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Large-scale 3D printing of precast and cast-in-place concrete

  • 1.  Large-scale 3D printing of precast and cast-in-place concrete

    Posted 05-15-2018 12:42 PM

    I serve, as one of a group of advisers, for a confidential project with a short-term goal of 3D printing, as a demonstration, another concrete house in the U.S.  Based on what I have learned so far (two months), large-scale 3D printing could explode within civil engineering in the next few years, although maybe not in the U.S.

     Elon Musk and his crew of engineers land rockets in reverse and reuse them. In the same spirit of creativity/innovation, maybe the U.S. civil/construction engineering community can 3D print, in concrete and other materials, pre-cast components of buildings and other structures and entire buildings and other structures. By "other structures" I mean essentially everything we now do in formed concrete and beyond.

     Why try to do it?

     *  Reduce construction costs (less manual labor, less material, less wasted material, less energy use, etc.)

     *  Produce structures that are more resistant to natural disasters and terrorism (e.g., use new materials and stronger shapes/configurations)

     *  Slash prototyping time and fail faster

     *  Increase construction site safety

     *  Reduce construction time

     *  Customize each product

     *  Produce a whole new set of tech and other jobs (educators-trainers, structure designers, building code experts, programmers/coders, robot designers-manufacturers-transporters-operators-maintainers, finance experts, site acquisition specialists, government regulations/relations personnel, etc.).

     *Provide greatly improved affordable housing in the U.S. and around the globe.

     

    I am finding, as I suspect you have, that small 3D printers are showing up everywhere -- in K-12 schools and in universities, in public libraries, in homes, etc.  Use of larger 3D printers is taking off in manufacturing. In that sector, it is sometimes referred to as additive manufacturing, in contrast with traditional reductive manufacturing (e.g., milling, turning, boring, etc.).

     My hope is that some of you -- maybe "off the top of your head" -- can answer this question: Who, in mostly U.S. engineering academia or practice is studying/teaching/researching/developing large-scale 3D printing within the civil/construction engineering field?

    In addition, any thoughts you may have would be appreciated.

    Thank you.

     



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    Stuart G. Walesh Ph.D., P.E., D.WRE(Ret.), Dist.M.ASCE, F.NSPE
    S.G. Walesh Consulting
    219-242-1704
    stuwalesh@...
    www.HelpingYouEngineerYourFuture.com
    Author of Introduction to Creativity and Innovation for Engineers, 2017, Pearson
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  • 2.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 05-18-2018 01:31 PM
    Edited by Tirza Austin 05-18-2018 01:31 PM
    ​Immediate thought was foamed rigid plastic for concrete inside fills being formed!

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    www.gasturbineandersen.com Len Andersen Going to Norway June Engineer
    Water Swirled Gas Turbine Technology
    New York NY 10116-1529
    (914)536-7101
    Engineer - Gas Turbine Welding CWI
    + 20 yrs experience
    len@...
    914-536-7101
    800-428-4801Len
    ------------------------------



  • 3.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 06-29-2018 12:03 PM
    The US Military is experimenting with 3D printing structures. The Navy and Army are developing this as a viable option for construction option currently.  https://www.usni.org/magazines/proceedings/2016-10/3d-printing-game-changer 
    https://3dprint.com/185151/us-army-3d-printed-barracks/

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    Thomas Halmi P.E., M.ASCE
    Senior Facilities Engineer
    Steelcase
    Belmont MI
    (616) 866-8863
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  • 4.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 06-29-2018 02:20 PM
    Edited by Tirza Austin 06-29-2018 02:19 PM
    Here are some more links/resources to consider:

    http://contourcrafting.com/ 

    https://www.military.com/defensetech/2014/01/20/navy-helps-fund-3d-printing-of-buildings

    http://www.military.com/video/forces/army/3-d-printing-a-building-aces/5556042994001


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    Thomas Halmi P.E., M.ASCE
    Senior Facilities Engineer
    Steelcase
    Belmont MI
    (616) 866-8863
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  • 5.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 07-02-2018 11:05 AM
    Edited by Tirza Austin 07-02-2018 11:05 AM
    Thomas Halmi:

    Thank you for sharing information about military use of large scale 3D printing. You caused me to think further about the following:

    1) Our military values speed in construction both in combat and in providing post-natural disaster aid. 3D printing has the potential to do that.

    2) Large scale 3D printing, compared to conventional construction, will sometimes have the advantage of using locally-sourced materials. This assumes, of course, that the necessary printing equipment and expertise can be transported to the area.

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    Stuart Walesh Ph.D., P.E., D.WRE(Ret.), Dist.M.ASCE
    S. G. Walesh Consulting
    www.HelpingYouEngineerYourFuture.com
    stuwalesh@...
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  • 6.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 07-02-2018 09:56 AM
    Edited by Tirza Austin 07-02-2018 09:56 AM
    You may need to look at architecture schools if you want to be on the cutting edge of 3D printing.  There is a lively interest in building components produced by 3D printing.  Most of the interest is in aesthetic components, because of the ability of 3D printing to cheaply replicate complex geometries (think ornament).  Acoustic treatments also could probably be done inexpensively with 3D printing.

    Since 3D printers don't install reinforcement, I have wondered about 3D printers being used to create innovative formwork, with concrete placement done conventionally (that process is already well-optimized).

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    Elwin Robison M.ASCE
    Robison Building Analysis
    Kent OH

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  • 7.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 07-03-2018 09:49 AM
    Edited by Tirza Austin 07-03-2018 09:48 AM
    Stuart, 

    I've been puzzling over this topic of 3D printed concrete for a while and following the news.  In the information found on Google, I have not found anything on some really key points related to this technology.  

