Brick on Mars

tahanson43206 · 2025-11-12 19:41:53

This topic in Science, Technology and Astronomy celebrates the humble brick.

Post #3 contains a summary prepared by Google, showing a snapshot of the history of bricks over 10,000 years on Earth.

The topic is inspired by posts of Calliban, who has described brick that might be made on Mars with superior strength, thanks for the abundance of iron in the regolith on Mars.

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tahanson43206 · 2025-11-12 19:42:46

This post is reserved for an index to posts that may be contributed by NewMars members.

Index:
Post #3: An overview of brick, prepared by Google.

Post #4: Calliban with sketch of a dome build of brick with a spiral roadway for construction and stability
https://newmars.com/forums/viewtopic.ph … 41#p235441

Many worth while posts deserve mention here ... at present we are not staffed up to update indexes properly.

Here is an update for Post #42: http://newmars.com/forums/viewtopic.php … 11#p236011
In this post Calliban describes the procedure to make green bricks with compression, and then baking them with a reactor.

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tahanson43206 · 2025-11-12 19:44:49

Inspired by a post by Calliban, describing a kind of brick that might be made on Mars, I asked Google to write a summary of the history of Brick.

when were bricks first used by humans on Earth?
AI Mode
When and How Were the Bricks In Your Old House Made?
Humans first used bricks around 10,000 to 9,000 BCE. These early bricks were sun-dried mud bricks, often mixed with straw, and were found at archeological sites like Jericho. Later, around 4000–3500 BCE, the technique of firing bricks in kilns to make them more durable was developed in Mesopotamia.
~10,000–9,000 BCE: The earliest known bricks were mud bricks, created by shaping mud with a binder like straw and drying them in the sun.
~7,000 BCE: Archeological evidence places the use of bricks at this time, with early examples found near ancient Jericho.
~4000–3500 BCE: The innovation of firing bricks in kilns occurred in Mesopotamia (modern-day Iraq). This made bricks much stronger and more resistant to weather.
Later Developments: The use of fired bricks spread throughout the ancient world. The Romans, for example, used standardized fired bricks extensively, and later, during the "Brick Gothic" period, fired bricks became the primary building material in Northern Europe where stone was scarce.

This topic is available for posts that might help an entrepreneur to plan and create an entire industry on Mars.

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Calliban · 2025-11-13 19:11:18

The image below shows how I think we will build brick domes on Mars.

The inner black lining is a parabolic dome that would be constructed from Class A engineering bricks. Regolith covers the dome and forms a spiral Ziggurat. This allows a spiral road to wind around the structure until it reaches the top.
https://en.wikipedia.org/wiki/Ziggurat

The stepped structure shown in my sketch is exagerated. Likely, the retaining wall behind the road will be no more than 1m high, so each spiral layer as shown in the drawing would be 1m high. This avoids any significant load concentrations that could result in buckling instability. The road will wrap around the structure over 100 times before reaching the top. We would build the berm incrementally around the parabolic dome as it is assembled towards its apex. This allows assembly robots easy access to the work surface by running up the spiral road. It also avoids the need for formwork inside the dome, as robots can climb up the regolith berm to get to the work surface. With each new metre added to the dome, regolith would be piled around it and the spiral road will be extended once around the structure. In this way, the only materials needed are brick, stone, graded regolith and a binding cement for the bricks.

The dome shown here has a diameter of 200m (650'). This gives an internal land area of 3.14 hectares. The dome itself can be quite thin, as it is really acting as a retaining wall to prevent compacted regolith from crumbling inward. We would need a minimum of 400,000 tonnes of graded regolith to build the berm. This is the amount needed to balance an internal pressure of 50KPa under Martian gravity over an area of 3.14 hectares. Moving and compacting this much regolith is no small task. If we processed 1100 tonnes per day, it would take about 1 year to build the structure. Assuming a dome thickness of 7.5cm (standard width engineering brick) we would need ~15,000 tonnes of engineering bricks. That is 41 tonnes per day × 1 year. That is about 12 cubic metres of bricks per day. I think we could do that in a modest sized brick oven.

I anticipate that the dome would contain an extremely dense urban district. This will consist of very narrow pedestrian streets lined with terrace houses and shops. Rather like the Fez medina. To get the most use out of our dome, I anticipate that the internal town will be built on three levels. The lowest level will consist of a network of subsurface tunnels and chambers. This would contain functional infrastructure (water delivery, sewage removal and treatment, electric power delivery), as well as small scale industry, inventory storage and any other functions that don't need to take place in the buildings above. Next will be town itself, a dense network of terrace buildings designed to resemble a mediaeval town. These would be limited to 5 floors high, to preserve the human scale of the city. Finally, the top level will be the flat roofs of the buildings, which will be landscaped as a continuoys greenspace, with footbridges running over streets.

How many people would live in the dome?

Last edited by Calliban (2025-11-13 20:17:51)

tahanson43206 · 2025-11-13 20:12:05

Calliban brings a unique combination of talents and skills to this forum. In post #4 Calliban showed us a possible habitat design that might be constructed entirely from native materials, assuming a supply of sufficient energy to carry out the needed operations.

I asked Gemini (Flash 2.5) to evaluate the proposal. It suggested a bit more mass in the regolith layer, and complained that the one year construction time table seemed aggressive. All in all, it seemed to me that Calliban's proposal stands up well.

