analysis by our Advanced Engineering team in Southampton to model the complex wind interactions in order to prevent dynamic failure and to keep the structure as slim as possible. The canopies are 2500mm at their widest but only need very thin steel plate (2mm) because of the inherent stiffness provided by folds and creases in the form.
We developed routines to allow the circular voids to intelligently self organize on the surface of the stems and canopies in relation to the level of stress. High stress in a particular area meant that voids were fewer in number. Dampening factors were built into the initial coding to ensure that the overall impression of the holes was a gradual fading rather than unsightly bunching. The work will be extended to include our work on integrating a lightweight finite element solver within the automatic void generation and movement process in order to give more control and instant feedback on structural performance. A technical paper will be presented at a future paper conference.
Ramboll Computational Design (RCD) has been selected to design modular toilet buildings for schools throughout India.
The client is a joint venture between a UK-based investor who specialises in funding female entrepreneurs throughout the developing world and NVH Technology, an award-winning entrepreneurial provider of sanitation services in India.
The client plans to expand their range of commercial products into toilet facilities for schools, and has appointed Ramboll to provide design services. The client approached Ramboll Computational Design after seeing RCD’s presentation on the Trada Pavilion, given at the Ecobuild exhibition in London’s Excel Centre earlier this year.
This is an exciting project for Ramboll as it broadens our product design expertise and capabilities in design for mass manufacture. It also provides an opportunity to create a significant beneficial impact on improved sanitation and achieving universal education through improving the standard of school facilities. The United Nations estimates that up to 2.5 billion people worldwide lack access to basic sanitation and reforming this situation is a United Nation’s Millennium Development Goal.
As a commercial venture, Ramboll have worked with the client to develop a unique fee structure which is partially based on royalties gained through the licensing of Ramboll’s intellectual property. Additionally, a custom scope for product design work was prepared and tailored to the client’s particular brief.
The Rambøll Computational Design (RCD) team were invited to help design a number of installations at the world-famous Burning Man Festival in Nevada, USA this year by Westminster University School of Architecture.
Burning Man is an annual event held in the Black Rock Desert in northern Nevada. It takes place annually beginning on the last Monday in August, and ending on the first Monday in September to coincide with the Labor Day national holiday. The event takes its name from the ritual burning of a large wooden effigy on the Saturday evening and is described as an experiment in community, art, radical self-expression and radical self-reliance.
The week-long gathering of counter culture takes place in August, giving the team a very tight programme in which to design three climbable sculptures, two recursive ‘fractal’ forms, and a double curved and cantilevering timber shelter, and then help organise their digital fabrication.
In recognition of RCD’s recent experience of collaborative digital modelling of unusual forms, combined with the hands-on production of the Belvedere festival sculpture in New York and Trada Pavilion in the UK, our team were invited by tutors at the Westminster University School of Architecture to assist the student team that won the international design competition earlier this year.
Ramboll Computational Design have conceived and created a weave shell structure from strips of Perspex to transform the foyer of our London studio. The unique doubly-curved triaxial mesh shell installation explores how engineering, digital fabrication, and imagination can fill the boundaries of the space. It inherits the tradition of innovation and material exploration from our 2011 Foyer 1.0 timber principal curvature shell but extends the automatic form finding and associative modelling in new directions. The form has been generated using our self coded dynamic relaxation techniques and the cutting patterns for the flat perspex elements are automatically generated from the Grasshopper model.
The structure will built by early September in time to feature in the London Design Festival 2013.
Ramboll engineers have conceived the Fitzrovia Chalkboard for the Great Titchfield Street Festival as part of London Festival of Architecture 2013. One of a number of events planned for the month long festival, the inaugural street project will promote positive change in the area, transforming Great Titchfield Street – from Mortimer Street up to Langham and Foley Street – into a pedestrianised haven for the day.
Fitzrovia Chalkboard is a temporary installation that creates a single point of display for collective messages in the local community – a structure that is a massive writing surface for all to contribute. It is inspired by how local, independent businesses rely on the traditional chalkboard as a means to advertise and mark their place on the street, in a time when technology offers many alternatives. Fitzrovia Chalkboard is designed using such recent advances and the public are invited inside the structure to view its innovative construction.
Inspired by Ramboll’s recent Trada Pavillion, the structure comprises of 47 birch plywood panels joined together by steel hinges. It is designed using the Tangent Plane Intersection (TPI) methods developed by Ramboll Computational Design to break down any double curved form into flat planar elements. Exact cutting patterns for digital fabrication are then automatically generated from the TPI mesh. All panels are numbered sequentially and this approach ensures that all panels fit together to create the form in a quick assembly process.
RCD collaborated with Architects and light installation artists Cinemod on the design for the RIBA organised Radio 4 Listening Pod competition, a brief to create a portable and memorable looking recording studio.
