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Something like this:

Of course I'm not pretending to achieve that level of detail, but is there any other way of obtaining similar results without having to spend so much time sculpting?

Basically, how do you model broken concrete? I tried with displacement modifier, but the results were too noisy and sharp, probably because I chose a bad texture but still I don't think I can achieve good results that way.

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    $\begingroup$ @cegatron ? that's the point of the question, I tried with displace modifier but it didn't work well. I'm not asking for the whole process or even to describe it, I only wanted to know the most adequate tools for the task within blender. Isn't that the point of the site? $\endgroup$ – Ant Oct 9 '15 at 8:24
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If you plan to texture this, read through all the steps once before beginning. There is a UV mapping tip at the end that requires planning in advance.

Now let's get on with it...

Start with a cube, make it tall

Start with a cube, scaled up along Z

Add a plane and fractal subdivide it

Fractal subdivide

Fractal subdivide it again

This time a little more "fractally".

(If by any chance this is going to be a game asset go with a lower number of subdivisions.)

Fractal subdivide again

Extrude your subdivided plane to give it thickness

Extrude your subdivided plane to give it thickness

Set up a boolean (Optional: Subdivide the column too)

For the boolean, set the Operation to "Difference" because you're carving out of your column.

Subdivide the column (non-fractal) if you want the two meshes to be of similar density. Having a denser mesh would be better if you plan to do something like mutires sculpting on this. Having a less dense mesh would be better if this will be used as a game asset.

Set up a boolean, and subdivide the column too

Apply the boolean, delete any leftover unneeded geometry

Apply the Boolean Modifier from Object Mode.

Then you can move your plane object to another layer or even delete it. After moving it you can see the subtractive boolean result.

To clean up stray geometry you don't need, select any part of those pieces in Edit Mode, press CtrlL to Select Linked geometry, then Delete (X) it.

Delete any leftover unneeded geometry

Note that this is just a start. You can further sculpt this of course.

Bonus Tip: UV Mapping

Since your reference image has textures I will mention a texturing tip. If you plan ahead you can UV map this whole thing neatly. Booleans respect and will combine UV data.

  • UV unwrap your plane before you subdivide it. From the top, "Project from view (Bounds)".

  • UV unwrap your column before subdividing and before applying the boolean. "Smart UV Project" with an Island Margin of 0.1.

  • To place the fractal-subdivided UV island: Select the five flat faces of the column (may need to Select Similar (ShiftG) > "Co-Planar" if you've subdivided the column too). Invert the selection (CtrlI). In the UV/Image Editor Box Select (B) the rest of the visible vertices and scale/grab to position as desired.

An example of the sort of UV layout you can create:

You can even UV map this if you plan ahead

Note: In the screen shot above the column was not subdivided before doing the boolean. It is a different .blend file from that of the preceding screen shots.

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  • $\begingroup$ Wow, that's much more than I was asking for, simply saying "fractal + boolean" would have been enough. Needless to say, thanks for the tips. $\endgroup$ – Ant Oct 9 '15 at 8:04
  • $\begingroup$ This is a little tutorial man :) Thanks so much for this simple and powerfull method $\endgroup$ – SottoZen Oct 9 '15 at 11:18
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    $\begingroup$ @Ant Glad you found it helpful. :-) At first I thought this question would be too niche to be useful to a broad audience because like, how many people on here will be searching "concrete pillar"? But on second thought I realized maybe the principles of the modeling process could be relevant to people looking to create all sorts of similar structures... so I went into detail. Happy blending! $\endgroup$ – Mentalist Oct 10 '15 at 3:05
  • $\begingroup$ You can use the Blender Port of Zbrush ORB Brushes, they are very very good for such cases. You can get them here. $\endgroup$ – Reuben X Aug 17 '18 at 22:22

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