Musée des Civilisations de l’Europe et de la Méditerranée: A Sustainable Fusion of Heritage and Innovation Through Ultra-High-Performance Concrete

Abstract

The Musée des Civilisations de l’Europe et de la Méditerranée (MuCEM) in Marseille represents a paradigm shift in sustainable architecture, integrating heritage conservation with cutting-edge material technology. Designed by Rudy Ricciotti, the museum utilizes Ultra-High-Performance Concrete (UHPC) to optimize structural efficiency, environmental resilience, and architectural aesthetics. This study highlights how UHPC contributes to reducing resource consumption and enhancing durability, in line with global sustainability goals. MuCEM’s lattice facade, modular supports, and pedestrian bridge showcase innovative engineering solutions that extend the building’s lifespan while ensuring seismic resilience and energy efficiency. Furthermore, UHPC’s longevity reduces maintenance requirements, contributing to lower life cycle costs and carbon footprint. The findings underscore how advanced materials and sustainable design principles can redefine the role of cultural landmarks in the built environment.

1. Introduction

Sustainable architecture seeks to balance cultural heritage preservation, environmental responsibility, and material efficiency to create resilient and enduring structures [1,2,3]. The Musée des Civilisations de l’Europe et de la Méditerranée (MuCEM) in Marseille exemplifies this approach by integrating Ultra-High-Performance Concrete (UHPC) with historical continuity and cutting-edge technology [4,5,6]. Designed by Rudy Ricciotti, MuCEM is a cultural and architectural landmark that demonstrates the potential of advanced concrete materials to enhance structural longevity, resource efficiency, and environmental resilience [7].

The primary objective of the MuCEM project was to create a structure that embodies a synthesis of heritage and innovation—respecting the historic and cultural identity of Marseille while pioneering new possibilities in architectural design and material application. The use of UHPC was central to this vision. It was selected not only for its superior mechanical and durability properties but also for its capacity to enable novel architectural forms, reduce material usage, and ensure long-term environmental resilience. From the intricate lattice facade to the slender pedestrian bridge and modular structural supports, UHPC allowed for the realization of lightweight, complex geometries that would have been unfeasible with conventional concrete. These choices reflect a deliberate strategy to minimize the environmental footprint, maximize structural performance, and create a cultural landmark that exemplifies sustainable construction and forward-thinking design.

The MuCEM is a significant architectural highlight in Marseille, the 2013 European Capital of Culture, and is notably the first large-scale building to extensively utilize UHPC [8]. Several innovative applications of UHPC contribute to the museum’s distinctive appearance, including a 115mlong walkway that spans 76 m freely with a height of only 1.80 m, and 308 organically shaped tree columns employing the post-tensioning of vertical fiber concrete elements for the first time. Additionally, the building features a 20 mm thin running surface on the 820mlong suspended ramp that encircles the structure between the shell and the core.

The UHPC lattice panels that envelope MuCEM’s façade and rooftop are inspired by traditional Mediterranean Mashrabiya screens, yet they are reimagined through advanced material technology. Each panel measures approximately 3000 mm × 5800 mm and is just 80 mm × 70 mm in cross-section—remarkably slender for a structural element of this size. Despite their perforated appearance, these panels are partially load-bearing, designed to resist lateral wind pressures and self-weight while preserving transparency and light modulation. The unique strength–weight ratio of UHPC, coupled with its low porosity and high tensile strength, allows for the retention of structural integrity even with significant void percentages.

Ultra-High-Performance Concrete (UHPC) used in MuCEM exhibits compressive strengths ranging from 150 to 200 MPa, which is approximately three to four times higher than conventional high-performance concrete (HPC), typically rated at 50–90 MPa. In addition, UHPC demonstrates a tensile strength of 7–10 MPa and a flexural strength exceeding 40 MPa when reinforced with steel or synthetic fibers. This enables the casting of ultra-thin structural sections that still meet demanding load-bearing requirements. UHPC’s dense microstructure also results in extremely low water absorption (<0.2%) and chloride ion permeability, making it ideal for marine environments where corrosion and saltwater degradation pose significant risks. These characteristics collectively offer superior performance, durability, and formability, which were essential for achieving the MuCEM’s complex geometry, long-span bridge, and maintenance-free structural façade [9,10].

