This research explores the use of natural stones as a sustainable construction material, leveraging their low embodied energy and local availability. However, traditional stone masonry relies on skilled craftsmanship, which is increasingly scarce. To address this challenge, we develop a robotic planning system for autonomous stone layout, focusing on geometric optimization and structural performance. Our method translates traditional masonry principles-such as dense packing, joint interlocking, and course horizontality-into a multiobjective optimization framework for stone selection and placement. The algorithm minimizes gaps, maximizes stability, and ensures feasible configurations through discrete convolution techniques. Additionally, we employ a microscale rigid block modeling approach to assess structural behavior, simulating wall behaviors under shear-compression loading. In a case study, we virtually construct two 0.7 m × 0.7 m × 0.4 m walls using digitized stones, comparing layouts generated with full and partial optimization. Results show that walls built with the complete algorithm exhibit comparable force capacity and stiffness to mason-built walls, while partially optimized walls demonstrate reduced performance. This work advances robotic stone construction by enabling high-fidelity microstructure generation and load-bearing assessment, promoting sustainable building practices through automation.

The database of tests conducted in masonry walls shows that shearcompression tests are performed using a wide range of wall heights from under 1.0 m to 3.0 m. The results of these tests indicate that shorter walls tend to reach larger drift capacities; however, there is no systematic study investigating size effects within a single experimental campaign. Moreover, most walls tested on a reduced scale tend to only decrease the overall size of the wall but keep the size of the brick due to the difficulty of manufacturing scaled bricks. This document presents an experimental study of the size effect on the drift capacity of unreinforced masonry walls built with hollow clay bricks and standard cement mortar. A total number of six quasi-static cyclic tests have been conducted for three different wall sizes (heights of 2.8 m, 2.0 m and 1.4 m) and two different levels of compression load (axial load ratios of 0.10 and 0.20). All the walls had the same aspect ratio (L/H) of 0.75 and were tested under double bending boundary conditions to observe a shear-controlled behaviour. This work analyses the mechanical phenomena on the different wall sizes and the consequences observed in the seismic behaviour. Particularly, this study focuses on the influence of the wall size on the drift capacity and how the crack pattern and crack opening play a role in this behaviour. Furthermore, this research also provides a reference for how small test specimens can be for obtaining drift capacity values in storey-high walls.

Stone masonry buildings are vulnerable to a wide range of loadings, such as differential settlements and earthquakes. Damage to these buildings manifests itself mainly through cracks in the masonry walls, which often propagate along the interface between mortar and stone. In this study we investigate the role of the stone surface roughness on the interface shear strength, which is described through the Mohr-Coulomb failure criterion. To do so, we subject samples consisting of two units and one mortar joint to direct shear loading and a constant normal load. For the stone unit we used as proxy high-strength concrete that was cast against 3D printed surfaces with artificial surface roughness based on sinusoidal waves and vary the wavelength and the amplitude of these waves. We conducted 85 tests and analysed the influence of the wavelengths and amplitudes that characterise the surface roughness on the shear behaviour. We propose simple Mohr-Coulomb-based equations incorporating additional surface parameters. Based on which we can confirm that see that increasing surface roughness enhances peak, residual friction coefficients and cohesion.

We developed a series of open databases regarding the mechanical characterization of rammed earth across scales-from material tests on small-scale specimens to shear-compression tests on large-scale walls. The databases provide information related with manufacturing, material and mechanical properties. Here we present an overview of the databases along the main challenges related with their development and analysis. Challenges regarding data collection concern mainly the lack of a systematic reporting of material properties, manufacturing details, testing procedures and experimental results. Challenges during data processing include lack of standardised test procedures, the large variability of soil composition, and the comparison of data coming from different sources. Despite these challenges, the developed databases provide a valuable resource of experimental data on rammed earth, give insights over research gaps and promote an understanding of rammed earth construction, facilitating its broader use for sustainable construction. We believe that continued efforts to establish standard testing and data sharing procedures are essential, as they can significantly contribute to the further enrichment of these databases. The database is provided as open access and it will be continuously updated with new available experimental data.

