A Study of Prestressed Earth

Caleb Adams, Fernanda Loyola Cardoso and Isabelle de Metz

The project begins with an exploration of the Kiln Tower for the Brickworks Museum by Boltshauser Architekten. Designed as a contemporary reinterpretation of the site’s industrial heritage, the tower serves as both a landmark and an exhibition structure for the museum. Our interest, however, focused specifically on how the project investigates rammed earth as a contemporary structural system through prefabrication and vertical prestressing.

Kiln Tower for the Brickworks Museum in Switzerland by Boltshauser Architekten from 2021. Source: Archello

Earth blocks in tension. Source: Arch Daily

More specifically, the tower utilizes steel tension rods to compress stacked earthen blocks, transforming them into a 9-meter-high, earthquake-resistant structure. By placing the earthen elements in constant compression, the system overcomes earth’s inherent weakness in tension while enabling a tall, stable, and fully reversable building assembly.

In an attempt to parallel the intricacy of this construction system, our team sought to create an earthen, modular prototype of the tower to explore the possibilities of earth and its compressive strength. To achieve this, our team began by experimenting with mixtures of three key ingredients earth, clay, and sand, using different ratios to produce bricks measuring 3”x4”x6” inches. A wooden formwork system was first constructed, along with a hand-made ramming tool fabricated from plywood to begin ramming the earth together. The proportions of the earth, clay, and sand were varied as the bricks were layered vertically in order to create visible striations throughout the assembly.

Next, we cut plywood rectangles matching the exact dimensions of the bricks to sandwich the central units together. Additional plywood plates, extending one inch beyond the top and bottom bricks, were then added to cap the assembly. Five bricks were stacked vertically, allowing us to drill a #10 tension rod through the entire length of the prototype. Tension was then achieved by tightening a nut and washer at the top of the rod, compressing the stacked earthen blocks together and replicating the prestressing strategy used in the original tower.

The final prototype successfully stacks five compressed earth blocks, demonstrating the structural viability of the prestressing strategy. The assembly can serve as both a vertical wall and horizontal ceiling/lintel condition. Our investigation turned towards its potential as a ceiling or lintel element, since achieving horizontal spans in earthen construction is a known difficulty due to the material’s poor tensile performance. We tested the model as a simple beam supported at two end points, and as a double cantilever supported in the center, and observed how the prestressed compression allows the earth to resist gravity loads that would have otherwise caused failure.

This study establishes a foundation for further investigations and possibilities of this novel system. There could be further testing of the module’s maximum load, determining the ideal span to depth ratios. Beyond the individual module, there’s an opportunity to explore how these modules could interlock adjacently to form a seamless ceiling or floor diaphragm. The tie rods could potentially pass through the bricks, or the plywood end plates elements might be redesigned to serve as structural joinery.

Finally, the long-term interaction between the wood, metal, and earth offers a compelling study in differential weathering. The accelerated erosion of earthen components will affect the tension of the steel rods, and together with the slower erosion of the wooden plates may affect the strength of the overall system over time. However, the different rates of erosion may create beautiful aesthetic contrasts.

May 11, 2026May 11, 2026

Prototyping Modular Rammed Earth Furniture

Timeline

Spring 2026 – Summer 2026

Project Description

This project consists of a series of experiments aimed at prototyping a design for a rammed-earth coffee table.

Intended to adhere to a series of constituents concerning weight, modularity, and color, this rammed earth prototype was designed such that it could be disassembled into smaller, more manageable components. These constraints led the designers to a prototypical model consisting of cylindrical blocks weighed down by a raw stone tabletop, ensuring that each module remains in compression and does not shift. The blocks themselves are rammed into a formwork, creating handles for carrying, easing transportation. Each module weighs ~35lbs and features a mixture of pigments that create a customizable gradient.

Ratios and Gradients

This project also sought to examine the aesthetic sensibilities of rammed earth as a construction material for furniture. Prototyping rammed-earth furniture necessitated extensive studies concerning the mixture of different soils and pigments to create colorful gradients for each module.

