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  • 1.  GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 10-14-2018 09:13 AM
    Edited by Tirza Austin 10-14-2018 09:12 AM
    Hybrid Lightweight Gridshells and Tensioned Membrane Nano Model has been built to demonstrate the viability of combined Tensegrity structures where tensioned membrane PVC, ETFE, PTFE, or other lightweight fabric sheets can be stretched over lightweight anticlastic wooden or other type of rigid or flexible gridshell meshes which when combined can achieve long span roof covers, taking advantage of the lightweight semirigid gridshells created by sets of doubly ruled straight lines crossing over each other. Attached is a video and a collage of pictures of different views of the gridshell-membrane nano scale home-made model.

    ------------------------------
    Pedro Munoz Ph.D., P.E., M.ASCE
    Principal
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------


  • 2.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 11-15-2018 07:05 AM
    Edited by Tirza Austin 11-15-2018 07:04 AM
    Dear Pedro, thanks for sharing! These structures look great. Have you already tested the environmental aspects like freshness for air currents to implement these structures as a housing solution in hot weather areas? Did you performed structural models to improve its design (i.e. SAP2000 models)?

    Regards,

    ------------------------------
    Andres Guzman Ing., M.ASCE
    PROFESSOR
    UNIVERSIDAD DEL NORTE
    Barranquilla
    573004284680
    ------------------------------



  • 3.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 11-15-2018 01:23 PM
    Edited by Pedro Munoz 11-17-2018 01:36 PM
    Dear Andres, I am very glad to share this nanoscale model which I built to demonstrate a conceptual design of building Hyperbolic Paraboloids (HYPAR) 3D surfaces from set of intersecting straight lines within parabolic and rectilinear boundaries. The model that you see was built within the square footprint of a 5 ft. x 5 ft. tent which is supported only at the four corners. The entire wooden gridshell is framed onto intersecting parabolic-like shaped arches similar to what Candela did for his Groined Vaulted reinforced concrete shells.
    Attached is a 3D PDF file that can be viewed in 3D, rotate, zoom, etc. that was used to serve as a basis to build the wooden gridshell.
    The square footprint of the tent was divided into 5 modular Hypar Surfaces to demonstrate the versatility of using straight lines to generate different types of Hypar curvilinear surfaces.
    The AutoCAD DWG file contains the geometry of the entire 3D model which you could use to import it into SAP 2000 or STAAD-Pro or any other General Purpose 3D structural software to model the 3D Gridshell to study its behavior under loads. It will be very interesting to see what your findings are on the overall behavior of this Hybrid 3D gridshell, membrane structure particularly its strength, stiffness, and stability under snow and wind loading conditions, perhaps under seismic loads as well.. 
    Yesterday we had a 50 mph strong winds in the Greater Boston New England area, the nanoscale gridshell tent model took a huge shaking from the wind pressure, but it stood up without damage. So far, it has taken rain and wind. Today we expect the first round of SNOW here in Massachusetts for which I am looking forward to see how this model will handle the snow loads. I will share pictures later on when the snow storm is over.
    Please use the DWG file to see if you could study this 3D model under loads. Again this initial model is a proof of concept ONLY and has not been fully studied to be implemented for commercial or residential applications, but could certainly serve as a basis for further R&D. Take a look of Candela Shells and other similar Gridshell structures which had been build for Stations, Churches, Market Plazas, etc. to correlate the environmental and sustainable aspects of this gridshell applications. The roof covers cold be PVC, PTFE, ETFE, Bendable Plywood, or any other suitable curved metal decking, or light weight roofing material that can adapt well to the curvilinear surface of the gridshell. Bamboo for the boundary supporting structural parabolic or straight members comes to mind as well, .... Give it a try!!!, Please share your findings when they become available. It would be interesting to find out what type of adaptive applications might be suitable for the housing and commercial applications in hot weather areas like Barranquilla, Cartagena, Santa Marta, La Guajira, and so many other local regions of Colombia and South America, just to mention few.. Kind Regards.