While a full MuCEM-specific life cycle assessment (LCA) was not performed, comparative data from peer-reviewed sources present strong evidence of the environmental benefit of UHPC compared with common concrete in equal structural use [11]. Its improved mechanical properties and dense matrix enable decreased section thickness to be employed, conserving 25–40% of raw material [9]. Its very high durability—typically greater than 100 years with minimal upkeep—corresponds to significantly reduced lifecycle greenhouse gas emissions and resource use [12,13]. Studies show that UHPC structures can realize 30–50% of total embodied CO₂; reductions throughout their lifetimes, particularly when utilized in members such as long-span bridges, slender facades, or seismic-resisting columns [14]. In the MuCEM case, where the lattice structure of the UHPC, bridge, and modular supports replaced heavier reinforced concrete elements, the use of the material provides a substantial reduction in the initialand periodic environmental loads and brings the project in line with sustainable long-term objectives [15].

UHPC is emerging as a superior alternative to traditional construction materials due to its outstanding physical and chemical properties [16]. With a projected lifespan of 100 years, UHPC is significantly more durable than conventional concrete, boasting compressive strength six to eight times higher and nearing that of steel. Its fine metal and synthetic fibers impart excellent tensile strength. The closed-cell structure of UHPC makes it airtight, waterproof, and resistant to aggressive chemicals and saltwater. Fiber concrete has been utilized for 20 years in applications such as chemical tanks, sculptures, steps, and facade elements. Since 2002, pilot projects have employed UHPC mainly in pedestrian bridges. However, UHPC also offers new design possibilities; it can be compacted to create sharp edges and thin profiles unusual for concrete, allowing for the casting of delicate, freelyformed geometries suitable for sunshades and other applications [9,10].

The MuCEM is particularly notable for its extensive application of UHPC, a material characterized by its exceptional strength, durability, and versatility. UHPC’s incorporation into both structural and aesthetic elements of the building allows for unprecedented design freedom and structural efficiency. From the intricate latticework of the facade to the innovative modular tree columns, UHPC plays a crucial role in defining the museum’s architectural identity.

This study offers an in-depth study of the Musée des Civilisations de l’Europe et de la Méditerranée (MuCEM) with the overarching theme of UHPC’s integration into the design and construction of the building. Emphasizing sustainable development and structural innovation, the article discusses how UHPC enabled the creation of complex architectural elements—such as the pedestrian bridge, modular supports, and perforated façade panels—while meeting the demands of durability, seismic resistance, and sea exposure. MuCEM is thereby presented not simply as a cultural icon but as a paradigm of high-tech material application in contemporary architecture. The analysis is structured around the following research questions: (1) In what ways does UHPC make possible structural and aesthetic forms unachievable with ordinary concrete? (2) How does MuCEM’s use of UHPC resolve concerns over seismic performance, environmental sustainability, and accuracy of fabrication?

Together, these questions frame MuCEM as an exemplary case study in the architectural potential of high-performance concrete and the catalyst for sustainable, context-sensitive design.

2. Historic and Contemporary Architectural Design

Situated on a headland at the entrance to the Vieux Port, the Musée des Civilisations de l’Europe et de la Méditerranée (MuCEM) stands as a testament to innovative architectural design, merging historical references with contemporary material applications [17]. The building’s façade, which appears monolithic and homogeneous from the outside, intentionally evokes the ancient, solid walls of the nearby Fort Saint-Jean. This connection is further emphasized by a bold pedestrian bridge linking the museum to the fortress, reinforcing the thematic continuity between historical and modern elements (Figure 1).

The architectRudy Ricciotti designed this contrast between the building’s seemingly solid exterior and the intricate, lace-like façade in response to both historical context and climatic demands. The organic grid pattern on the building’s surfaces creates dynamic plays of light and shadow, reminiscent of sunlight reflecting off water, thus establishing a visual link with the Mediterranean horizon and North Africa (Figure 2). This design also draws parallels to Mashrabiya screens, traditionally ornately carved wooden or stone lattices in Arab architecture, aligning with the museum’s thematic focus on the cultural and historical diversity of the Mediterranean region [18].