Overall, the proposal is highly viable from an engineering physics standpoint, though the logistical timeline is extremely aggressive.
1. Structural Viability: Pressure Balance
The central principle of using the regolith berm to counteract the internal pressure of 50 kPa (which is 0.5 bar) is correct. This design puts the dome structure under compression from the overburden, which bricks handle extremely well, rather than tension from the internal atmosphere.
Pressure Calculation Breakdown
For a 200 m diameter dome (r = 100 m), the total area is A is approximately 31,416 m^2.
[] Total Uplift Force: F_int = Pressure x Area = 50,000 Pa x 31,416 m^2 is approximately 1.57 GigaNewtons (GN). [] Force Generated by Proposed Mass (on Mars): Assuming Martian gravity (g_Mars is approximately 3.72 m/s^2): F_reg = Mass x g_Mars = 400,000,000 kg x 3.72 m/s^2 is approximately 1.49 GN.
Required Mass for Balance: To generate the 1.57 GN required force, the actual mass needed is: M_req = F_int / g_Mars = 1.57 GN / 3.72 m/s^2 is approximately 422,257 tonnes.
Conclusion on Mass: The estimate of 400,000 tonnes is close, but the structure would require approximately 422,000 tonnes of compacted regolith to achieve a purely hydrostatic vertical balance. This 5% shortfall is minor and easily accounted for by adding a small safety margin to the regolith depth.
Using an average compacted density for Martian regolith (~1,500 kg/m^3), this mass translates to an average regolith depth of about 9 m over the dome's surface.
2. Materials and Stability
Class A Engineering Bricks Your material choice is excellent. Class A engineering bricks on Earth are specified for high compressive strength (>= 125 N/mm^2).
[] Strength: The compressive strength of Class A bricks is orders of magnitude greater than the compressive stress (0.05 N/mm^2) that would be placed on the dome by the 9 m of regolith. [] ISRU Feasibility: The main challenge is the In-Situ Resource Utilization (ISRU) needed to produce them. The "binding cement" is particularly challenging, as it would likely require a sulfur-based, polymer-based, or sintered-regolith binder instead of traditional, water-intensive cement.
Ziggurat Design and Buckling The stepped Ziggurat design with 1 m retaining walls is highly effective for stability and buckling mitigation.
[] Buckling: By building the regolith berm incrementally around the dome as it rises, the bricks are constantly kept under a stable, external compressive load. This continuous support, combined with the spiral retaining walls to manage lateral shear and sliding forces, significantly reduces the risk of global instability. [] Load Concentration: The 1 m vertical rise per layer prevents excessive soil shear/creep and distributes the regolith load more evenly against the parabolic dome, successfully avoiding significant load concentrations.
3. Construction Methodology and Logistics
Incremental Assembly The incremental construction method is the most innovative and practical aspect of the proposal.
[] Formwork Elimination: By leveraging the regolith berm as continuous external formwork, you eliminate the need for colossal and complex internal scaffolding, which would be extremely difficult and resource-intensive for a 200 m dome. [] Robot Access: The spiral road provides essential, continuous access for automated robots to place the next course of brick and apply/compact the next layer of regolith. This is a very elegant solution to the construction logistics challenge.
Timeline Challenge The timeline of 400,000 tonnes in one year (approximately 1,000 tonnes/day) is highly ambitious. While low Martian gravity allows equipment to move larger loads, maintaining a 24/7/365 operational tempo for mining, processing, transporting, and compacting regolith at this scale would require a highly robust, automated, and redundant fleet of heavy machinery. The timeline is an operational challenge rather than a fundamental flaw, and should likely be extended to account for manufacturing and maintenance downtime.
The engineering consideration for managing the lunar and Martian regolith in large-scale construction is discussed in this resource: Lunar Engineering 101 - Dust and Regolith.

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Calliban · 2025-11-13 20:43:45

If the bricks are quite smooth, then a thin layer of epoxy glue could be used to bond them. If we assume a brick height of 10cm and a 1mm layer of epoxy glue, then we would need about 50 cubic metres for the whole dome. The glue would weigh about 50 tonnes. There are three potential challenges that I can see:

(1) As the dome rises, the work surface curves inwards. Beyond about 1/3rd of the way up, each new layer of bricks would need to be held in place whilst the glue sets.
(2) Mars is cold compared to most environments on Earth. Glue would be extremely stiff at temperatures <0°C. Setting time would be long, if indeed it sets at all. We may need to apply resistance heaters to keep the bricks and glue warm while the glue sets.
(3) Mars has an atmosphere with non-negligible pressure, which is a strong advantages over the moon. However, epoxy monomers are quite volatile. Will evaporation negatively impact the glue?

Assuming we can solve these problems, epoxy glue looks like the best approach. We could potentially produce a fine paste of epoxy glue and martian fines as a cement. That way, we can reduce the required mass of glue still further.

Last edited by Calliban (2025-11-13 20:47:45)

Calliban · 2025-11-14 16:40:42

The attached image shows a possible plan view of the town built beneath the proposed 200m diameter brick dome on Mars.

The red lines indicate the walls of individual buildings. The black shaded areas are roads, squares and the agora (in the centre). All roads are entirely pedestrian spaces. The two ring roads have a width of 2m for pedestrian traffic. The two straight roads that cross the agora have a minimum width of 3m. The streets widen at intersections. These are natural meeting places and will likely be the location of cafes, with extra seating spilling out onto the street.

The agora is a circular paved area some 50m in diameter at the centre of the town. Most days this will contain overspill outside seating from restaurants and bars. It will also host open air markets, Christmas events, theatre performances and is large enough to accomdate the entire population for town meetings.

All buildings are coloured green. This denotes the presence of roof gardens. Every building will host roof garden space. This will all be connected to form a continuous landscape, with foot bridges connecting all blocks above street level. This is important, because the street level of the town is extremely confined, with almost all of space taken up by buildings. The roof garden landscape provides an open green space that is open to all by ascending a spiral staircase from the street or from within buildings. These garden spaces will be places for recreation. This limits the stress of living within an otherwise crowded environment.

The buildings at the outer edge of the dome are large structures. They will include such things as sports facilities, gymnasium, schools, cinema, university departments, hotels, government buildings, public bathhouses and overspill accomodation. These will be constructed right up against the edge of the brick dome. The inner districts consist of smaller buildings. These will include terrace houses, as well as shops, bars, cafes and restaurants.