    ------------------------------
    Pedro Munoz Ph.D., P.E., M.ASCE
    Principal
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------

    Attachment(s)

    pdf
    TENT48X4834-7.pdf   840 KB 1 version
    dwg
    TENT48X4834-7.dwg   761 KB 1 version


  • 4.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 12-10-2018 09:43 PM
    Edited by Tirza Austin 12-10-2018 09:43 PM
    Dear Pedro, thanks again for sharing those great files! (I am curious how do you prepare that 3D PDF file...). I will perform some structural analysis including earthquake and wind performance and let you know my results. I was thinking to check the overall performance for scenarios like community centres (to gather people around music, theatre, performance arts, etc.) in less favoured coastal areas.

    Have you ever heard about BLOCK research group in ETH Zurich and their amazing work?: BLOCK Research Group

    Regards,

    ------------------------------
    Andres Guzman Ing., M.ASCE
    PROFESSOR
    UNIVERSIDAD DEL NORTE
    Barranquilla
    573004284680
    ------------------------------



  • 5.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 12-11-2018 10:47 AM
    Edited by Tirza Austin 12-11-2018 10:47 AM
    Dear Andres, I am glad that you have looked at the files and find them of good interest to you.

    The 3D PDF file was created by importing the 3D Solid Model done in AutoCAD (DWG file) into Simlab Composer software (http://www.simlab-soft.com/) which is a very useful software for 3D Modeling and Rendering and then from Simlab Composer Export to 3D PDF, it is done in seconds. There may be other software out there that will do something similar, but this program I had been using for years and becomes very useful to share my 3D Conceptual Models and Designs  with anyone that can open PDF files. The 3D Model has to be done with solid members to be able to bring them into Simlab Composer.

    The 3D conceptual model that you see in the DWG and 3D PDF files were recreated in the form of a wooden gridshell frame covered with a stretchable cloth that was clamped around the boundaries of the 5 modular sections of the model to simulate a tensioned fabric structure which I call "TENSHELLGRIDITY CANOPY", I left it in my backyard this Fall Season waiting for the snow to come and just this past month of November we had two snow storms of about 6" to 8" each which certainly did the work to overload the conceptual model to an extreme deflected condition, The attached files show the 3D conceptual model after completion, before the snow storm, after the snow storms overloaded and deflected considerably, and a video of how it looks now that I had resupported the original model after the deflected conditions. I have introduced some few interior supports and added a center post in the middle of the canopy to see how it will behave after the upcoming snow storms of the Winter 2018-2019 Season start bringing lots of snow here in the New England-Boston area, USA..

    It will certainly be very interesting to see how your structural analysis will show results for different loading conditions. You may have to assign proper member sizes, support conditions, etc. This will be part of the interesting modeling study that will certainly bring some interesting discussions on how to address boundary conditions and member sizes to unusual 3D gridshell and membrane structures combined. The conceptual model that I present in the 3D PDF and DWG files were mainly to demonstrate the parametric generation of Graphical Form Finding of Hyperbolic Paraboloid Anticlastic Surfaces that were built by Master Architect Engineer Felix Candela in Mexico some more than 50 years ago and which I would think can be revived today in the form of GridShell Lightweight Structures that could combine all sorts of framework for the gridshell and also for the membrane,

    Thinking of Countries like Colombia Bamboo comes to mind and also local fabric and membranes which people in the country side can build on their own. "Applied Adaptive Technologies for Developing Countries" using local resources and local materials that can also be build with light weight tools and creative minds. Think about the talented people of "La Guajira" the very creative people of "San Jacinto" using their hands to come up withe very lightweight shade cover structures, there is so much that can be done with local material and lightweight tools. Please carry on with your research and see if you could create your own group of students that can spark their minds into adaptive solutions to their local regions, I am sure they will get into it once you show them some interesting projects to do on their own.

    Yes, I have followed the work of the BRG for some years ago when I started to do my: Literature Review for my Master Thesis on the subject of Shell Structures, in fact I had just graduated this past March 2018 with a Master of Engineering in Membrane Structures that I completed in Germany at the Institute of Membrane and Shell Structures - IMS Bauhaus - www.ims-institute.org - below a link to my Master Thesis for your review and perusal.

    http://ehub51.webhostinghub.com/~prmeng5/MASTERTHESIS-PRM-400dpi-02262018.pdf

    Keep up with your good research work and see if you could INSPIRE some of your students into doing something creative.

    Remember the 3 I's: INSPIRATION-INTUITION-INNOVATION ...............