Northern Pakistan's mountainous regions, including Khyber Pakhtunkhwa and Azad Jammu Kashmir, are among the most seismically active in South Asia. Traditional rural housing in these areas-often built with dry stone masonry and mud mortar-reflects generations of vernacular knowledge but lacks seismic resilience. Modern construction methods are rarely adopted due to cost, inaccessibility, and lack of construction skills. This project explores a hybrid, locally adapted retrofitting strategy that builds on traditional techniques, integrating them with modern tools and analyses. We aim to combine: (1) optimized stone placement; (2) optimized timber reinforcement; and (3) digital twinning. The ongoing exploration phase of Tech4Dev programme (May-August 2025) focuses on community co-design. Activities include stakeholder workshops, field surveys, and collaborative workshops in partnership with UET Peshawar and Sarhad Rural Support Programme. Our aim is to develop retrofit solutions that are not only technically sound, but also economically viable, environmentally lowimpact, and culturally accepted. By aligning innovation with tradition, this project seeks to create a replicable model for seismic risk reduction in rural mountainous areas.

In response to current climate considerations, the geotechnical sector is increasingly exploring multiphysical approaches to develop sustainable engineering projects. This thesis focuses on two promising applications that combine the sector's decarbonisation objectives with geomechanical functionality: energy geostructures and biocementation. Multiphysical modelling has played a key role in their development and remains an essential tool to advance innovation adoption.

For energy geostructures, modelling and design frameworks are well established. The remaining challenge is to extend the domain of application beyond its well-known uses, primarily energy pile foundations in balanced climates, and demonstrate their effectiveness in alternative scenarios. In contrast, modelling frameworks for biocementation are often not validated at the large scale. Upscaling also continues to pose challenges, and recommendations for overcoming these are not readily available. These problems obstruct the step towards design principles.

In this setting, the thesis has a twofold objective: (i) to extend the range of applications for energy geostructures by moving beyond conventional considerations and (ii) to move towards developing design approaches for biocementation treatment. By building on existing knowledge and using multiphysical modelling as a central tool, the research offers new insights into the design, optimisation, and application of these technologies and aims to support future sustainable geotechnics.

Numerical analyses are used to look at three different settings for the application of energy geostructures. The potential of energy piles to provide cooling energy in hot-dominated climates is demonstrated through simulations, which show that, despite unbalanced thermal demands, temperatures stabilise over time and respect heat pump limitations. Simulations reveal that geothermal activation of an underground data centre can reduce internal air temperatures, and this effect can be used to optimise ventilation system performance but requires a case-by-case evaluation. Finally, models are used to understand the internal air dynamics of an energy metro station, and recommendations are provided for how such factors can be accounted for in its design. These works demonstrate that through modelling, the technology can be optimised to maximise its impact in providing renewable thermal energy.

The work then demonstrates how multiphysical modelling can aid in achieving standardisation of biocementation. A modelling framework is benchmarked against upscaling experiments to assess its performance. Recommendations for achieving homogeneity in biocementation soil improvement are provided, highlighting the benefits of using high, consistent injection rates and demonstrating the effect of using novel injection geometries. The framework is then adapted to simulate treatments using an ex situ hydrolysis method, revealing a shift in the governing precipitation mechanism from urea hydrolysis to calcium carbonate precipitation kinetics in relation to mixing patterns. Last, the effects of different treatment configurations for slope stabilisation via biocementation are analysed using both limit equilibrium and finite element methods. While biocementation can improve slope stability, its success largely depends on the manner of application. These findings highlight the contribution of modelling in developing effective approaches for biocementation treatment.

The electrochemical reduction of CO2 for producing carbon-neutral fuels and chemicals is a pivotal technology for the future decarbonization of the chemical and energy sectors. Among the various electrolyzer architectures, forward bias bipolar membrane (BPM) systems have emerged as a promising solution, combining high selectivity and CO2 utilization with a pure-water feed, salt-free design. However, performance limitations arising from water transport imbalance, membrane degradation, and kinetics overpotentials at the membrane interface hinder their industrial deployment.