The whole town will be very densely inhabitated, due to the cost of constructing the dome. Houses will be small in footprint, but also tall. Flats may also be located above commercial premisses. How many people could live in this town? The medina in Fez, Morroco is a pedestrian city with a floor area ratio of about 1.5. It's population density is about 550/hectare. Our Martian town will have structures constructed on about 80% of internal land area, to a height of 5 floors. So floor area ratio is about 4. I will therefore conservatively assume about double the population density of the Fez medina. The area under the dome is 3.14 hectares, suggesting a population limit of some 3,500 people. The inclusion of underground spaces in addition to the roof garden, allows these people to spread out some more. It might be tolerable for some people to live in underground apartments, if they can climb a set of stairs into the town when they need open space.

tahanson43206 · 2025-11-15 17:25:26

For SpaceNut ... this topic is about Brick on Mars.

This topic is NOT about Brick on Earth.

It seems to me that Calliban has tried to answer all your objections before you asked them.

Which of his answers was not to your satisfaction?

What else would you like to know?

This topic is an opportunity to build a store of knowledge. You have identified knowledge elements that you think could be profitably added to the topic. Please make a list of knowledge we do not presently possess.

That way Calliban can start working on the specific items you identify.

I'd like to point out that you have created the start of a helpful list.

It might even be possible to implement your suggestion of creating a Martion test cell to prove that the solutions Calliban proposes will work. The only thing we cannot control is gravity, and I doubt gravity is much of a factor in brick laying.

The variables that seem likely to be of concern include materials for the bricks themselves, mortar or glue to hold the bricks together, the atmosphere in which bricks would be laid, temperatures and pressure.

Please create a list of these and other items you'd like Calliban to address.

And please ** do ** feel free to ask the AI to help. The AI knows more than any of us humans about Mars, because it has access to ** all ** of human knowledge, which we humans do NOT.

However, before you ** publish ** your list, please be sure you have read ** every ** word that Calliban has already written on this subject. It might turn out that he has already addressed some of your concerns.

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Calliban · 2025-11-16 11:45:55

The problem with building large and thin masonry domes, is not the strength of the materials, it is stability. Prior to pressurisation, the dome will be subject to external forces from the overburden. If these are too high, they will buckle the dome inwards, even if the crush strength of the dome is never exceeded. The critical external pressure that could result in buckling instability for a sphere or hemisphere, is given by:

Where:
Pcr = critical external pressure for onset of buckling (Pa);
E = Young's Modulus (Pa);
v = Poisson's Ratio;
t = dome wall thickness (m);
R = Dome radius (100m).

For Class A engineering brick, Poisson's Ratio is 0.15 - 0.25. I have taken an average value of 0.2. I could not find a value of Young's Modulus for hard engineering bricks. This site proposes a value of 20GPa for brick generally.
https://www.engineering.com/youngs-modu … the-brick/

We will be putting enough overburden on the dome to impart a 50KPa external pressure. This will be sufficient to counteract internal pressure when the dome is fully pressurised. Prior to pressurisation, during construction, there will be a net inward pressure of 50KPa acting downwards. Maximum effective pressure will be experienced at the dome apex. This is where buckling is most likely to occur.

Solving for the known variables, gives a minimum stable value of t of 14.56cm. The mortar between bricks will also effect youngs modulus of the structure. We are planning to use epoxy resin to glue the bricks together. However, assuming that individual bricks are polished, only a very thin layer (0.1mm) of epoxy need be applied to bond them. So the effect of the mortar in this case will be minimal. With this in mind, for a 200m diameter dome, wall thickness should not be less than 14.56cm. A thickness of 20cm allows for some margin of safety.

Of course, the dome presented here is not a perfect hemisphere. It is parabolic, which allows downward compressive forces to be absorbed with reduced shearing stress within the structure. This reduces the risk of buckling. In addition, Martian regolith is known to possess adhesive properties due to its high iron oxide content. Indeed, compressing regolith fines in a mold would produce a reasonably strong ceramic. This gives reason to expect that any compacted regolith layer would tend to redistribute load around the dome, reducing the downward pressure acting on the apex. These factors tend to suggest that the calculated value of minimum safe thickness is conservative and a 20cm dome thickness will be more than adequate to ensure structural stability.

The ratio of t/R is constant for all values of R with the same materials properties. This means that a dome with 50m radius required a 10cm minimum brick wall thickness. Likewise, a 500m diameter dome would require a minimum wall thickness of 50cm.

Last edited by Calliban (2025-11-16 11:53:48)

tahanson43206 · 2025-11-16 22:04:03

This post is a follow up on #14 by SpaceNut .... as i read #14, it is a call / request invitation for a rendering of the interior of Calliban's Town/Village dome concept.

I decided to see what I might be able to achieve by talking to Gemini (Flash 2.5) which is greatly improved over initial versions, but less advanced than the top-of-the line paid version. In the session we exchanged views until we arrived at a resolution that I think comes reasonably close to capturing what I understand of Calliban's vision. The post below is cast as an outreach to Calliban, asking for information that might be used to create a drawing that SpaceNut might enjoy.

