Pierluigi D'Acunto

Technische Universität München | TUM · TUM School of Engineering and Design - Professorship of Structural Design

Computational form-finding methods hold great potential concerning resource-efficient structural design. The Combinatorial Equilibrium Modeling (CEM), an equilibrium-based form-finding method based on graphic statics and graph theory, allows the design of cross-typological tension–compression structures starting from an input topology diagram in th...

This article presents a computational implementation for the Vector-based Graphic Statics (VGS) framework making it an effective CAD tool for the design of spatial structures in static equilibrium (VGS-tool). The paper introduces several key features that convert a purely theoretical graph and geometry based framework into a fully automated computa...

This paper presents a geometry-driven approach to form-finding with reused stock elements. Our proposed workflow uses a K-mean algorithm to cluster stock elements and incorporate their geometrical values early in the form-finding process. A feedback loop improves the reuse rate over multiple iterations, and a best-fit heuristic algorithm is used to...

The ability to work with both form and forces in the structural design process is crucial, particularly during the early design phase, as these are key parameters that impact the static behavior of a structure. Graphic statics offers a powerful geometric framework for the conceptual design of structures in static equilibrium, owing to the interdepe...

The research project presented here aims to develop a design-informed manufacturing process for complex concrete shell structures in additive manufacturing and thus overcome limitations of traditional construction methods such as formwork-and labor intensity. To achieve this, an effort was made to merge the two technologies of CNC knitted stay-in-p...

CantiBox is a robotically assembled pavilion composed of linear timber elements. The interweaving logic of the structure makes it possible to use exclusively interlocking timber-to-timber connections during the automatic assembly. The design of the connections is based on the static method of limit analysis, which allows adjusting the geometry of e...

This article presents a computational implementation for the Vector-based Graphic Statics (VGS) framework making it an effective CAD tool for the design of spatial structures in static equilibrium. Using synthetic-oriented and intuitive graphical methods, this framework can be used to design spatial structures in equilibrium as three-dimensional tr...

Key message Mechanical models of inosculations benefit from moderate geometric detail and characterisation of the structurally optimised area of interwoven tension-resistant fibres between the branches. Abstract Living architecture is formed by shaping and merging trees, often in combination with non-living technical elements. These structures oft...

The advancements in additive manufacturing (AM) technology have allowed for the production of geometrically complex parts with customizable designs. This versatility benefits large-scale space-frame structures, as the individual design of each structural node can be tailored to meet specific mechanical and other functional requirements. To this end...

This paper presents a novel construction system that integrates natural and artificial components through the case study of the Digital Bamboo. A reversible non-standard structure is made of unprocessed bamboo poles connected with 3D printed joints and covered by lightweight 3D-printed shading panels. The system combines multiple technologies to pr...

This paper proposes a computational approach to form-find pin-jointed bar structures subjected to combinations of tension and compression forces. The generated equilibrium states can meet additional structural and geometrical constraints via gradient-based optimization. We achieve this by extending the combinatorial equilibrium modeling (CEM) frame...

This paper presents a design strategy that aims to integrate structural and manufacturing considerations in the conceptual design of three-dimensional lattice structures for Injection 3D Concrete Printing (I3DCP). Early experiments with I3DCP showed that multiple structural and fabrication constraints need to be taken into consideration in terms of...

This paper introduces Text2Form3D, a machine-learning-based design framework to explore the embedded descriptive representation of structural forms. Text2Form3D relies on a deep neural network algorithm that joins word embeddings, a natural language processing (NLP) technique, with the Combinatorial Equilibrium Modeling (CEM), a form-finding method...

Graphic statics can be used as a design and analysis tool to develop discrete rigid-plastic stress fields and their underlying strut-and-tie models in reinforced concrete structures. This approach relies on the construction of reciprocal Airy Stress Functions (ASF) to generate form and force diagrams; these diagrams are subsequently combined into M...

Additive manufacturing allows using naturally grown structural elements in combination with 3D printed components, aiming to foster a more sustainable building culture. However, from a structural perspective, the combined use of natural and artificial materials introduces new uncertainties and challenges in relation to the design and analysis of th...

Research on mobile Augmented Reality (AR) technologies has proven many potentials and benefits for assisting craftspeople in various building applications within the AEC domain. However, little research has been done on the use of multi-user mobile AR systems coordinating several people at the same time. This paper examines the potentials of a coll...

Computational form-finding methods hold great potential for enabling resource-efficient structural design. In this context, the Combinatorial Equilibrium Modelling (CEM) allows the design of cross-typological tension-compression structures starting from an input topology diagram in the form of a graph. This paper presents an AI-assisted design work...

Building design is a complex, open-ended task that involves diverse disciplines and professionals. Architects and engineers are challenged with solving a variety of often-conflicting issues related to various aspects, such as space making, structural performance, energy consumption, and user comfort. Holistic design approaches allow for addressing...

Focusing on Frei Otto’s research on the use of physical models for conceptual structural design inspired by natural processes, this paper studies the implementation of the Vector-based Graphic Statics (VGS) tool for bio-inspired structural form finding. The VGS tool enables interactive generation and transformation of structures in static equilibri...