Christened the Geode, the pod was inspired by natural mineral formation and by the TPI mesh surface techniques developed by us on the Trada Pavilion. The TPI mesh enabled the structure to be broken down into small, light and easily transportable plywood and acoustic foam components which could then be slotted together on site by hand. Our entry was not shortlisted but did us give a valuable opportunity to develop the planar intersection modelling techniques further, to build on our knowledge of digital fabrication and to explore new ideas with creative partners.
Working with Architects Innovation Imperative, Ramboll Computation Design have helped with digital fabrication advice and structural analysis of a small and potentially adaptable ‘garden office’. Tetra Shed is a free standing single-storey timber structure designed to create an architecturally striking and comfortable space that can be internally adapted to suit the unique requirements of every client whilst maintaining the same structure. Expected uses are as a home office, extended living space or commercial applications.
The structural frame builds upon the expertise Ramboll Computational Design have developed in the CNC fabrication and jointing of thin ply sections on the London Funnel and Trada Pavilion projects
In this unique project the client, digital film distributor Arts Alliance, wanted a lightweight, easily transportable venue to house its new performance of ID: Identity of the Soul on a worldwide tour. The brief required a structure that would meet the technical requirements for video projection and surround sound during live performances, as well as accommodating up to 3,500 people without impeding views of the stage. The structure had to be capable of being erected within two weeks and when demounted it had to fit inside a reasonable number of shipping containers for transportation across the world. It also had to be of the highest architectural quality.
Oslo-based practice, Various Architects proposed a dynamic oval form within an inflatable hexagonal PVC outer skin and drum-like fabric roof. Together with specialist contractor ESS, we developed a structural concept that has met the challenge.
After evaluating a number of different structural options an arrangement of radiating spokes, akin to the wheel of a bicycle, formed by tension cables running between inner and outer steel ring beams supported on steel lattice columns was chosen. The resulting structure is ultra-light, easily transportable and quick to assemble, whilst providing a large, clear space for the theatre area.
The exterior skin is self-supporting and consists of a web of inflatable fabric tubes coated in PVC, with translucent inflatable pillows as infill. To help generate the hexagonal pattern of the pneumatic skin, Generative Components software was used to parametrically control the size and scale of the hexagonal tessellations.
The Arts Alliance theatre is believed to be the largest mobile entertainment venue in the world measuring 90m by 40m on plan and in 2008 won the Spark Award.
Rambøll Computational Design (RCD) and artists Loop.ph have completed the design and erection of a 6m tall carbon fibre and perspex arch structure for Belvedere Vodka’s RED street party in New York, USA.
Taking over Manhattan’s Meatpacking district with a dramatic light show and music, the event was a one of a number of international celebrations in the run up to World AIDS Day on 1st December. World AIDS Day was first ever global health day, providing an opportunity to unite in the fight against HIV, show support for people living with it and commemorate those who have died from the disease.
Guests watched the area become illuminated in red against a backdrop of 20ft white neon trees to helpBelvedere Vodka and (RED)™ raise awareness of the campaign to eliminate the transmission of the HIV virus from mothers to their babies and achieve the first AIDS-free generation born by 2015.
The teams worked intensively for a month and collaborated on parametric 3d models in order to develop a form initially based on a flat pattern of 85 number, thin carbon fibre rods which was then warped and twisted to give the shape a natural stiffness. Perspex ribs linked the carbon rods together to ensure that the sculpture acts as coherent entity. The carbon fibre rods acted as natural conductors powering LED lights fixed in the corporate logo of Belvedere Vodka. Rambøll Computational Design provided structural engineering, 3d modelling, construction advice and practical assistance.
Just an hour before the production deadline, the Loop.ph and RCD teams finished assembling the structure and were able to pivot it into its final position. Shortly afterwards the New York public filled the square off Gansevoort and Hudson Street, milling around and under the arch, for a set by electro-funk DJs Chromeo to promote the cause.
Ramboll’s Trada Pavilion, a plywood structure inspired by the efficient curved forms of Frei Otto and Heinz Isler, was unveiled to the public for the first time this week at the Timber Expo 2012. The exhibition is the premier show in the UK for all those involved in the timber sector.
Trada commissioned Ramboll’s computational design team to design the timber pavilion, which was the focal point of the Timber Expo 2012 stand and one of the biggest draws at the exhibition. After this exhibition, the sculpture will showcased again on TRADA’s stand at the 2013 Ecobuild exhibition.
The team set themselves the challenge of creating a planar three-valent mesh approach for the double curved surface, rather than the conventional triangular mesh. A hexagonal mesh has the advantage of fewer connections and greater structural efficiency, but requires coding from scratch and a great deal of research. The final design utilizes techniques from the computer game industry coupled with engineering intuition.