Rough, rocky earthen qualities are achieved through a basic mixture of soil from varying regions, alongside ~15% sand, ~20% gravely clay to provide enrichment. These mixtures were then enriched with increasing quantities of pigment (including charcoal and iron) to allow each rammed layer to take on a more saturated color during the production of each earthen module.

Form-work and “Molds”

The contents of rammed earth require a formwork to take on the desired shape after settling. The foundation of this formwork, chosen for its size, shape, and flexibility, was a concrete form tube, often known by its brand name of Sonotube. These form tubes come in a variety of different sizes, meaning that the techniques we developed to create these rammed earth pieces can be transferred based on the desired scale.

If we had just used the sonotube, the outcome would simply be a cylinder. The next step was incorporating the physical additions that allow for handling and modularity. Utilizing 3d prints as a negative, mixed in with conventional building techniques such as cut and shaped wood, inserts were created that fit into the sonotube to create indents and features in the otherwise normal cylinder. These included handling grips, for ease of movement of the final product, to central cavities, reducing the overall weight, and even attempts at projections on the top surface to fit right into the handling grips, to help with positioning and balance of the pieces once put together.

May 11, 2026May 11, 2026

Project Lithos — (3d Printed Form Work)

Group Member: Chuhan Zhao, Yiluo Li

We started from the Augsburg Environmental Education Center, where rammed earth is used as an interior wall. In that project, we observed that different materials—such as wood or concrete—are typically placed next to or on top of the rammed earth. In other words, the materials remain separate, and their interaction mostly happens at the surface.

Hess / Talhof / Kumierz Website: Umweltbildungszentrum
Augsburg – Transition from Botanical Garden

Hess / Talhof / Kumierz Website: Umweltbildungszentrum
Augsburg Interior

What interested us was what happens if this relationship changes.

So our main question became:

What happens when materials are not adjacent to rammed earth, but embedded within it?

Instead of treating rammed earth as a pure, monolithic material, we began to think of it as a mass that can integrate other systems and become a composite condition.

To test this idea, we first made an initial model of a curved rammed-earth wall with a grid inserted into it. This allowed us to explore the relationship between a heavy, continuous mass and a lighter, secondary system. Rather than assigning a fixed program, we understood this as a spatial condition defined by material interaction.

From there, we moved toward a smaller and more controlled scale and developed the final objects you see below.

This object is not intended as a product or a finished design, but as a material prototype.

It consists of a rammed earth mass with an embedded element, and a central cavity that holds a light source. The inserted ring acts as an interface within the earth mass, and the light passes through this composite condition.

What becomes important here is not the form itself, but how light interacts with the material. The light reveals the thickness, the texture, and the relationship between the earth and the inserted element.

At this scale, we are able to control the variables more precisely and focus on how rammed earth behaves when it is no longer a single material, but part of a system.

So rather than designing a lamp, we are using light as a way to understand how a monolithic material can become composite, and how that affects spatial and material experience.

May 11, 2026

Inlaid Earth Artifact

The project begins with two references: the earthen wall of the Valéria Cirell House and Studio Moffitt’s prototype-based model approach. While the Valéria Cirell House demonstrates how rammed earth can function as both structure and material expression, Studio Moffitt’s work proposes a different way of understanding architectural models, not as literal representations of buildings, but as prototypes that isolate and test specific architectural ideas through fabrication and abstraction.

Valéria Cirell House

Studio Moffitt’s prototype-based model

Inspired by these two approaches, the project does not attempt to reconstruct the original house through detailed representation or structural replication. Instead, it extracts the tectonic and material logic of earthen architecture and reorganizes it into an abstract wall prototype. The project therefore operates simultaneously as a fabrication experiment, a material study, and an architectural interpretation.

The physical prototype is constructed using rammed earth techniques. Clay is mixed with different fibers and aggregates to form the primary body of the wall, while various stones are embedded within the surface. Through layering and compaction, the materials are compressed into a dense monolithic mass. Rather than functioning as decorative additions, the embedded stones become integrated into the wall itself, producing a textured surface that emerges directly from the internal material composition.