The building’s shell functions as an external sunshade, strategically positioned where solar exposure is most intense: on the south and west façades, and above the roof area. The main entrance is located on the north side at ground level, marking the beginning of the “architectural promenade”. This series of ramps encircling the building, reminiscent of ancient Mesopotamian ziggurats, guides visitors upward through the exhibition spaces while interacting with the delicate grid of the façade. This spatial experience, enhanced by the tree-like UHPC supports that overlay the orthogonal grid of the glass façades (Figure 3 and Figure 4), amplifies the sensory transition between different realms [15].

The MuCEM is not only a technical feat but also a cultural gesture. The use of UHPC plays a vital role in translating regional identity into contemporary form. The lattice shell, inspired by traditional Mashrabiya patterns found across Mediterranean architecture, reinterprets this heritage through a modern material language—one capable of achieving fine, porous textures that modulate light and air. The pedestrian bridge, linking the museum with the historic Fort Saint-Jean, is more than a connector; it embodies the architectural dialog between the past and present. UHPC’s versatility makes this dialog possible, enabling the building to visually and structurally integrate the weight of history with the openness of modern design. In doing so, the MuCEM asserts itself as a vessel of memory and innovation—where cultural continuity is preserved not by imitation, but by thoughtful reinterpretation through material and form.

The design of MuCEM is deeply rooted in its Mediterranean context—not only in symbolic and cultural terms but also in its response to the region’s climate. The UHPC lattice shell of the building acts as a passive solar screen, shutting out intense southern and western sunlight while admitting airflow and dynamic daylighting. This significantly reduces thermal gains and enhances interior comfort without resorting to mechanical means. Furthermore, the ventilated facade space betweenthecore glass cube and facade serves as a thermal buffer, reducing cooling loads during summer and heat loss during winter. Material selection also considered the sea environment: high resistance of UHPC to salt spray, UV radiation, and humidity ensures long-term operation and minimizes degradation. Together, these strategies exhibit a very sophisticated understanding of bioclimatic design, thoughtfully modified to the hot, salty, and capricious Mediterranean climate.

3. Structural and Aesthetic Innovations in MuCEM

3.1. Pedestrian Bridge: Monolithic Aesthetics

The MuCEM features a striking pedestrian bridge that extends 115 m from the museum’s roof terrace to the Saint-Jean Fortress, which houses additional parts of the museum’s collection. This slender, high-performance concrete structure exemplifies modern engineering and design, creating a seamless visual connection between the museum and the historical fortress [19].

The bridge’s dramatic design is accentuated by its descent from the fortress’s historic stone materiality to the sleek, contemporary form of the high-performance concrete footbridge [20]. The journey begins with a descent from the traditional stonework of the fortress, leading onto the gently inclined bridge, which represents a transition into the world of advanced material technology (Figure 5).

Structurally, the bridge presents an illusion of monolithic continuity, achieved through the use of two integral beams that also function as railings. These beams are crucial in maintaining the bridge’s static requirements, with a height of 1.80 m and a clear span of 76 m. The bridge is constructed from 25 prefabricated segments, each 4.5 m long, which are connected through post-tensioning to form a cohesive supporting structure, akin to a string of pearls.

The bridge’s imposing presence and its combination of straight lines and sinuous curves seamlessly connect the two buildings—one historic and one modern—while remaining contextually appropriate and harmonious with the MuCEM [21]. The surface of the bridge features visible holes, which mark the assembly points of the prefabricated components (Figure 6). These marks have been deliberately left exposed by the architect to both showcase the bridge’s construction process and facilitate future maintenance.

The precision of the joint interfaces between the bridge segments is critical, with an allowable tolerance of only 0.1 mm. This exacting standard exemplifies the high level of precision demanded by contemporary engineering (Figure 6).

MuCEM’s pedestrian bridge required extraordinary geometric precision, with tolerances of only 0.1 mm for fitting segments. To this end, production started with numerically controlled steel formwork to deliver repeatable precision on several segments. Digital scanning and 3D checking of the formwork prior to casting ensured meeting design requirements within sub-millimeter tolerance [19].