This thesis addresses these challenges through systematic investigations across four key axes. The first part focuses on water transport, using synchrotron-based, operando X-ray tomography and diffusion measurements to analyze water management and hydration dynamics in a commercial BPM-based cell. It reveals that cathode flooding is not a limiting factor at the investigated current densities (up to about 200 mA cmâ 2), as the GDL saturation stays below 10%. Instead, insufficient water supply to the cathode and membrane over-swelling are identified as the dominant challenges for high current density operation.

The second part focuses on degradation mechanisms within the membrane-electrode assembly. Pre- and post-mortem analysis, again by X-ray tomography, reveals the evolution of structural damage. We show that membrane delamination occurs at current densities above 100 mA cmâ 2. To resolve this, a series of semi-porous BPMs with engineered gas-permeable anion exchange layers is designed and investigated. These structures enable enhanced back-transport of recombined CO2 toward the cathode, thereby relieving interfacial pressure buildup at the membrane junction. Among the tested designs, a microporous ionomer-nanoparticle composite layer proves particularly effective in suppressing membrane delamination under up to 200 mA cmâ 2 and reducing anode catalyst layer damage area by up to 90% compared to commercial BPMs.

The third part addresses the kinetic limitations at the BPM junction by integrating metal-oxide catalyst layers (e.g., TiO2, SiO2, IrO2) directly at the membrane interface. Complete catalyst coverage at 20â 30 ÎŒg/cm2 enables up to 100% higher current density at similar iR-corrected voltages, providing a scalable strategy to overcome interfacial limitations.

Finally, the fourth part investigates the role of the catalyst-layer microenvironment and its influence on reaction kinetics in cation-free systems. By designing a fully gas-fed setup with pretreated membranes, the study isolates and evaluates the impact of trace alkali cations migrating across the membrane. Furthermore, the use of anion exchange ionomers with high ion-exchange capacity (IEC) is found to promote beneficial double-layer capacitance and stabilize the catalytic interface over multi-hour operation. The results support a mechanism where both mobile and fixed cations shape the local environment on the silver catalyst surface, thereby enabling stable CO production under pure-water-fed, salt-free conditions.

Altogether, this work presents a comprehensive framework for enhancing the performance of a pure-water fed CO2 electrolyzer with a BPM in forward bias. By coupling advanced diagnostics with targeted material strategies, the thesis contributes to both fundamental understanding and practical design principles to guide the next generation of scalable and durable CO2 electrolysis systems.

The development of soft electronic and optoelectronic systems is essential for the growth and industrial deployment of research fields such as smart textiles and wearables. However, it remains challenging to identify materials that reconcile the required mechanical attributes (e.g. softness and stretchability) with functional metrics essential to develop high-performance devices (e.g. electrical conductivity or photoconductivity). Moreover, it is equally important to find processing routes that can produce such devices at large scale and low-cost while ensuring an accurate arrangement of materials with disparate electronic properties into complex architectures with small feature sizes.

In this thesis, we investigate the thermal drawing technique as a strategy to produce soft, multifunctional electronic and optoelectronic fibers. Originally developed for optical fibers, this process leverages the viscous flow of materials to transform macroscopic assemblies into long fibers while preserving the initial cross-sectional architecture. In particular, this work focuses on implementing the three fundamental pillars of soft optoelectronic devices within thermally drawn fibers: (i) Stretchable and electrically conductive materials serving as electrodes for charge collection and transport: Two composite systems relying on rigid and liquid fillers dispersed in a soft matrix are proposed, and their performance is demonstrated through various types of mechanical sensors. In particular, highly stretchable and conductance-stable electrodes are established in thermally drawn fibers by relying on liquid metal embedded elastomers. (ii) Transparent conductors that simultaneously enable light transmission and charge transport: The introduction of ionogels as a novel materials system in thermally drawn fibers is demonstrated. The versatility of this material enables a fine tuning of its mechanical, electrical and thermal properties to match the targeted attributes for specific applications. In particular, meters-long stretchable fibers encompassing a transparent and conductive core are produced, marking the first implementation of a transparent electrode in thermally drawn fibers. (iii) Stretchable semiconductors functioning as active layers with light-responsive properties: Blends of organic semiconductors with thermoplastic elastomers are envisioned as a facile route to produce soft semiconductors with low processing temperature that can be easily introduced into thermally drawn fibers. Each material system is first studied individually, then integrated into a single soft fiber demonstrating optoelectronic properties. This work paves the way towards the development of complex multi-functional soft fibers to fabricate smart textiles and wearables with advanced electronic and optoelectronic properties.