Material testing became an important part of the process. Different soils, granular materials, fibers, and stone fragments were explored in order to understand how texture, density, and structural stability could coexist within a single fabricated object. The goal was not to display isolated samples, but to investigate how multiple unstable materials could be transformed into a cohesive architectural system through compression and fabrication.

Beyond material experimentation, the project also explores a process of architectural abstraction. Instead of reproducing the original earth structure in detail, the prototype reinterprets it through a simplified geometric language. The project is interested in how modern architectural abstraction can translate primitive construction systems into reduced formal objects. In this sense, the prototype does not simply represent the original architecture, but reconstructs its essential relationship between mass, material, and structure in a contemporary form.

The wall therefore becomes more than a fragment of architecture. It operates as an artifact that records the interaction between material behavior, fabrication techniques, and formal abstraction. Texture is not applied afterward, but generated through the internal logic of layering, compaction, and embedded matter. The prototype ultimately positions rammed earth not only as a historical construction technique, but as a contemporary architectural language capable of integrating material expression, fabrication, and abstraction into a unified system.

May 11, 2026

From Waste to Earth——Experimental Material Test of Compressed Earth Block

Group Member: Yuxin Chen & Yufan Jiang

This project explores the potential of compressed earth blocks as an experimental architectural material infused with organic waste additives.

Inspired by the textured earthen surfaces of the Beijing Teahouse by Kooo Architects, the research began with testing different types of tea leaves and later expanded to include coffee grounds and plant fibers as additional material components.

Through a series of hand-crafted molds and compression tests, the study investigates how these organic materials influence the color, texture, density, strength, and tactile qualities of soil bricks.

Beyond material testing, the project also explored the architectural application of the bricks through the fabrication of a full-scale 1:1 prototype and a 1:4 mock-up model. These models were used to study brick geometries, assembly methods, and the spatial and atmospheric potential of the material as an interior wall finish.

By combining waste materials with traditional earth construction techniques, the project examines new possibilities for sustainable material reuse while emphasizing the relationship between craft, material experimentation, and architectural atmosphere.

May 9, 2026May 9, 2026

Detail Study & Modeling Of Rammed Earth House

Section Model of Rammed Earth House Designed by Tuckey Design Studio

Project Introduction

Group Member: Wentao Lyu , Tianwu Zheng , Zuohao Qiu

This research explores the construction logic and tectonic characteristics of rammed earth architecture through precedent analysis, detail studies, and physical model experimentation. The project focuses on the relationship between rammed earth walls, timber structures, openings, and material connections.

A 1:10 sectional model and a series of material tests were developed to study fabrication methods, construction details, and the integration of different building systems within rammed earth construction.

Research Framework

01 — Fabrication Process of Rammed Earth Walls

Study of rammed earth wall construction, including soil mixture, layering, moisture control, and compaction methods.

02 — Connection Logic Between Earth and Other Systems

Investigation of how rammed earth walls connect with timber structures, roof assemblies, foundations, and waterproofing details.

03 — Integration of Openings within Load-Bearing Walls

Analysis of window openings and structural transitions within thick rammed earth wall systems.

Modeling & Material Experiments

Sectional Model

Development of a 1:10 sectional model combining rammed earth walls, timber framing, and window details to study tectonic relationships and construction sequencing.

Material Testing

Material experiments focusing on soil ratios, wetness testing, compaction techniques, and layered rammed earth fabrication at model scale.

May 7, 2026

PROGRAMMED DECAY: DESIGNING INTENTIONAL EROSION IN EARTHEN ARCHITECTURE

This erosion study began with an observation of the oldest sections of the Great Wall of China, where layers of straw and mud eroded at different rates over thousands of years, revealing soft, undulating patterns beneath the surface. Rather than seeing erosion as decay, the project explores it as a design tool. Through a series of material experiments, clay bricks were cast with embedded elements—including sugar, salt, wax, leaves, and wood—that dissolve, melt, burn, or persist over time. Some materials outlast the earthen surface, while others disappear quickly, leaving behind voids and textures. The work imagines earthen architecture as something dynamic and time-based, where patterns slowly emerge through weathering and environmental change.