At onsite installation, total stations employing laser guidance positioned each prefabricated unit of UHPC. The bridging structure with modular construction involved steel sleeves internally and alignment keys allowing for the fitting together of the segments with only minimal manual realignment. Positioning in its final form utilized hydraulic jacks and post-tensioning tension checks and introduced micro-adjustments in real time during construction. Offsite dry-run full-scale installations at-site were carried out to meet dimension compliance before placement in final form. These steps individually allowed the bridge project team to satisfy the unusual tolerance requirement for the bridge by ensuring aesthetic integrity and long-term durability [15].

3.2. Geometry of the Modular Supports

The MuCEM incorporates a sophisticated system of 308 prefabricated modular supports that encircle its three exhibition levels (Figure 7). These supports exhibit a diverse range of geometries, categorized into three primary groups:

Straight Supports: These come in two forms—those with a constant cross-section and those with a tapered cross-section.

Y-Shaped Supports: Available in nine distinct variants, these supports introduce an array of structural and aesthetic options.

N-Shaped Supports: Featuring two variations, these supports provide additional structural versatility.

Each type of support can be installed in mirrored configurations, effectively doubling the number of unique variations possible. The supports vary in diameter from 0.25 m to 0.40 m, and their heights are tailored to different floor levels: 2.79 m, 5.51 m, 6.12 m, and 8.79 m, respectively. This modular system not only contributes to the building’s architectural diversity but also addresses structural requirements specific to each floor level [22].

The modular supports used in MuCEM—including the straight, Y-shaped, and N-shaped UHPC columns—were thoroughly evaluated through both laboratory and computational methods to ensure safety and performance under complex loading scenarios [22]. Full-scale physical testing was performed on these columns under off-centered vertical loads to simulate realistic conditions, including lateral sway and seismic-induced torsion. These tests demonstrated excellent stability and ductility, even under eccentric axial forces [23]. The UHPC’s inherent high compressive and tensile strengths were further enhanced with vertical post-tensioning, which minimized cracking and increased the columns’ energy dissipation capacity [9].

To supplement the physical testing, customized finite element models were developed to simulate seismic events, incorporating the columns’ complex geometries, material anisotropy from fiber alignment, and joint conditions [24]. These simulations demonstrated that the system would meet the performance targets for moderate to high seismic zones [25]. The findings were reviewed and validated by the project’s structural approval authority and confirmed to comply with Eurocode 8 standards for earthquake-resistant construction. As a result, MuCEM’s modular supports not only serve aesthetic and architectural purposes but are fully verified structural elements with high performance under seismic stress.

The columnand facade expressiveness of MuCEM’s building is enabled directly by the extraordinary properties of UHPC. Unlike conventional concrete, UHPC possesses higher flowability and compaction capacity and can, accordingly, be cast in intricate molds to precision and yield lacy geometries with very tight tolerances. Its elevated compressive and tensile strengths—achieved through fiber reinforcement optimized for these ends—make ultra-slender profiles possible without compromising structural soundness. This can be seen in the free-form Y- and N-shaped columns, whose unorthodox shapes resist different loads and help render the building sculptural. In the same manner, the lattice panels of the facade with their 80 × 70 mm sections and 3 m spans illustrate a material that has the ability to integrate lightness, transparency, and strength. These advancements would economically or structurally not be achievable using normal reinforced concrete, making the role played by UHPC in the realization of engineering precision and artistic creativity significant.

The variation between the three structure types—straight, Y-shaped, and N-shaped supports—is a personal interpretation ofarchitectural and engineering fit. While the geometries were mapped out with the architects’ and engineers’ inputs to define functionality and visual rhythm, optimization processes by computational means could more effectively enhance these forms [26]. In particular, methods such as the upgraded elitist genetic algorithm (SEGA) have been capable of providing satisfactory performance in optimizing column shapes that are non-conventional with multi-parameter constraints such as load capacity, material usage, and cost [27]. Such methods, unlike conventional parameter sweeps, enable simultaneous optimization for variables such as cross-section, prestressing, and arrangement in addition to respecting project constraints [28]. Use in free-form UHPC structures like those in MuCEM can not only be more efficient but also more resilient to lateral loads and external conditions. The useof such optimization software early in the design process could bridge the gap between expressive architecture and performance-based engineering [29].