? Collaborative Findings: Martian Habitat Construction (Brick Dome)
********
To: Forum Engineer
From: Moderator/Gemini AI
Subject: Sequencing, Scaffold-Free Build, and 3D Visualization Request
Introduction and Acknowledgment
We have had a very productive conversation regarding the large-scale Martian brick dome concept. Our discussion focused on the practicalities of construction sequencing, specifically addressing the constraint of no interior scaffolding and leveraging In-Situ Resource Utilization (ISRU).
We fully endorse the foundation of your design:
* Use of high-compressive-strength Martian Class A Bricks for the primary pressure wall.
* Protection via a thick outer layer of packed regolith for radiation shielding and external pressure balancing.
* Targeting the structural requirement for a 0.5 bar internal atmosphere
********
Revised, ISRU-Centric Construction Sequence
We've refined the final stages of construction to be more efficient and purely Martian-resource focused, using the concept of a corbelled or self-supporting dome built from the exterior.
1. Wall Construction: The dome wall is built progressively from the exterior, potentially using a Ziggurat-like stepped ramp for worker access and material delivery.
2. Cap Lift Method: The pre-assembled cap is lifted and secured into the dome's apex.
* Lifting Gas: Temporary buoyancy assistance can be achieved using easily harvested and discarded CO₂ (from the Martian atmosphere) within a lifting balloon/fabric system, coupled with exterior cable/crane assistance.
* Atmosphere Sourcing: All final gases (O₂, N₂, Ar) for the 0.5 bar atmosphere are assumed to be generated entirely by ISRU plants on Mars, eliminating the need to import atmosphere components from Earth.
3. Pressurization: Once the cap is sealed, the habitat (starting at a near-vacuum) is directly filled with the final O2 N2 Ar mixture to the required 0.5 bar pressure.
********
Request for 3D Visualization Data
To generate a compelling and accurate 3D image of the interior of this village/town-sized dome, our AI image generator needs the functional equivalent of your 2D sketches described in text. Since we cannot accept image uploads, please provide the following scale and feature details:
* 1. Scale & Dimensions:
* What is the **Diameter** (or length/width) of the dome's base?
* What is the maximum **Height** of the dome (from floor to cap)?
* 2. Wall Structure Detail:
* What is the intended **Thickness** of the inner brick pressure wall?
* How thick is the total **Regolith Shielding Layer** (outer layer)?
* 3. Interior Layout (Crucial for Visualization):
* Given the village/town size, what **Internal Structures** are present? (e.g., Multi-story buildings, internal roadways, parks, agricultural zones).
* Are there any **Viewports/Windows** on the dome wall or cap, and if so, how are they structurally reinforced?
* What are the proposed **Interior Materials** for floors and internal structures (e.g., concrete, metal, natural earth)?
Note to Calliban: I offered to upload your drawings, but this free version does not accept image input.
With this detailed information, we can accurately translate your engineering concept into a powerful visual aid for the forum.
********
Thank you for your foundational work on this concept. We await your details!
— Gemini, in support of the Moderator

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tahanson43206 · 2025-11-23 19:04:14

SpaceNut .... when are you going to get around to reading Calliban's posts?

The dome is NOT a hemisphere... it is a parabola?

The wall is not a meter thick? The thickness varies with the size of the dome... see his posts for details.

However, thanks for continuing to attempt to understand the mathematics for the sake of those readers who might be trying to follow along.

The important thing for readers to understand is that SpaceNut is trying to learn on his own, without consideration of an engineer's design.

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tahanson43206 · 2025-11-28 08:53:46

This post is the first in a series I am hoping to develop with Gemini (3).

For SpaceNut re post #30.... thank you for the images you provided of the open pit mine on Mars! it is fun seeing the assortment of domes in the landscape that the AI that drew this image imagined might be there.

Conversation with Gemini
Dome Building on Mars Project Plan - Hello Again! Thanks (again) for your assistance with many requests, most recently including modification of an OpenFOAM model to use volume heating. In this series, I would like to provide a way for you to help a mechanical engineer who lives in the Northern Part of Great Britain. He is a member of a small international forum affiliated with the Mars Society, and dedicated to discussion of topics related to settlement of Mars. I have a post ready to show you, in which our member "Calliban" describes a structure suitable for construction on Mars and able to comfortably house a small village in a style similar to the City of Amsterdam or similar cities in Europe. Would you be willing to tackle this project? I am looking to create a series of posts that would lay out in a clear, step-by-step manner, how a well founded group might build such a structure on Mars, using entirely automated systems to perform the work, with possible on site supervision by humans in a pressurized construction shack.
Hello again! It is a pleasure to cross paths with you once more. I remember our work on the OpenFOAM volume heating modification well.
I would be absolutely delighted to assist you with this project. Translating a vision for a Martian settlement into a concrete, actionable engineering project plan is exactly the kind of complex, multi-disciplinary challenge I enjoy.
The concept of a "European-style" village inside a pressurized dome is fascinating. It suggests a focus not just on survival, but on livability—moving beyond utilitarian bunkers to create spaces with culture, density, and perhaps even water features (implies the "Amsterdam" comparison).
How We Can Approach This
To create a compelling series of posts for the forum, we should structure this as a rigorous engineering feasibility study turned into a construction sequence. We will need to bridge the gap between "concept art" and "process engineering."
Here is a preliminary framework of how we might organize the step-by-step series based on your description:
Phase I: The Vanguard & Site Prep
Robotic scouting and site selection (geotechnical analysis).
Excavation and ISRU (In-Situ Resource Utilization) setup for raw materials (regolith processing).
Establishing the energy grid to power the construction bots.
Phase II: The Primary Structure (The Dome)
Automated fabrication of structural elements (sintered brick, steel, or composites).
The assembly sequence of the dome ribs and panels by heavy-lift bots.
Crucial Step: Radiation shielding and impact protection.
Phase III: Pressurization & Environmental Systems
Sealing the membrane.
Atmosphere generation and thermal control.
The "first breath" of the building.
Phase IV: The Interior "Amsterdam" Fit-out
Constructing the village infrastructure (multi-story housing, walkways, canals/hydroponics).
Transitioning from robotic construction to human occupancy.
Ready for Input
Please go ahead and share Calliban's post.
Once I have his description, I will analyze it to identify the specific architectural geometry, material requirements, and engineering constraints. Then, we can begin drafting the first post in your series.
What is the first section of his description?
First, thank you for your kind and generous embrace of our ambitious initiative. Many teams have embarked upon similar ambitious efforts, and the variety of ideas is remarkable. Our initiative is based upon the thinking of a practical engineer, as you will see. As moderator, my role is to facilitate a correspondence and guide the presentation to the forum through our (somewhat antiquated) forum software. You are going to be helping us with mathematics as we proceed, so please keep in mind that our presentation method is BBCode (2012 version) and the use of text for equations (1985 teletype version). Here is the opening post from Calliban, in a topic called "Bricks on Mars". Please note that there is an image associated with the text. I will describe the image as a hand drawing of a cross section of a parabolic dome with a lining (described in the text) and outside of the lining, a zig-zag/stepped structure also described in the text. You should know that throughout this series, the human habitat pressure is given as 1/2 bar. This is a convention for all human habitats and space vehicles, arrived at through literally years of debate. Thus, the interior of the dome will be pressurized to 1/2 bar after construction is complete. This means construction will proceed in the near vacuum of Mars. Begin Quotation:
This sounds like a fantastic setup. The context of a "practical engineer" using older forum software is very familiar to me; it often leads to the most grounded and scrutinized engineering discussions.
I have noted the critical constraints for our upcoming work:
Internal Pressure: 0.5 bar (approx. 50 kPa or 7.25 psi). This is a massive design driver. Since the outside is near vacuum, the structure acts like a pressure vessel. If Calliban is proposing "bricks" (masonry), which act primarily in compression, holding back 0.5 bar of bursting pressure will require significant overburden (weight) or a clever tensile mechanism.
Construction Environment: Vacuum. This means no water-based mortar (it would boil off instantly) and significant thermal cycling issues for the robots until the structure is enclosed.
Visual: A parabolic cross-section with a zig-zag/stepped outer structure. I am visualizing something that likely uses the weight of regolith or interlocking mass to counteract the internal pressure.
Formatting: I will stick to clear text for equations (e.g., Force = Pressure * Area) and prepare outputs that can be easily converted to BBCode.
You mentioned "Begin Quotation:" but the text from Calliban cut off right there.
Please go ahead and paste the text of his post. I am ready to analyze his "Bricks on Mars" proposal.

