Concrete may have found it's killer app in graphene, that amazing carbon material super conductive, strong and flexible with many futuristic potential. The one thing I like about concrete is that the material can be worked with in any shape you can think of and the properties are more than sufficient for any application that doesn't require exotic properties. But at the same time, it has been tried and tested through out it's history and it does work. If by new material you mean something like graphene which might revolutionize the way electronics are constructed for the future you can say "they did the same in the past" and as soon as a better material was discovered, they started building the new way. However concrete has the advantage of being cheaper than graphene, available in every country on earth and works all the way to the subatomic particle level. This leaves graphene as a great idea and a wonderful test bed but the applications and materials required for it to be used to full capacity are a long way off. And that my friend is the reason I said what I said in my initial reply to you. Concrete can be molded to form and shape but we need more to keep the earth and environment in mind and I think we are getting there but with a lot more time before we get there. So I am left with this conclusion. If we are to have advanced material to support our needs, where would you rather live? Which will serve us better with fewer drawbacks. What is more important to you? Profit for corporations that are invested in large factories to produce materials and who do not give a crap about the world and the environment or the citizens that live here on earth? This is our home, not some business, so we should think of the best and safest way to handle our most vital components, our homes, as we would our lives. These are questions that any thinking person would like the answers to. 1) Because it's not actually concrete that can't go into the ground. It's the building code that prevents this. You can actually build your house out of something like polystyrene or, if you're into this kind of thing, a carbon fiber house, if the municipality approves it. 2) If I may say so, this is a terribly worded title. Can you say why it's ridiculous? 3) If concrete can't exist under water, how can concrete have any relationship to concrete at all, much less concrete on Mars? And why does the concrete on Mars have a higher melting point? 4) The only reason concrete is "not a good insulation material" is because it's not a good insulation material in it's current form. You can improve that by: a) using smaller aggregate for a smaller thermal mass; b) incorporating additives; c) using additives to alter it's chemical properties; and d) by mixing in another material. As has been said elsewhere on this forum, there's a wide variety of options that improve its thermal performance, not just mixing in other stuff. If you do want to stick with concrete, you can cut down on heat gain or heat loss by insulating the walls and keeping them cool, making sure to seal up all the gaps. The point of using concrete as a building material is because it's fire-resistant and doesn't decay; not because it's a good thermal insulator. 5) You have not proved that cement is a bad thermal insulator. You've said that cement isn't as good as the cement in a brick kiln. How is that relevant to the thermal insulation properties of cement? 6) Why are you even arguing? There are lots of high-end buildings that use cement. Buildings that are on fire and in the path of natural disasters, not to mention entire civilizations, have survived because of cement's ability to form a hard, waterproof shell. That's not irrelevant to the topic of building a habitat on Mars. If you actually read and thought about what has been said, you might notice that it's the quality of the cement in question. 7) If you could get really fancy, you might use both, in different layers. Then there's waterproof cement and super cement. 8) You said that you can have something like a concrete building that has enough aggregate to support itself. What would be so wrong with that? Maybe it can actually support itself if it's properly designed. If it's not properly designed and/or there's something wrong with the concrete, there could be problems. 9) Why would the cement get hotter at lower temperatures? It's not so much a concern for Mars as for deserts. Concrete would provide better insulation to a Mars habitat than conventional buildings in a desert because it would be cooler, not because it would be colder. 10) Why would you want to make the interior of the building colder? The interior would have to be insulated to a much higher degree than a conventional building and the windows would have to have active cooling systems, possibly providing heat to the outside. With the windows properly designed, it could actually provide a cooling effect for the building, even though it would be using more energy. 12) Concrete is a mixture of rocks, mostly aggregate with clay, sand, etc., to bind them together. So as far as the cement, you have the limestone to provide calcium oxide, and silica, along with other components. The calcium oxide is a combination of calcium oxide and water, which is carbonic acid. Then water comes along and it reacts with the silica. Then it's hardened by the aluminates, it's a chemical reaction and it happens in a limited time period. Just some suggestions from someone who likes concrete as a building material. Concrete is the preferred building material because it can take extreme thermal conditions. Waterproofing is important for keeping water out when you have a space station on the martian surface. When you heat and cool your living space you will get a lot of moisture in your structure that has to be exhausted. You can use concrete or you can use a metal structure with an insulator installed around it. In either case the interior would have to be dry to protect you from corrosion or degradation of the structure. These types of buildings would have doors that open up so you can let out some of the moisture and air. As far as building material the best choice to go to would be something you can work with. This is not a place for exotic materials or for materials that are difficult to get to. Concrete is the right choice because you can shape and form it to fit your needs. You can take a standard concrete mix and pour it into a mold or mold it into forms for a structure. Concrete will take the shape of the mold and forms you put it in. We all have experience with building with concrete so we all know how to get it to do what we want it to do. It is easy to work with as long as you are working with low strengths of concrete. If you want to talk about using some exotic material that is available but is exotic. Steel and titanium are fine materials and have been used for many decades for all sorts of things. But concrete is a material that is everywhere in the earth and everyone has worked with it so you can create whatever shape you want to suit your needs. It is much easier to get the quality you want from a standard concrete mix than some other exotic material. If you have a choice of a standard concrete mix or a material that is exotic and hard to get and expensive then you would not go with the exotic material. You want to find the lowest cost and quality product you can for your purpose. And that my friend is the reason I said what I said in my initial reply to you. Concrete can be molded to form and shape but we need more to keep the earth and environment in mind and I think we are getting there but with a lot more time before we get there. "We" meaning the builders of the habitat, not the Earth's inhabitants. By the way, there's nothing keeping us from moving to a location on Mars to construct the habitat, or even having the habitat constructed on Earth and then transporting the building blocks to the launch site or to where they'll be put together on Mars. It's going to take a lot longer to get people to Mars and assemble the habitat than if we were to do it on Earth. If Mars' resources are more important than Earth's resources, then we will build the habitat in Mars and transport the building blocks from there. (You can do the same with any building material.) So I am left with this conclusion. If we are to have advanced material to support our needs, where would you rather live? Which will serve us better with fewer drawbacks. What is more important to you? Profit for corporations that are invested in large factories to produce materials and who do not give a crap about the world and the environment or the citizens that live here on earth? This is our home, not some business, so we should think of the best and safest way to handle our most vital components, our homes, as we would our lives. I have to say that those goals are contradictory. The only way that the citizens of the Earth will be better served by a corporation is to sell the corporation (if it has any morals or ethics), and it's shareholders. It's impossible for one side or the other to lose in this discussion, although both sides might not care for the outcomes of the discussion (because both sides have a goal that is diametrically opposed to the other side). The corporation's goal is that it can make a profit