Structural optimization has become an important tool for structural designers, since it allows a better exploitation of material, thus decreasing structure self-weight and saving material costs. Moreover, it helps the designer to find innovative design solutions and structural forms that not only better exploit material but also give the structure higher aesthetic value from an architectural point of view. When applied to real scale structures like bridges, this approach leads to the definition of voids patterns delimiting regions where fluxes of force migrate from force application point to boundary regions and suggests innovative layouts without renouncing to formal and structural aspects. Nevertheless, the criticality of this powerful tool is related to the ease of defining entire families of possible candidate solutions, by modifying input volume reduction ratio to reduce structural weight as much as possible or defining several starting trial solutions based on the judgment of designer. In this case, structural optimization still leads to the best material distribution, but finding the best compromise between material saving and structural performance is a designer choice. To face this aspect, a global optimization index (GOI) has been defined and applied to the structural optimization of a steel-concrete arch bridge built is San Donà in the province of Venice, Italy. On the basis of this work, a generalized version of the optimization index is proposed and its analytical formulation is discussed in detail in this thesis. The application of proposed optimization index is extended from topology optimization to other optimization techniques. Moreover it allows not only to identify best candidate solution originated by a unique reference model, but even comparing structural performances between candidates solution derived by several starting trial solutions. Through structural optimization procedure performed on three different type bridges, namely footbridges supported by concrete shell, Calatrava Bridge (steel arch bridge) and two cable-stayed bridges, the effectiveness of proposed optimization index is validated. The results show that the proposed optimization index provides to the designer a mathematical procedure able to highlight the best choice among several candidate solutions obtained by the optimization procedure. With the proposed optimization index, a suitable score for each design solution of specific starting layout is assigned, therefore the best overall layout solution which is the best compromise between material saving and structural performance can be highlighted among single-family multi-solutions or multi-families or multi-solutions.

The main argument of the dissertation is structured around the relationship of innovation and modularity with a special focus on innovation openness. This research took a grasp in understanding the context, the classics, story of Italian design, and Made in Italy at the same time exploring design today: based on a field work in Milan, Lombardy. Case study method proved to be as most suitable for answering the explorative nature of this research. The approach was thus relying on secondary data, desk research and observation for understanding the context both from the angle of tradition and current discourse, as for reaching the next level: collecting cases worth to pursue. The cases presented were chosen to elucidate the targeted questions, and to open the path for further research. However, obstacles faced on the field narrowed the cases covered, and the breadth of the investigation of each case study. Limitations in data access did not allow going beyond the story, I had to rely on what was constructed by the company itself. Despite these obstacles the analysis benefited from the perspective of communication and branding: it made possible to investigate a complex innovation effort. This proved to be a valuable insight, since design-driven industries are driven by producing meanings, forming the discourse where communication plays a key role. This work explores what modularity means in production opening up the perspective toward the aesthetic and semantic realm of production of goods. Furthermore in search for the locus of innovation it examines the relationship of modularity, innovation and openness. By exploring architectural innovation [Henderson and Clark 1990] I found that core design concepts that define the direction of technological improvements enter the conceptual frame of innovation: • What was interpreted as ‘values’ by the company defining the design are proven to be core design concepts in the conceptual frame, as they define here a technological and conceptual [stylistic] frame. • Thus, architecture draws here a semantic and aesthetic frame of conveying meanings. [Not just merely defining the technological construction of the artifact described by the interaction of the elements]. • Procedural innovation [coined by me]: the effort that evolves around the main objective to most efficiently elaborate on the core design concepts in technological, and semantic realms. Further findings of the case studies suggest that open methodology of design and innovation is prone to come from third parties to established firms: • open design methodology as a communication strategy that contributes to innovation practices of the company, and not as a conscious strategy coming from the other way round. Here technological and communication tools are intertwined, as they are conveying meanings defined by the core design concepts • Firms in need for raising their capacities and reshaping organizational routines to innovate turn to third parties in the Knowledge-Intensive Business Services • elucidate hybrid forms of innovation Adding to theory The above-mentioned empirical findings were backed by a concise summary on: • open/ user/ collaborative innovation scholarship • links between modularity and innovation • and understanding the relationship of modular design in the history of design and architecture; also elaborating the: • Semantic frame of innovation: where the product is an architecture of meanings • Framework for understanding stylistic realm of conveying meanings and innovation • Linking modular design of products as a conceptual approach [aesthetics] and linking it to production from an evolutionary perspective Adding empirical insights to be considered for • Organizational theory: namely redefining the boundaries of the firm • Innovation openness: based on the locus of innovation • Modularity: apart from focusing on production, organization and that modular construction of goods has also a conceptual meaning (conceptually exploring the relationship of modular design and integrality with examples from architecture and classics of Italian design). Considering goods as an architecture of meanings and firms producing brands rather than goods, it draws on the implications of arrangement of production.