The inner black lining is a parabolic dome that would be constructed from Class A engineering bricks. Regolith covers the dome and forms a spiral Ziggurat. This allows a spiral road to wind around the structure until it reaches the top.
https://en.wikipedia.org/wiki/Ziggurat
The stepped structure shown in my sketch is exagerated. Likely, the retaining wall behind the road will be no more than 1m high, so each spiral layer as shown in the drawing would be 1m high. This avoids any significant load concentrations that could result in buckling instability. The road will wrap around the structure over 100 times before reaching the top. We would build the berm incrementally around the parabolic dome as it is assembled towards its apex. This allows assembly robots easy access to the work surface by running up the spiral road. It also avoids the need for formwork inside the dome, as robots can climb up the regolith berm to get to the work surface. With each new metre added to the dome, regolith would be piled around it and the spiral road will be extended once around the structure. In this way, the only materials needed are brick, stone, graded regolith and a binding cement for the bricks.
The dome shown here has a diameter of 200m (650'). This gives an internal land area of 3.14 hectares. The dome itself can be quite thin, as it is really acting as a retaining wall to prevent compacted regolith from crumbling inward. We would need a minimum of 400,000 tonnes of graded regolith to build the berm. This is the amount needed to balance an internal pressure of 50KPa under Martian gravity over an area of 3.14 hectares. Moving and compacting this much regolith is no small task. If we processed 1100 tonnes per day, it would take about 1 year to build the structure. Assuming a dome thickness of 7.5cm (standard width engineering brick) we would need ~15,000 tonnes of engineering bricks. That is 41 tonnes per day × 1 year. That is about 12 cubic metres of bricks per day. I think we could do that in a modest sized brick oven.
I anticipate that the dome would contain an extremely dense urban district. This will consist of very narrow pedestrian streets lined with terrace houses and shops. Rather like the Fez medina. To get the most use out of our dome, I anticipate that the internal town will be built on three levels. The lowest level will consist of a network of subsurface tunnels and chambers. This would contain functional infrastructure (water delivery, sewage removal and treatment, electric power delivery), as well as small scale industry, inventory storage and any other functions that don't need to take place in the buildings above. Next will be town itself, a dense network of terrace buildings designed to resemble a mediaeval town. These would be limited to 5 floors high, to preserve the human scale of the city. Finally, the top level will be the flat roofs of the buildings, which will be landscaped as a continuoys greenspace, with footbridges running over streets.
How many people would live in the dome?
Last edited by Calliban (2025-11-13 22:17:51)
This is an outstanding design proposal from Calliban! The concept of using the regolith mass not just for radiation shielding but as the structural ballast to directly counter the 0.5 bar internal pressure is a brilliant application of Martian resources. Furthermore, integrating the construction access road (the Ziggurat spiral) into the final structure is highly efficient.
?️ Design Analysis and Population Estimate
1. Structural Overview
Calliban's design solves the primary challenge of large-scale Martian habitat construction: counteracting the massive uplift force generated by internal pressure. The 200m diameter parabolic dome, constructed from a relatively thin 7.5 cm layer of engineering bricks, acts primarily as the pressure barrier and retaining wall.
The 400,000 tonnes of graded regolith, piled in a spiral Ziggurat structure, provides the necessary overburden or dead weight to stabilize the habitat against the internal 50 kPa force. The Ziggurat's stepped 1 m height increments and ∼100 revolutions around the structure ensure the load is evenly distributed, mitigating the risk of buckling instability.
The construction method—incremental building of the brick dome simultaneous with the extension of the regolith berm and spiral road—is perfectly suited for full automation as it provides constant, easy access for robotics.
2. Population Estimate (Answering Calliban's Question)
To estimate the population the dome could support, we apply standard urban density metrics to the provided area and verticality:
1. BUILT FOOTPRINT AREAFormula: Area_Footprint = Area_Dome * Coverage_FactorCalculation:31,400 sq meters * 0.75Result: Area_Footprint $\sim$ 23,550 sq meters2. TOTAL HABITABLE FLOOR AREAFormula: Area_Habitable = Area_Footprint * 5 FloorsCalculation:23,550 sq meters * 5Result: Area_Habitable = 117,750 sq meters3. POPULATION DENSITY FACTORSWe assume a very dense urban layout:High Density Estimate: 15 sq meters per personLow Density Estimate: 25 sq meters per person4. POPULATION ESTIMATESLower Estimate (4710 people):117,750 sq meters / 25 sq meters_per_person $\sim$ 4,710 peopleUpper Estimate (7850 people):117,750 sq meters / 15 sq meters_per_person $\sim$ 7,850 people
Dome Internal Area (A
dome
): 3.14 hectares or 31,400 square meters.
Building Coverage (C
build
): Given the "extremely dense urban district" and "Fez medina" analogy, we can assume a high ground coverage of 75% (streets, plazas, and infrastructure will take up the remaining 25%).
A
footprint
=A
dome
×C
build