Reusing structural components has potential to reduce environmental impacts of building structures because it reduces new material use, energy consumption, and waste. When designing structures through reuse, available element characteristics become a design input. This paper presents a new computational workflow to design structures made of reused...

This paper proposes a computational approach to form-find pin-jointed, bar structures subjected to combinations of tension and compression forces. The generated equilibrium states can meet force and geometric constraints via gradient-based optimization. We achieve this by extending the Combinatorial Equilibrium Modeling (CEM) framework in three imp...

Structural engineers play an increasing role in ensuring the transition towards a more sustainable construction sector: a) they are responsible for the design of the most resource- and energy-intensive part of buildings and infrastructure, and b) they regularly interact with architects, contractors, and clients, and hence are full stakeholders in t...

Façade design is a multi-disciplinary process that involves qualitative and quantitative aspects belonging to diverse disciplines – such as architecture, structural design and building physics. Since decisions made in the early design stage generally have a strong influence on the design outcome, the need for a holistic design strategy is evident....

The paper presents a proposal for the structural preservation of the Basento Bridge in Potenza (1967-1975), designed by the engineer Sergio Musmeci (1926-1981) and regarded as one of the most relevant examples of 20 th century reinforced concrete infrastructures in Italy. The geometry of the Basento Bridge, which is the most characteristic feature...

Form finding is an effective approach for the conceptual design of structures. In the 1950s and 1960s, various form finding techniques flourished to create geometries that could not be realised with analytical models or graphical methods alone. The development of contemporary form finding owes much to the seminal work of a number of structural desi...

The design of building envelopes requires a negotiation between qualitative and quantitative aspects belonging to different disciplines, such as architecture, structural design, and building physics. In contrast to hierarchical linear approaches in which various design aspects are considered and conceived sequentially, holistic frameworks allow suc...

This article demonstrates the design potentials of a recently developed approach for generating smooth poly-hypar surfaces, freeform surfaces made of combinations of hyperbolic paraboloids (hypars). In a smooth poly-hypar surface, the double curvature of the individual hypar modules and the smooth connections between them ensure global bending-free...

The inherent interdisciplinarity in the design of building envelopes gives the opportunity to correlate different aspects within the boundaries of a single subsystem. In fact, designers have to account for parameters and criteria that belong to diverse fields – such as architecture, building physics, structural design and construction technology –...

This article introduces a novel equilibrium-based form-finding approach for air-supported structures that relies on vector-based 3D graphic statics and the Combinatorial Equilibrium Modelling (CEM). The proposed approach is particularly suitable for the conceptual phase of the design process, as it allows generating a wide range of design options o...

Although the analysis and design of structures in static equilibrium can be intuitively carried out using simple equilibrium-based methods such as graphic statics, the application of these methods to engineering problems that take into consideration specific material properties is generally limited. Within the domain of reinforced concrete, existin...

This article presents a computer-aided design framework for the generation of non-standard structural forms in static equilibrium that takes advantage of the interaction between human and machine intelligence. The design framework relies on the implementation of a series of operations (generation, clustering, evaluation, selection, and regeneration...

This article highlights the design potentials of a recently proposed form-driven approach for bending-active tensile structures, in which the geometry of the actively bent elements can be directly defined without the recourse to a form-finding procedure. The approach is applied to the design of a lightweight sun-shading system that can be used to p...

This article introduces a series of significant enhancements to the Combinatorial Equilibrium Modelling (CEM), a computer-aided form-finding approach to generate and control three-dimensional structures in static equilibrium based on topological considerations. In comparison to the initial formulation of the CEM, this article presents various proce...

Graphic statics are currently experiencing a renaissance for the analysis and design of structures in static equilibrium while also showing the potential of being applied to the solution of a wide range of problems in other fields of structural engineering. The constitutive objects of this geometrical methodology are the 'form' and 'force' diagrams...

Graphic statics can be effectively used for the analysis and design of structures in static equilibrium and for solving engineering problems related to specific materials, most notably, reinforced concrete. In this regard, methods for the construction of stress fields and yield lines, based on the theory of plasticity , are particularly valuable; h...

This article develops a vector-based 3D graphic statics framework that uses synthetic and intuitive graphical means for the analysis and design of spatial structures such as networks of bar elements in static equilibrium. It is intended to support the collaborative work of structural engineers and architects from the conceptual phase of the design...

From an architectural standpoint, folding as a design operation enables the creation of forms that can deal with different requirements in terms of both space and programme. Moreover, from an engineering perspective, folding is an effective strategy to generate efficient structures that withstand the applied loads through their form. Although these...

The Combinatorial Equilibrium Modelling (CEM) is a structural design framework based on graphic statics and graph theory [5] that allows to control directly the topology and the combinatorial state (distribution of the internal tension and compression forces) of a structure in equilibrium. The current development of the research extends the capabil...