Based on the team’s previous research into funicular form finding, the design uses weak springs to automatically generate a zero bending moment surface, enveloping a large trade stand and allowing the public to circulate underneath. It uses a mesh of thin plywood plates joined via simple expressed hinged pin connections. The structure was modelled with the extensive use of generative 3D systems with the output linked to a CNC router.
The KREOD (formerly known as Dpod) pavilion, located at the North Greenwich Olympic site, has now been completed – a significant event as it marks the culmination of a challenging design and fabrication process.
KREOD is a sustainable, portable, demountable and multi-functional indoor or outdoor exhibition space that will be installed in multiple locations within London. The project is led by Pavilion Architecture with its organic form inspired by nature, resembling a seed.
KREOD will sits on castors allowing the structure to be moved and rearranged into different forms and spaces to create a versatile event space with practical considerations for transportation, storage, disassembly and reassembly.
The structure, which has taken some time to come to fruition, is made up of three reciprocal timber gridshells that implement a number of geometrical optimisation and fabrication algorithms that have not been previously applied to a real structure. The form is a creative response to the need for a building that can be easily erected and subsequently demounted by hand, uses Kebony timber – a previously untried material – of a given size and limited thickness, and had to be delivered within a strict budget.
Using digital technology to its fullest, KREOD has been delivered in a collaborative manner with each member of the design team understanding the innovative work and challenges of the other contributors and designing accordingly.
KREOD will be launched and unveiled to the media today at its current site, adjacent to the North Greenwich Arena in East London, where it will remain for six weeks before being moved to its next site.
As part of the feasibility study into the most efficient structure for a dome over two hundred metres in diameter Ramboll Computational Design built upon and refined the techniques developed for the Tallinn Town Hall roof project. A double skin stick and node structure is automatically generated within the semi sphere volume first using the physical properties of a gas and then electrical repulsion to locate every node the same distance apart thus making every structural element the same length. This technique can be adapted to free form shapes and our software also allows for structural feedback and automatic reconfiguration to suit the stress distribution within the frame.
The design for the roof structure of the roof of a National museum in North Africa used our own software to automatically generate efficient funicular forms by dynamic relaxation. The components of the roof were thus uniformly tensioned, use a minimal amount of material and benefit from the visual harmony of repeatable section profiles throughout the space.
Our competition entry for the headquarters and research building of a large corporation in Finland exploited the ideas first postulated by Pier Luigi Nervi at the Gatti Wool factory in 1953. Lines of principle stress are joined to form ribs in the soffit of a reinforced concrete flat slab. The volume of concrete is reduced in comparison to a ‘conventional’ reinforced concrete slab, reducing emboddied carbon and enhancing the thermal mass characteristics. The exposed lines of structure are an expression of the reaction of the frame to external load. We have written our own software to model the stress vector field and resulting downstand ribs.
With Texere Studios, this was the first time we applied the research into digital urbanism and the science of emergent behaviour. taking the free roaming ponies in the new Forest as a inspiration for a traffic calming measure in a london site we helped with a design which created an inner city farm with sheep instead of horses.
Working with Foster + Partners we developed an in-house routine to automatically determine the optimum three dimensional roof form giving the right degree of internal solar shading in the new villa structures on the coastline of Montenegro.
The application automatically shapes the roofs of villas in relation to the solar shading needed. We were able to prove to Foster + partners the absolute minimum of roof overhang needed for this purpose.
A number of different parametric design tools were then used to set map the structure in an efficient manner on the doubly curved roof form such that the minimum amount of timber was used with the simplest orthogonal joints.
A least energy structure the form being determined by rcd’s own routines together with principle curvature mapping to form efficient framing
The timber members were set out in relation to the lines of principle curvature on the efficient surface. we developed the routines to do this and it enables a simple orthogonal structure to be set out on a complex surface.
Computational analysis of caternaries enhances 3D modelling capability
On a competition submission for Riga Airport, the RCD group used computerised analysis to model the undulating roof structure which was inspired by the catenary form. In the 19th century Gaudi defined the form of his iconic La Sagrada Família by making scale physical models using chains with hanging weights – catenaries.
In the case of the Riga Airport roof the form was found using the modern day computational technique of dynamic relaxation – a digital modelling tool ideal for analysing catenaries. The rationale behind Riga airport’s undulating roof surface was that it should dip where there are check-in desks and rise where natural light is needed to channel into the space below. At one end of the building the roof needed to drape down to the floor to create a sense of enclosure.
The initial geometry was created by the architect using some simple structural rules. Engineers then developed the geometry, maintaining the integrity of the shape but optimising the structural performance significantly using dynamic relaxation.
As a result the final design achieved the architects’ vision for an irregular curving roof while optimising the structure.