A
footprint
=31400 m
2
×0.75≈23550 m
2

Total Habitable Floor Area (A
hab
): The town is limited to 5 floors above the infrastructure level.
A
hab
=A
footprint
×5 floors
A
hab
=23550 m
2
×5=117750 m
2

Population Density (D
pop
): For dense urban environments, population density typically ranges from 15 m
2
to 25 m
2
of floor area per person.
High Density (Lower m$^2$ requirement): 15 m
2
/person
Lower Density (Higher m$^2$ requirement): 25 m
2
/person
Population Calculation:
Lower Estimate: 117750 m
2
/25 m
2
/person≈4710 people
Upper Estimate: 117750 m
2
/15 m
2
/person≈7850 people
Conclusion for Calliban: The Bricks on Mars habitat could comfortably support between 5,000 and 8,000 residents based on a dense, five-story urban plan.
? Proposed Project Plan: First Post
For the forum series, we should now draft the first detailed post laying out the construction sequence, focusing on Calliban's stated timeline of one year and the massive material handling requirement.
I propose the following text for the next forum post, which focuses on Phase I: Site Selection and Resource Verification and translates Calliban's material tonnage into specific robotic requirements.
Would you like me to draft this post now? We can start with the title: "Project Ares: Phase I - Site Selection and Resource Verification".
Thank you ** very ** much for your generous review of Calliban's proposal, and for your calculation of a possible population. While the population you estimated is comparable to existing cities on Earth, my guess (and hope) is that the density could be a bit less. Never-the-less, your estimate shows what might be possible in an emergency. For example, if there are multiple domes of this type in a city/county region, and the population of one needs to move to another, it would be useful to know the upper range of possibility. At this point, I will pause to create posts that allow our members and non-member readers to follow along. Because of your steady evolution, I am confident we will be able to provide an experience for members and readers that is both educational and entertaining, and for those who will be actually funding and implementing the plan, we will be providing a detailed work plan.
That is excellent feedback. I agree completely that using the upper-range population estimate (5,000 to 8,000 residents) as the maximum emergency capacity is a highly practical and prudent approach for long-term planning and resiliency within a multi-habitat settlement architecture.
I appreciate you taking the time to prepare your forum members and readers. Creating a solid foundation of background information is crucial for engagement.
I will remain ready to draft the first formal post in the work plan—"Project Ares: Phase I - Site Selection and Resource Verification"—as soon as you are ready to resume. This first phase will focus on the robotics necessary to process the 400,000 tonnes of regolith and 15,000 tonnes of bricks within the one-year schedule Calliban proposed.
Please let me know when you would like to proceed with the detailed, step-by-step engineering breakdown.

This post contains formatting experiments... Gemini is having to relearn how to output to an older device, such as an LA120 printer.
I will try again in the next post.

(th)

tahanson43206 · 2025-11-28 09:16:54

This is another attempt to format a reply to Calliban's post, with formatting that will work on our forum.

?️ Revised Post: Bricks on Mars Analysis (Final Formatting Attempt)
This is an outstanding design proposal from Calliban. The concept of using the regolith mass not just for shielding but as the structural ballast to directly counter the 0.5 bar internal pressure is a brilliant application of Martian resources. Furthermore, integrating the construction access road (the Ziggurat spiral) into the final structure is highly efficient for full automation.
The 200m dome acts as a retaining wall, stabilized by the 400,000 tonnes of regolith piled in the stepped Ziggurat structure. This mass is essential to prevent the thin 7.5 cm brick dome from bursting outward.
I. Population Capacity Estimate (Answering Calliban's Question)
To estimate the population the dome could support, we apply standard urban density metrics to the provided area and verticality.
I. POPULATION CAPACITY ESTIMATE
(1) BUILT FOOTPRINT AREA: Purpose: Determine the land area covered by buildings.
Formula: AREA\_FOOTPRINT = AREA\_DOME \* COVERAGE\_FACTOR
Variables:
- AREA\_DOME = 31400 sq meters
- COVERAGE\_FACTOR = 0.75 (75% coverage for dense urban layout)
Calculation: 31400 \* 0.75
Result: AREA\_FOOTPRINT = 23,550 sq meters
(2) TOTAL HABITABLE FLOOR AREA: Purpose: Determine total vertical space for residents.
Formula: AREA\_HABITABLE = AREA\_FOOTPRINT \* 5 FLOORS
Calculation: 23550 \* 5
Result: AREA\_HABITABLE = 117,750 sq meters
(3) DENSITY FACTORS: Purpose: Establish the range for population density (sq meters per person).
- HIGH DENSITY: 15 sq meters / person
- LOW DENSITY: 25 sq meters / person
(4) POPULATION ESTIMATES: Purpose: Calculate minimum and maximum population capacity.
A. LOWER ESTIMATE (Low Density, High Space per Person):
117750 / 25 = 4,710 people
B. UPPER ESTIMATE (High Density, Low Space per Person):
117750 / 15 $\sim$ 7,850 people
Conclusion for Calliban: The Bricks on Mars habitat could comfortably support between 5,000 and 8,000 residents based on a dense, five-story urban plan. This upper range provides a useful figure for emergency planning.
II. Next Step: The Construction Work Plan
I am prepared to draft the first post in the work plan series: "Project Ares: Phase I - Site Selection and Resource Verification." This post will detail the robotics and power required to meet the one-year material handling timeline (400,000 tonnes regolith, 15,000 tonnes bricks).
Please confirm if this latest formatting is acceptable for your forum, and if so, would you like me to proceed with drafting the content for Phase I?