Catalina Lusk

May 7, 2026May 7, 2026

Chunk Model Study of Nursery School at Roches de Condrieu

Group Member: Zhixuan Zhou (MAAD) & Yushi Gan (MAAD)

We constructed a 1:1 scale model of a rammed earth wall corner for the Nursery School at Roches de Condrieu project. Our objective was to explore the actual construction process involved. The region where this project is situated is characterized by traditional local rural architecture built using rammed earth.

We fabricated the rammed earth molds using a combination of plywood and 3D-printed components. We then proceeded by ramming a layer of earth, followed by pouring Rockite cement; this process was repeated three times to complete the final model.

Although traditional construction methods might not typically incorporate modern techniques such as 3D printing, our fabrication process proved instructive, allowing us to gain valuable insights into the integration of two distinct construction methodologies: rammed earth and poured casting.

Project Archdaily

Architect Website

April 7, 2026

Dachverband Lehm (Organization)

Dachverband Lehm is a German-based organization, established in 1992, specializing in earthen construction, particularly the use of rammed earth (Lehm in German) as a modern, sustainable building material. The company focuses on reviving traditional earth-building techniques while integrating contemporary engineering and architectural practices. Based in Germany, Dachverband Lehm works closely with architects, designers, and builders to create structurally sound and aesthetically refined rammed earth walls for residential, cultural, and commercial projects.

The organization emphasizes the environmental benefits of earth construction, including low embodied energy, recyclability, and the use of locally sourced materials. Their work demonstrates how rammed earth can meet modern building standards while maintaining a strong connection to natural materials and regional identity.

Dachverband Lehm maintains an extensive online resource through their website, earthbuilding.info. The site offers comprehensive information on traditional and contemporary earthen construction techniques, material selection, and design considerations. It also features educational content, including training programs, workshops, and vocational courses for professionals and enthusiasts interested in sustainable building practices. Visitors can explore international research initiatives, case studies, and examples of earth architecture, along with guidelines, standards, and regulatory information that support the safe and effective use of rammed earth in modern construction.

April 7, 2026April 7, 2026

Zawiyyet Al Mayyiteen, the City of the Dead

Zawiyyet Al Mayyiteen (also known as Zawyet el-Sultan or Zawyet el-Amwat) is located on the southern edge of the city of Minya and is situated between the Nile river and desert cliffs to the East. Often called the “City of the Dead,” it is considered one of the largest cemeteries in the world, measuring nearly 4 kilometers long and 300 meters wide, covering roughly 1.2 square kilometers. Zawiyyet Al Mayyiteen is not just a modern cemetery; it is built atop layers of ancient history spanning nearly 5,000 years.

The cemetery is 4 kilometers long and 300 meters wide and is situated between the Nile and Desert Cliffs.

The site is easily identifiable by the repetition of small scaled domes made of mudbricks and plaster. Each domed mausoleum belongs to a different family and ancestral lineage. The highly concentrated sea of domes is easily read as a single web structure or pattern resembling the geological landscape, its growth seems fairly gradual and responsive to the site.

Looking at the Nile from within the cemetery.

This style of burial is traditional for the region, used by both the local Muslim and Coptic Christian communities, making it a rare site of shared funerary heritage.

During religious holidays and annual festivals, thousands of people from Minya travel to the site to visit their ancestors, often staying in the mausoleums to share meals and offer prayers.

Mudbrick and plaster in various conditions.

The unique aesthetic of the domes has long inspired artists and photographers. The nearby village is also home to the museum of the famous Egyptian folk artist Hassan el-Shark, whose colorful paintings often depict the daily life and spiritual traditions of the Minya region.