    1. How will a 3D printed structure respond to differential movements in the foundations?  I imagine this will be similar to a CMU block wall but I haven't seen anything meaningful about this. I know a lot of engineers who want to forget that there is no stress without strain. 
    2. Can horizontal structures (Beams, Floors, Roofs) be printed directly in the field?  The things I've seen like the dutch bridge (link below) have been vertical surfaces that have then been picked and placed.  For residential and commercial applications it seams likely that this type of structure is more efficiently produced in a precast plant.  I do think that horizontal concrete structures could be printed in the field if we model them on the methods developed for hand built mud brick domes.   
    3. I haven't seen much on incorporating water pipes, electrical conduits etc. directly into the 3D printed structures.  I've seen several projects where the finishing work tool more schedule then erecting the building.  3D printing has this capability and once it is properly developed the cost and time savings here will likely be the force that pushes 3D printed structures into the forefront. 

     
    Keep up the good work, 


    PS: The low hanging fruit here is likely in 3D printing form work like Bechtel did in London (link below). 

    https://www.youtube.com/watch?v=EnW3yeZ-CSc
    https://www.constructionequipment.com/bechtel-using-wax-and-3d-printing-build-london-tube​

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    Wendell Solomon P.E., M.ASCE
    SR PROJ CONSULT
    SME
    Westfield IN
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  • 8.  RE: Large-scale 3D printing of precast and cast-in-place concrete
    Best Answer

    Posted 07-03-2018 09:57 AM
    Edited by Stuart Walesh 07-05-2018 12:01 PM
    In terms of 3D printing buildings, I simply don't get it. If someone 3D printed a bolt, I would wonder "why didn't you simply go to the hardware store and buy a box of bolts?" We can mass produce bolts very efficiently.  Similarly, if you 3D printed a CMU block, I would wonder the same thing--the ability to mass produce CMU blocks already exists.

    With buildings, even in the 1990's a single production line could manufacturer 24 homes in an 8-hour shift, fully furnished, conforming to a building code--all you had to do is connect the utilities. Current headlines touting the 3D printing of a concrete home in 24-hours don't seem that remarkable--this is a very long time to complete ONLY the walls. And, it increases the required degree of skill and training in the field--the place where it is often most difficult to find skilled labor.

    Don't get me wrong, additive manufacturing has some great benefits or certain parts and products, but it is hard to imagine 3D printing a home in the field. We've had clients that have attempted to roll form steel in the field, on the job site, and failed due to finding skilled labor that will babysit the equipment.

    From an affordable housing standpoint, I work in affordable and disaster relief housing. Many have tried to bring new technologies to the industry, but the thing about new technologies, they are very expensive--typically not something that fits within the affordable housing market. Most new building technologies start at the high-end and attempt to work their way down before they go broke (e.g. Tesla).

    It seems to be a millennial "thing" to 3D print everything. In a recent college class, I taught, the students printed and built a device that at the end was a glorified cordless Dremel. It cost $500 to make when they could have gone to the local Lowe's (or Amazon) and bought a better version for $50. I'm sure the price of 3D printing will come down, but to compete with the cost of conventional materials will be difficult.

    I suggest that anyone truly interested in affordable housing or mass-produced housing review a building production facility and study the current state-of-the-art in order to know how far they must go.  And, the state-of-the-art is rapidly changing in-plant with large tech firms getting involved in ventures such as Katerra, Kasita, Z-Modular, BluePrint Robotics. The key difference between these startups and 3D printing--these companies are actually selling buildings today.

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    Eric
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  • 9.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 07-06-2018 04:20 PM
    Edited by Tirza Austin 07-06-2018 04:20 PM
    ​If 3D printing of houses is successful, it is likely that the entire concrete construction industry will be affected. Not only could design of wall systems and building floor-plans be transformed, conventional approaches to construction, testing, and inspection could need updating. It may also bring additional historically underutilized personnel into the concrete construction industry in a variety of roles. I agree, however, that many challenges exist for the successful implementation of 3D concrete printing, and many opportunities exist to learn and improve on the existing technologies.

    As far as industry relevance goes, the American Concrete Institute national convention in Anaheim, California featured two highly attended half-day technical sessions on the topic of additive manufacturing and concrete. It appears that the research engines are gearing up in the U.S. and around the world, so it should get interesting over the coming decade.

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    Kevin D. Copeland, PE. A.M.ASCE
    Austin TX

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  • 10.  RE: Large-scale 3D printing of precast and cast-in-place concrete

    Posted 07-07-2018 10:02 AM
    Edited by Tirza Austin 07-07-2018 10:02 AM
    The funniest thing in 3D printing is that the defining characteristic is not the printing technology itself, but rather the materials used. Most people are used to PLA or ABS going just fine as injected materials followed by phase transformation from solid to liquid, situation that does not apply to concrete. Of course, shotcrete technology which is, basically, the same except for the cartesian or delta placement, is used for years, but the end result is just a shell over an existing support and not necessarily a stand-alone structure built layer by layer.

    The reinforcement is, at its turn, a solvable problem since it may be employed disperse reinforcement or even classical reinforcement with low diameter bars installed during injection.

    In my opinion the actual problem is that the reinforced concrete structure thus created is definitely orthotropic with layers having a high air content and very poor quality control. Depending on the purpose this may be acceptable or not. The point is that the shortcoming of reinforced concrete leaves space for other materials which are better suited for the job. In my search for such materials I noticed that there are some promising polymers, but for the time being too expensive due to the low demand, mainly.

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    Manole Serbulea, Eng. MSc. PhD.
    Professor
    Technical University of Civil Engineering Bucharest
    Romania
    +40(0)726266537
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