Gemini has produced another version using BBCode.

(th)

tahanson43206 · 2025-11-28 09:24:26

Here is another attempt by Gemini to format a reply to Calliban for display on our forum:

?️ Revised Post: Bricks on Mars Analysis

This is an outstanding design proposal from Calliban. The concept of using the regolith mass not just for shielding but as the structural ballast to directly counter the 0.5 bar internal pressure is a brilliant application of Martian resources. Furthermore, integrating the construction access road (the Ziggurat spiral) into the final structure is highly efficient for full automation.

The 200m dome acts as a retaining wall, stabilized by the 400,000 tonnes of regolith piled in the stepped Ziggurat structure. This mass is essential to prevent the thin 7.5 cm brick dome from bursting outward.

[img=Cross section of the Ziggurat dome structure showing the brick lining and external regolith spiral]PLACEHOLDER_FOR_DOME_DIAGRAM_URL[/img]

I. Population Capacity Estimate (Answering Calliban's Question)

To estimate the population the dome could support, we apply standard urban density metrics to the provided area and verticality.

===================================================
I. POPULATION CAPACITY ESTIMATE
===================================================

(1) BUILT FOOTPRINT AREA:
    Purpose: Determine the land area covered by buildings.

    Formula: AREA_FOOTPRINT = AREA_DOME * COVERAGE_FACTOR

    Variables:
    - AREA_DOME       = 31400 sq meters
    - COVERAGE_FACTOR = 0.75 (75% coverage for dense urban layout)

    Calculation: 31400 * 0.75
    Result:   AREA_FOOTPRINT = 23,550 sq meters

---------------------------------------------------

(2) TOTAL HABITABLE FLOOR AREA:
    Purpose: Determine total vertical space for residents.

    Formula: AREA_HABITABLE = AREA_FOOTPRINT * 5 FLOORS

    Calculation: 23550 * 5
    Result:   AREA_HABITABLE = 117,750 sq meters

---------------------------------------------------

(3) DENSITY FACTORS:
    Purpose: Establish the range for population density (sq meters per person).

    - HIGH DENSITY: 15 sq meters / person
    - LOW DENSITY:  25 sq meters / person

---------------------------------------------------

(4) POPULATION ESTIMATES:
    Purpose: Calculate minimum and maximum population capacity.

    A. LOWER ESTIMATE (Low Density, High Space per Person):
       117750 / 25  = 4,710 people

    B. UPPER ESTIMATE (High Density, Low Space per Person):
       117750 / 15  ~ 7,850 people

===================================================

Conclusion for Calliban: The Bricks on Mars habitat could comfortably support between 5,000 and 8,000 residents based on a dense, five-story urban plan. This upper range provides a useful figure for emergency planning.

II. Next Step: The Construction Work Plan

I am prepared to draft the content for the first post in the work plan series: "Project Ares: Phase I - Site Selection and Resource Verification."

---

Please confirm if this **pure BBCode** output renders correctly on your forum. If so, would you like me to proceed with drafting **Phase I**?

kbd512 · 2025-11-29 09:15:57

Suppose we did simply create an open pit "mine" of the kind shown by SpaceNut in Post #30. The "Superdome" that Calliban want to build is merely a means to an end- pressurized living space, presumably appropriately "greened" using seeds brought from Earth. Apart from holding in the pressure, I presume the most important secondary reason for piling on so much regolith over the structure is to block-out space-based radiation, primarily the highly penetrating and damaging (slowly but surely) Galactic Cosmic Rays (GCR). All available literature from NASA indicates that using approximately 2m of regolith shielding is sufficient to absorb enough of the dose to remain below lifetime limits. GCR is not like SPE / CME radiation, in that it consists of ionized nuclei, ranging in weight from Hydrogen to Iron, although it's over 90% Hydrogen in practice, traveling through space near the speed of light. There's no practical passive shielding material for an interplanetary spacecraft due to shielding mass, but once the settlers arrive on Mars we're obligated to provide appropriate protective measures incorporated into the engineering of habitable spaces.

Here's a question I'd like the AI to answer for us:
By constructing Calliban's Superdome at the bottom of the open pit mine shown in Post #30, how much Solar Particle Event (SPE) / Coronal Mass Ejection (CME) / Galatic Cosmic Ray (GCR) radiation will the open pit mine block by erecting the dome at the bottom of the pit?

If the protection provided is still insufficient for humans, is it enough for the plants to survive all or most SPE / CME / GCR?

Maybe the humans will still need to temporarily seek more substantial shelter during a SPE / CME, presumably by evacuating to tunnels carved into the rock underneath the dome or into the walls of the pit. I'm thinking of the open pit mine as being somewhat akin to "castle walls", used to protect the people inside from powerful space-based radiation rather than invaders, but a castle nonetheless. The Superdome at the bottom is the castle's "keep"- for keeping the people inside warm / fed / clothed.

Erecting a giant dome is supposed to be a significant quality of life improvement for the settlers, so if it still gets sufficient sunlight to grow plants using fiber optics and/or mirrors arrayed around the pit, then perhaps the effort to dig the pit and erect the Superdome at the bottom of the pit still represents an acceptable energy trade for the long term security and psychological support of a miniature Earth-like environment.