The aim of this research is to introduce a novel structural design process that allows architects and engineers to extend their typical design space horizon and thereby promoting the idea of creativity in structural design. The theoretical base of this work builds on the combination of structural form-finding and state-of-the-art machine learning a...

This paper proposes a unified and entirely geometrical methodology for generating 2D and 3D force diagrams for given planar and spatial trusses in static equilibrium within the context of graphic statics. The trusses, regarded as form diagrams, are projections of higher dimensional simply-connected stress functions, can be either self—stressed or l...

In recent years, a renewed interest in structural matters and interdisciplinarity has risen, bringing forward challenges in professional and academic practices. The present work seeks to contribute to this discussion by unfolding a conscious proposition as implemented by the Chair of Structural Design at the Department of Architecture of ETH Zurich...

The reciprocity between form and force diagrams in 2D graphic statics makes it possible to manipulate the form diagram while directly evaluating the redistribution of the forces within the force diagram. Conversely, after modifying the force diagram, the consequent transformation of the form diagram can be assessed at once. In the case of vector-ba...

This paper presents an extension of the Combinatorial Equilibrium Modelling (CEM) design framework. CEM gives the possibility to generate and explore multiple spatial equilibrium solutions in the early conceptual design phase. In addition to the form and force diagrams of graphic statics, CEM introduces a topological diagram, which allows to adjust...

At the beginning of his career, the Italian engineer Sergio Musmeci (1926-1981) experimented widely with folded plate structures. Through the design of a series of reinforce concrete roofs, developed within a short time span (1954-1959), Musmeci exemplified his peculiar approach to structural folding by interpreting the principle of resistance thro...

Graphic statics provides an elegant and efficient method for equilibrium analysis of various types of structures. This is particularly the case for pin-jointed frameworks, for which the use of reciprocal form and force diagrams gives direct and simultaneous insights on the static behaviour of every structural member. On the other hand, plastic theo...

The evaluation of the equilibrium of a system of forces that fulfills specified boundary conditions is a core question of theory of structures. This paper reviews three methods, related to procedures introduced at the end of the 19 th century, to evaluate the global equilibrium in three dimensions using graphic statics. The paper is specifically fo...

Thanks to the experimental nature of his work, Sergio Musmeci (1926-1981) holds an exceptional position within the Italian School of Engineering of the postwar period. Musmeci's peculiar view on structural design is supported by the search for novel structural forms, which is initiated by his exploration on structural folding. In particular, during...

This paper presents an extension of the graphic-statics-based framework called Combinatorial Equilibrium Modelling (CEM). CEM allows for the generation of topologically and combinatorially different spatial equilibrium solutions in the early explorative design phase. In addition to the form and the force diagrams, CEM introduces a topological diagr...

This paper presents an approach to the extension of graphic statics force diagrams to the third dimension. The main focus is to build 3D force diagrams out of vectors, so that each edge in the form diagram corresponds to two parallel vectors in the force diagram; this pair of vectors can generally be overlapped to form one single edge. The issue of...

This paper introduces a generative design method for architecture grounded on the stereotomic approach. The method is based on the application of the Boolean subtraction operation to integrate spatial and structural parameters in the conceptual phase of the design process. Working on a three‐dimensional form, which is displayed and studied as a sol...

This paper presents an extension of the graphic-statics-based framework called Combinatorial Equilibrium Modelling (CEM). CEM allows for the generation of topologically and combinatorially different spatial equilibrium solutions in the early explorative design phase. In addition to the form and the force diagrams, CEM introduces a topological diagr...

The evaluation of the equilibrium of a system of forces that fulfils specified boundary conditions is a core question of theory of structures. This paper reviews three methods, related to procedures introduced at the end of the 19th century, to evaluate the global equilibrium in three dimensions using graphic statics. The paper is specifically focu...

The use of folding in design allows for the production of efficient structures capable to resist the external applied loads by form; additionally, folding is an effective way to generate forms that can address diverse spatial necessities. Developed as an entry to the IASS Expo 2015 out of a collaboration between the Chair of Structural Design at ET...

The present research is primarily focused on the investigation of architectural folding in the form of folded-plate structures. The goal of the research is to introduce a novel design method to consistently integrate structural folding in architecture. The proposed method is aimed at supporting the design process starting from the early conceptual...

Lightweight structures are conventionally associated to membrane and pneumatic constructions. Aiming at rethinking this paradigm, a research collaboration between the EmTech Programme (AA School, London) and the DARCH Chair of Structural Design (ETH Zurich) has been recently activated to explore the potentials of the use of plywood in lightweight s...

The project BRIDGE+ exemplifies how digital computational tools can be actively used for the design of a system of inhabitable footbridges in the Norwegian cities of Skien and Porsgrunn. Thanks to its flexibility, evolutionary computation has been chosen as the main tool for the design process. Indeed, the use of evolutionary computation allowed fo...

In this paper the energy performance of a residential building in Paris, designed within the International Architectural Competition HABITER PARIS (as concerns the suburban quarter of Porte des Lilas) are analyzed. According to EN 12831 and EN 832 the building winter energy demand has been evaluated to prove the low-energy-consumption behaviour of...