3.3. Formwork and Assembly

The creation of each prefabricated part begins with the production of specially manufactured formwork. A model carpenter first crafts the desired shape out of wood. Using these wooden master molds, the negative form for the final concrete structure is created from glass fiber-reinforced plastic and stabilized by an external steel frame (Figure 8). To accommodate the post-tensioning process, empty pipes are embedded into the formwork for the subsequent insertion of tension cables.

Unlike conventional concrete, UHPC does not utilize loose reinforcement. To address UHPC’s inherent brittleness and enhance its tensile strength, metal fibers and polypropylene fibers are incorporated into the casting mixture. This concrete–fiber mix is then poured into the vertically positioned formwork, allowing gravity to align the fibers in the direction of the anticipated load on the supporting structure. This meticulous process ensures the structural integrity and performance of the UHPC elements in their final application.

3.4. Post-Tensioning over the Entire Height of the Building

To mitigate the orthogonal bending of columns under eccentric loads, post-tensioning is employed, enhancing the stability of the MuCEM’s structural elements. Originally, each column was to be post-tensioned individually on a floor-by-floor basis, necessitating cable inlets and outlets at both the foot and head of the columns and adjacent to the edge beams. However, to comply with the earthquake safety regulations (Eurocode 8), a more robust solution was devised.

In the revised implementation plan, continuous post-tensioning cables run from the basement to the roof, threading through three vertically aligned columns (Figure 9). The design of the column supports at their head and foot follows the principles established by Eugène Freyssinet, a pioneer of prestressed concrete. These supports, also constructed from UHPC, are designed as joints and are maintenance-free since they involve no contact between dissimilar materials.

The prestressing cables pass through these supports, integrating the columns with the 400 × 600 mm prestressed edge beams to form a cohesive, elastic structural framework. These robust yet flexible column supports can accommodate the continuous thermal expansion and contraction of the large, seamless ceiling slab and absorb sudden, horizontal impacts during seismic events. The effectiveness of the support details and the overall structural system was validated through rigorous experimental testing, each requiring individual approval. Additionally, specialized calculation software was developed in collaboration with the approval authority to accurately account for the complex shapes of the supports and ensure the reliability of the structure.

Beyond its structural and aesthetic roles, UHPC offers notable sustainability advantages. Its extremely low permeability and high compressive strength contribute to an extended service life, often exceeding 100 years with minimal maintenance. This long-term durability reduces the frequency of repairs and material replacement, thereby minimizing resource use and lifecycle emissions. Furthermore, the ability of UHPC to achieve structural performance with significantly thinner sections leads to a reduction in raw material consumption—especially cement, whose production is a major source of CO₂ emissions. As research shows, using UHPC can reduce embodied carbon by up to 30–50% over the life of a structure when compared to conventional concrete, particularly in applications where lightweight, durable elements extend service intervals and enhance structural efficiency. In the case of MuCEM, the use of UHPC for exposed and high-stress elements not only supports aesthetic goals but substantially reduces the building’s long-term environmental footprint [9,11].

The location of MuCEM in a seismic zone requires state-of-the-art techniques to ensure lateral stability and energy dissipation during potential earthquake forces. Here, UHPC played a vital role. The vertical post-tensioning system, which connects three vertically stacked UHPC columns with continuous cables, was designed to create a vertically integrated, elastic structural system. To reduce stress concentrations and permit lateral displacements, the column base and head supports were cast with UHPC and designed according to Freyssinet’s contact-free joints, which prevent rigid coupling between dissimilar materials. The joints dissipate shock and allow thermal and seismic movement without degradation [22].

To validate these strategies, each column arrangement was submitted to separate experimental testing under eccentric vertical loads, and simulations were run with custom software incorporating the non-linear behavior and geometrical complexity of the UHPC members. This hybrid design strategy—blending material high strength with elastic connection detailing—contributed to the robust seismic performance model according to Eurocode 8 demands and for possible extension to future UHPC-based structures in the same regions [10,23].

