On a previous post, Why Bricks for a Mars Colony, I talked about a few reasons bricks make sense. On social media may people came back with the comment that it requires too much water to make bricks.
Not all brick-making requires water. The above video is an ad for a hydraulic brick press. It operates by adding enough tons pressure to turn loose materials in hard, solid bricks without water. There are hundreds of versions of the machine by hundreds of companies worldwide. Some very simple, and others far more complex and automated.
Test done on earth with the same ingredients the lenders have found on Mars show such Bricks to have a hardness roughly equal to steel-reinforced concrete. This is because of the high iron oxide content in most of the regolith. Such bricks would have a very high durability.
Nor is water necessary for mortar. The above is stacked bricks without mortar. The technique is called Dry Stone construction. There are buildings and walls thousands of years old built with this technique.
Conserving water will be important on a Mars Colony. Brick construction, unlike the three-D printing technology being considered, can be done without water.
Eptle 
I watched the video of the above machine making bricks. Looks a little too good to be true. The machine quickly pressed the loose material and a hard brick came out. Maybe the material was heated to a high temperature before being pressed, or some kind of binder was added to the mix. Note that the video does not show the details.
I read somewhere this may work if the dust which contains iron oxide and other metals is heated with microwaves before being pressed.
The building that is shown stacked without mortar will most likely collapse like a house of cards if hit on the side. The roof looks even weaker. A bigger structure may just make the stability even worse. The best building shape may be a dome made of interlocked bricks which have a wider base facing outwards and a narrower one facing inwards.
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If I remember correctly the building you mention is more than a thousand years old and still stands
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That building will likely stand another thousand years, if nobody bothers it. Yet, if you hit its rooftop sideways, it will come off. Regardless of how strong the bricks are.
An interlocked design would make use of the brick strength. You can’t destroy the building without destroying the bricks. Oh, and even an arch design would be stronger than the building shown here.
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