This thesis presents a comprehensive study on the application of composite magnets in two industrial scenarios: the development of a linear actuator and the enhancement of ski equipment with magnetic attachment systems. In both cases, non-uniform magnetization is employed, specifically in the form of a continuous adaptation of the Halbach array.

In the first application, the thesis explores the replacement of sintered magnets, typically used in permanent magnet motors, with composite magnets to reduce production costs while maintaining performance. The final prototype is functional but delivers a force reduced by 30% compared to the original. The thesis also presents an optimization of the stator's ferrous body, allowing for in-situ winding and further reducing manufacturing costs.

The second application aims to replace the traditional glue used with climbing skins with a flexible composite magnetic strip to enhance user experience. This technology is applied to two cases: cross-country skiing and mountaineering. For the latter, the results are promising but require further development, particularly in achieving sufficient magnetic force. In contrast, the cross-country skiing case result in a working product and to the development of a production line ready to supply the first batch of magnetic skins.

The thesis covers the design and optimization of magnetic patterns, as well as the development of a magnetizer tailored to this application, using finite element analysis and prototyping. For the cross-country case, a cooling system is developed to achieve a production rate that aligns with industrial needs.

The results of the thesis demonstrate the potential of composite magnets and the possibilities offered by unconventional magnetic patterns, paving the way for future advancements in magnetic material technology.

The Marshall Plan was the cornerstone of U.S. Cold War economic and foreign policy. It was a program of technical assistance to set up free trade through European integration, of mutual security to prevent the spread of communism through the Atlantic Alliance, and of information, education, and cultural exchange to promote the American Way of Life. Devoting specific attention to labor affairs to prevent strikes and communist tendencies among workers, Labor Division of the Marshall Plan advocated a transnational workers' housing program, notably in France, Greece, Italy, and Turkey as well as the Allied-controlled Austria and Allied-occupied Germany, for union-sponsored housebuilding and homeownership.

The program was framed around the discourse of non-communism, free labor, and the free world, disseminated jointly with the International Confederation of Free Trade Unions (ICFTU). Providing financial and technical assistance to trade unions for establishing and managing housing cooperatives, training construction labor in housing development and design, and industrializing building trades were key elements of this program, jointly organized with the ICFTU's European Regional Organisation, trade union federations and governments.

Union-sponsored cooperative housing was promoted for industrial workers as a means to assert authority and autonomy in housing provision, to build a home of one's own and a house with a garden, symbolizing upward mobility. This vision promised labor stability through union affiliation and mortgage loans, while advertising domestic ideals of a preindustrial way of life. Built on U.S. New Deal and wartime legacies on union-sponsored housing and advanced by Scandinavian models of non-profit housing associations, the program functioned as a multilateral U.S. Cold War Project, and grafted real-estate dynamics onto public housing, regardless of local policies and housebuilding traditions of the participating countries.

This thesis offers methodological insights to architectural history and theory. First, I survey non-architectural archives of governmental and multilateral organizations and develop my arguments using correspondence, memoranda, reports and "picture files" as well as photographs, press clippings, and a film script, rather than architectural archives and drawings. Second, I explore trade unions as authors of housing development, design and construction, and integrate social history into architectural historiography for a wider understanding of built environment production and its non-architect agents. The thesis also offers new historical findings and theoretical perspectives. First, I introduce the Marshall Plan's workers' housing program, overlooked except some country-specific studies on its involvement in housing and domesticity. Second, I present the U.S. architect-planner Donald Monson and U.S. labor advisors as key actors, along with previously unexamined U.S. housing consultants. Third, I discuss self-help housing as a tool of postwar imperialism in Western Europe, beyond postcolonial frameworks dividing the "global west/north" from the "global east/south," and I propose multilateral imperialism as an alternative to scholarship that interprets cross-cultural exchange through the lens of global governance. Finally, I demonstrate the agency of union-sponsored cooperatives in shifting workers' housing toward a real-estate market through self-acquisition of land and tenant-ownership model.