MuCEM is located in a zone of Seismic Zone 2/3 by Eurocode 8, having a design peak ground acceleration (PGA) between 0.2g to 0.3g. To resist such a seismic load, the UHPC support columns of the building were conceptualized as a fully vertical and continuous system using full-height post-tensioning and non-elastic stainlesssteel contact joints that allow for elastic energy dissipation and controlled displacement [15]. Simulation testing confirmed that the structural system would be able to accept seismic loads in the shape of up to 0.35g horizontal accelerations without exceeding deformation limits [23]. Experimental load tests on Y-shaped UHPC columns also confirmed their ability under combined off-center seismic-type and axial loading, both ductility and failure resistance, backing [22]. The results are in compliance with Eurocode 8 performance requirements and affirm the applicability of UHPC in earthquake-resistant design, especially when in combination with flexible connection systems.

3.5. Ceiling Slab and Column Connections

The ceiling slabs of the exhibition areas in MuCEM are a remarkable feat of engineering, measuring a seamless 52 × 52 m. These slabs are composed of 23mlong prefabricated ceiling elements, which are cast in a shear-resistant manner and integrated with 600 × 400 mm post-tensioned edge beams made of cast-in-place concrete. Initially, the competition design proposed ceiling panels made of Ultra-High-Performance Concrete (UHPC); however, due to economic constraints, C70 concrete was utilized instead, employing a prestressing process. This process involves pouring concrete around pre-tensioned cables placed directly in the formwork to ensure a robust shear-resistant connection.

A significant challenge in this construction was achieving the dimensionally accurate connection and precise force transfer from the cast-in-place concrete edge beams to the prefabricated UHPC columns, given the permissible tolerances of approximately 5 mm. The solution involved a UHPC bracket, which was only concreted as a connecting element after the columns had been fine-tuned to their final positions. Prior to installing the UHPC columns, workers cast the ceiling beams along with the edge beams to form a cohesive ceiling slab, supported temporarily by scaffolding structures (Figure 10).

After installing all the columns, thecables were tightened using winches located on the roof and ground floor, followed by pressing the cables and sheathing pipes together with a special cement mortar. Only once a force-fit connection had been securely established between the ceilings and columns were the temporary supports removed. The use of brackets to connect the columns to the edge beams also facilitated the geometric design of various structural variants, contributing to the lively, three-dimensional appearance of the structure.

In specific design variations, different connection methods were employed: In one scenario, the column runs past the ceiling beam uninterrupted, eliminating the need for brackets (Figure 11a). In another scenario, the entire cross-section of the column head is connected to the console (Figure 11b). In a third design, half of the column head’s cross-section is situated under the edge beam, with the other half supported by a shallower console (Figure 11c). These varied connections not only enhanced structural integrity but also contributed to the architectural dynamism of MuCEM.

For vertical elements, such as the tree-shaped columns, casting was performed with the molds oriented vertically, allowing gravity to assist in aligning the metal and synthetic fibers in the primary direction of stress. To accommodate post-tensioning ducts and connection hardware, precision-placed voids were included in the mold. The average geometric tolerance was limited to ±0.5 mm, necessitating the use of laser-guided surveying tools and manual micro-adjustments during installation.

During assembly, the prefabricated elements were joined using embedded stainlesssteel spikes and articulated connection brackets, which allowed limited degrees of movement to correct for site variation. The entire facade and column structure was dry-assembled off-site before final installation, ensuring that all the tolerances, thermal allowances, and structural interfaces met design specifications.

3.6. Continuous Network of Elements

The outer shell of the MuCEM building features self-supporting Ultra-High-Performance Concrete (UHPC) elements organized into intricate grid structures. The fabrication of these elements began with wooden master molds, which were used to create negative molds with sharp-edged cross-sections of 80 × 70 mm. The standard format for these elements is 3 × 5.80 m, with special formats employed at the edges to ensure a seamless fit (Figure 12a).

Three distinct patterns are meticulously arranged to form an apparently endless structure. This design gives the facade a continuous appearance, with minimal joints that make the individual elements discernible only upon close inspection (Figure 12b). The vertically aligned panels rest on the ground at the base of the facade, connected to the facade element above them via two embedded spikes each. To handle horizontal loads, diagonal stainless steel struts extend from the supports or posts of the glass facades, running over the surrounding ramps to the lattice elements.