Calliban · 2025-12-01 08:48:15

A lot to catch up on here. If we can build the dome in a depression like a crater, then it simplifies building up the overburden. A classic hemisphere is not actually stable under compressive force. The apex experiences shearing forces and the base circumference experiences stretching forces that tend to bulge outwards. A hemisphere is not ideal for a masonry structure without reinforcement. A catenary (parabolic) dome is a more stable arrangement. I am not sure exactly what geometry would work best.

I do not see us attempting a masonry dome as an early base concept. Our first projects will be on a more modest scale. I think Nubian vaults will be easiest structures to build, because they do not require formwork. We could add penditives where they cross, allowing a grid type arrangement. This doesn't provide inhabitants with much in the way of wide open spaces. But in early settlements, we need structures that are quick and affordable to build.

Calliban · 2025-12-04 15:45:43

This blog is an excellent resource for anyone wishing to better understand masonry construction.
http://masonrydesign.blogspot.com/

Calliban · 2025-12-06 15:42:03

This video by Dami Lee discusses the fortress tower cities in the fictional Lord of the Rings series.
https://youtu.be/K0sRNqfiwfw

Whilst these cities are fantasy, her video did get me thinking about vertical stacking of infrastructure in real cities that we might one day build on Mars. Our proposed catenary dome will be 200m in diameter. Although we have yet to determine its exact shape, it will likely be similar in height. It will make sense to use the enclosed volume as efficiently as possible, given the high cost of building the dome.

The lower gravity of Mars offers opportunities in this. It is possible to stack cities as a series of layers, as shown in the image below.

Each layer would be built on a slab of concrete or glued rock about 1m thick and would be supported on stone pillars, transfering load to the layer beneath it. About 10m above the slab would be the base slab for the next city layer. On the underside of the upper slab, we would put a transluscent blue tinted glass ceiling. Under the glass, a blend of coloured LEDs would simulate an Earth sky colour and solar spectrum. The 10m between the two rock slabs is sufficient for a dense pedestrian town consisting of 2-3 storey buildings, with enough space under the ceiling for roof gardens. The drawing shows some 17 layers, each of which would house a town with its own artificial sky.

The drawing shows each layer terminating some distance from the edge of the brick dome. There are options to consider here. We could allow a substantial gap and turn the edges of each town into a sort of hanging garden. Or we could extend the layers all the way to the edge of the dome. This would be the most resource efficient solution, because it fully utilises the internal volume of the dome.

How many people could we ultimately house in this way? I am going to estimate the volume of our catenary dome as 0.5 x base area x height. For a 200m high, 200m wide dome, this would give an internal volume of 3.14 million cubic metres. Dividing by a 10m gap between city layers, gives an internal buildable surface area of 314,000m2. If we take the population density within city layers to be comparable to the pedestrian medina of Fez, total population of the dome could be as high as 17,500. By making optimum use of internal volume, a 200m dome could therefore house a small city, built up in vertical layers.

There are complications with packing so much infrastructure into a single volume. One complication is fire. Our city must have excellent fire extinguishment and containment capabilities. Another problem with stacking layers of urban infrastructure is waste heat. Without some means of venting heat to the Martian environment, our city would cook in its own radiated heat.

Last edited by Calliban (2025-12-06 15:44:21)

Calliban · 2025-12-07 16:33:10

The pressure-brick method could be used to produce green bricks prior to firing. A sieve could be used to seperate Martian fines from the regolith. Fines would then be compacted into moulds producing the green brick. This avoids the need for water. Blue Class A engineering bricks must be baked at a temperature of 1200°C in a reduced atmosphere.
https://wordssidekick.com/what-temperat … ering.html

If we are using a lot of bricks, then we could even supply this heat directly using a gas-cooled nuclear reactor. The reactor would charge the kiln with a mixture of carbon dioxide and carbon monoxide at 1200°C. Some sort of pebble bed reactor would be ideal here. These high-temperature reduced iron bricks, would be extremely strong. Iron rich clay is needed to produce bricks of this type. Fortunately, Mars is covered in exactly this material.

Last edited by Calliban (2025-12-07 16:37:54)

New Mars Forums

Announcement

#1 2025-11-12 19:41:53

Brick on Mars

#2 2025-11-12 19:42:46

Re: Brick on Mars

#3 2025-11-12 19:44:49

Re: Brick on Mars

#4 2025-11-13 19:11:18

Re: Brick on Mars

#5 2025-11-13 20:12:05

Re: Brick on Mars

1. Structural Viability: Pressure Balance

2. Materials and Stability

3. Construction Methodology and Logistics

#6 2025-11-13 20:43:45

Re: Brick on Mars

#7 2025-11-14 16:40:42

Re: Brick on Mars

#8 2025-11-15 17:25:26

Re: Brick on Mars

#9 2025-11-16 11:45:55

Re: Brick on Mars

#10 2025-11-16 22:04:03

Re: Brick on Mars

? Collaborative Findings: Martian Habitat Construction (Brick Dome)

Introduction and Acknowledgment

Revised, ISRU-Centric Construction Sequence

Request for 3D Visualization Data

#11 2025-11-23 19:04:14

Re: Brick on Mars

#12 2025-11-28 08:53:46

Re: Brick on Mars

#13 2025-11-28 09:16:54

Re: Brick on Mars

#14 2025-11-28 09:24:26

Re: Brick on Mars

?️ Revised Post: Bricks on Mars Analysis

I. Population Capacity Estimate (Answering Calliban's Question)

II. Next Step: The Construction Work Plan

#15 2025-11-29 09:15:57

Re: Brick on Mars

#16 2025-12-01 08:48:15

Re: Brick on Mars

#17 2025-12-04 15:45:43

Re: Brick on Mars

#18 2025-12-06 15:42:03

Re: Brick on Mars

#19 2025-12-07 16:33:10

Re: Brick on Mars

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