An algorithm inspired by electrical behaviour of sub-atomic particles rationalises a complex facade
Both archive and museum, the National Library will be a place for work and study, as well as education and tourism. A place for progress and a place for pleasure. As a national concentration of knowledge about the Kazakh culture and history, geography and demographics, government and presidency, the National Library will be a place for the people to learn about the president, as well as a forum for the president to meet with the people.
The initial scheme for the façade of the new Presential Library envisaged a triangulated diagrid of steel members set out in the form of a Möbius strip. If a ‘traditional’ rectilinear grid pattern were to be adopted for the setting out of the cladding panels then every panel and member length would be different making the façade package extremely expensive. The engineers’ challenge was to refine this complex and expansive steel façade structure to make it simpler and less costly to construct.
By applying an optimisation routine based on the theory of electrical repulsion engineers were able to refine the design so more panels were the same area and more supporting members were the same length.
The engineers created an algorithmic software script that ascribed to each nodal point in the facade a simulated electrical charge. Following the principle of electric repulsion, the nodes ‘repelled’ each other until they were evenly distributed, thus creating steel members of a standardised length.
A second algorithm was then used to push nodes towards areas of high stress, thus tuning the structure to the forces flowing within it, making it more structurally efficient.
Using digital intelligence to identify lines of principle stress in a structure.
For the competition-winning design of the new Greenland National Gallery the RCD group developed a reinforced concrete slab solution that looked original and striking while also being more energy efficient than a conventional reinforced concrete flat slab. The engineering design was based on extensive research into mapping stress flows through flat plate structures, using advanced digital tools. The concept uses new research into the actual stress flows through a flat plate structure and also revisits work from the early 1950’s by the great Pier Luigi Nervi.
Pier Luigi Nervi famously expressed the lines of principle stress in the reinforced concrete floor slabs of the Gatti Wool Factory. When he analysed the stress vector field, he used an intuitive approach based on trial and error.
The engineering team wrote a computer script to map stress flow pathways accurately and comprehensively. By mapping the principle stress vector field of a flat concrete plate with support locations based on the positions of columns in the building frame they were able to design a precisely calibrated slab, where slab thickness varies according to the structural requirement. When the stress flow paths are expressed in reinforced concrete they create elegant, curved, ribbed structures.
Computational analysis optimises uniquely curved form
D-Pod is a multi-use temporary grid shell structure. The architect’s original design (created using parametric software) posited each member as both curving and twisting. However, elements are often easier to fabricate if they are curved in one direction only. Connection detailing is also easier to standardise and therefore less costly if the curvature occurs only along one plane.
The engineering team created a digital tool to reveal the lines of principal curvature in real time to the designer. The architect was able to assess the curve network aesthetically before deciding on a final surface form.
Applying this curvature network constraint early made it easier to remove the twist effect and simplify connections once the design was finalised.
To make the shape of the grid shell more structurally efficient, the engineers morphed the underlying surface into a new position using a self-written script that integrated with the parametric software. Applying the principal curvature tool from the previous exercise to each new surface ensured the resulting structure was buildable.
The new town hall for Tallinn, the capital of Estonia, is a structure composed of 13 intersection boxes, the largest of which is a 60m tall tower comprising the main council
chamber and 37m high lightweight glazed façade. A deep roof structure incorporating a staircase to take visitors to a viewing arcHitect platform was required and as a result the
RCD team developed a tool for finding the most efficient way of fitting structure to the irregular volume of the roof void.
As well as providing support against wind and snow loading, the roof serves to prop the high side walls and huge glazed façade allowing lateral forces to be transferred to the stability core at the rear of the structure.
The tool that was developed used a routine that served to release a specified number of nodes into the volume. Each node is then given a simulated electrical charge so that they repel each other. When the nodes find an equilibrium position they are all an equal distance apart and members are drawn between adjacent points. As such a triangulated structure is derived where all members are of equal length. Engineering judgment was then used to refine the structure in areas of high or low structural density.
Algorithm mimics natural selection to evolve optimal structure.
The new town hall for Tallinn, the capital of Estonia, is a structure composed of 13 intersecting boxes, each of which cantilevers a considerable distance from inset columns at ground floor level. The side walls of each box are blank and therefore provided the opportunity to hide the arcHitect supporting cantilevering trussed frames.
The RCD group used the theory of genetic design to evolve and engineering solution that went beyond the traditional structural typology of a truss to deliver a more
The genetic algorithm was originally developed by John Holland in the 1960s and is a computer simulation of Darwinian evolution.
The engineers’ genetic algorithm solver initiated a population of possible truss arrangements which were assessed against a performance-related fitness criterion – in this case the deflection of the trussed frame. The resulting solution, which could not have been intuited using guesswork or traditional engineering assumptions, is the best optimised solution that effectively reduces deflection.