Cross-shaped point holders, which allow for movement in two directions, secure two adjacent lattice elements at their vertical joints (Figure 12c), and in the case of edge elements, at their horizontal joints (Figure 12d). Each standard element is supported by four such struts. This articulated mounting system effectively prevents tension within the material, which could be caused by wind forces and temperature-induced expansion.

Horizontally mounted elements of the roof rest on a metal substructure, separated by elastic polyurethane supports. This substructure is mounted on the T-shaped UHPC supports located at the roof edge (Figure 13). This arrangement not only enhances the aesthetic appeal of the structure but also ensures its durability and stability under various environmental conditions.

While the MuCEM project is contextually specific—spawned from Marseille’s cultural environment and historical background—its use of UHPC demonstrates strategies that can be applied to other architectural and infrastructural projects. The prefabricationof modular UHPC supports, use of full-height post-tensioned columns, and development of ultra-thin but highly durable facade systems are all transferable strategies that can be applied to projects seeking material efficiency and sustainability over the long term. Additionally, UHPC’s versatility in accepting complex geometries without compromising structural performance opens up new possibilities for expressive architecture that fulfills environmental performance goals. These techniques can be scaled and adapted to suit public buildings, bridges, museums, and high-performance facades in diverse urban or environmental contexts. MuCEM, thus, becomes an unparalleled landmark and prototype for integrating UHPC into resilient, architecturally groundbreaking design worldwide.

Thermal expansion and contraction are critical considerations in a structure like MuCEM, which includes large, slender UHPC elements directly exposed to sunlight and coastal climate variation. UHPC has a relatively low thermal expansion coefficient (~11 × 10⁻⁶/°C), offering greater dimensional stability than conventional concrete [24]. Still, to ensure structural integrity over time, the building’s UHPC lattice and roof systems were designed with cross-shaped point holders and articulated stainlesssteel struts that allow for multi-directional movement. These connectors prevent internal stress accumulation by enabling slight sliding and rotation between adjacent panels in response to temperature changes [30]. Additionally, the continuous post-tensioning system in the columns and edge beams enhances elasticity, helping the structure absorb thermal loads without cracking or deformation [31]. These strategies reduce the risk of fatigue or failure due to daily thermal cycling and ensure the long-term durability of MuCEM’s façade and structural framework.

Based on international field data and durability assessments, UHPC exhibits a service life exceeding 100 years with maintenance intervals 60–80% less frequent than conventional concrete. Studies show negligible degradation in compressive or flexural strength after over 10,000 freeze–thaw cycles, and chloride penetration depths of <1 mm after 1000 h of exposure, making it ideally suited for structures in coastal zones. In the case of MuCEM, this translates to significantly reduced lifecycle costs and ensuresthelong-term preservation of both structural integrity and visual appearance with minimal intervention [9,32,33].

4. Conclusions

The Musée des Civilisations de l’Europe et de la Méditerranée (MuCEM) marks a pivotal moment in contemporary architecture, where material innovation, cultural heritage, and sustainable construction converge. The integration of Ultra-High-Performance Concrete (UHPC) was not incidental, but a strategic choice aimed at addressing multiple project objectives: enabling expressive architectural forms, enhancing structural performance, and promoting long-term environmental sustainability.

Each major design element—from the elegant pedestrian bridge to the modular supports and the delicate lattice facade—demonstrates how UHPC enabled a balance between form and function, history, and modernity. These features not only achieve aesthetic distinctiveness but also embody resource efficiency and resilience, vital for structures expected to endure both time and environmental pressures.

The construction of MuCEM also reveals the transformative potential of UHPC in modern engineering. Innovations such as full-height post-tensioning, fiber alignment through gravity casting, and precise connection detailing underline the complexity and rigor of the project. These engineering strategies helped reduce maintenance demands, improve seismic performance, and extend the building’s lifecycle—all critical aspects of sustainable design.

Ultimately, MuCEM illustrates how a high-performance material can become a medium for architectural storytelling, environmental responsibility, and structural ingenuity. It stands as a forward-looking example of how public architecture can embrace sustainability not only through energy metrics, but through material choices that align beauty, function, and durability.