    ------------------------------
    Pedro Munoz Ph.D., P.E., M.ASCE
    Principal
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------

     Video


  • 6.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 12-28-2018 10:47 AM
    Edited by Tirza Austin 12-28-2018 01:05 PM
    Dear all,

    I wonder how the Nano perbolyic project went on? As far as it updated in the recent posts. The models were still at the back yard. The Nano models tested due wind, rain and snow loads. It might be a good time to take your Nano models to Texas and let them experience tornadoes this time. You will be amazed of hitting by 250mph.

    ------------------------------
    Sayed Maqsood S.M.ASCE
    Currently Looking for Employment
    Oakland CA
    (510)395-4361
    ------------------------------



  • 7.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 12-28-2018 03:19 PM
    Edited by Tirza Austin 12-28-2018 03:18 PM
      |   view attached
    Dear Sayed, the Nano Scale Conceptual Model of the 5-Sections Hyperbolic Paraboloid (Hypar) Canopy built with a gridshell of straight-line wooden round sticks and covered with a stretchable cloth that has been clamped around the boundaries and along the valley lines of the modular sections is still standing up in my backyard waiting for the round of snow storms of the 2018-2019 Winter Season of North Eastern Massachusetts (MA) where it has also seen and stood up to winds of some 50 to 60 mph.
    Due to scale effects it would be interesting to know what correlation of wind pressure will correspond to a real scale canopy 6 to 8 times larger.
    As you could see the Nano Scale Model suffered tremendous deformations due to some 6" to 8" of snow this past November 2018. Interestingly enough the modular sections basically rotated inward, some few round wooden members broke, but it was not totally destroyed. When I went out to the backyard to see the effect of the snow loads on the model I was surprised to see that I could be able to rebuild it by adding some interior central support of the model and some additional vertical support and edge members around the perimeter boundary members along the four sides.
    In the latest video you could see the additional supports that I added around the perimeter and the center vertical support, the tensioned and clamped cloth basically remained intact except for some minor damage around the corner supports to the ground where the model experienced the majority of the axial forces from all the snow over the surface of the model. I also added some extra masonry blocks to help support the uplift wind loads.
    It is now standing up in the backyard and waiting for a real good snow storm, let's wait until February to see what happens and how the resupported Nano Scale Model behaves.
    Attached is a 3D DWG AutoCAD Model of the Canopy that can be used by any research group of students who would like to experiment with member sections properties, member sizes, support conditions and apply any type of code specified selfweigth, snow, wind, seismic, and all possible load combinations to see how the Nano Scale Model behaves and from that draw some interesting guidelines of member sizing and support conditions.
    Even some of that 250 mph wind pressure of Texas could be applied to study the overall behavior of internal forces, displacements, and stresses. The 3D DXF model from the DWG model can be imported into one of those General Purpose 3D Structural Analysis software to see what happens, This might be an interesting Summer Project for a group of Students in Texas or Florida. Give it a try !!!!!!! I am sure that members sizes and support conditions may need to be properly set to withstand the 250 mph wind pressure and uplift forces in TX or FL.
    Will keep you all posted once we get the next round of heavy snow here in MA. Happy New Year 2019.

    ------------------------------
    Pedro Munoz Ph.D., P.E., M.ASCE
    Principal
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------

    Attachment(s)

    dwg
    TENT48X4834-7.dwg   761 KB 1 version


  • 8.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 01-23-2019 11:32 AM
    Edited by Tirza Austin 01-23-2019 11:31 AM
    GRIDSHELL-MEMBRANE NANO-SCALE MODEL UNDER HEAVY SNOW LOADS

    Just this past weekend the New England Greater Boston area had snow storms between 12" to 20," the original nano scale gridshell-membrane model which had some partial collapse due to snow was modified by introducing some additional interior and boundary vertical supports. The modified model stood up quite well to the snow without significant damage, just minor movements of some of the improvised stick wooden supports. It is quite amazing how a HYPAR ANTICLASTIC gridshell composed of intersecting circular wooden members in the Candela style of building formwork performs quite well with the tensioned membrane which is clamped to the borders. The interaction of struts and membrane along the boundaries make this system quite effective without the need of any cables to support the tensioned membrane. From Solid Concrete Shells of Candela to the Lattice type Gridshell-Membrane proves to be lightweight and efficient to support both wind and snow loads.

    ------------------------------
    Pedro Munoz Ph.D., P.E., M.ASCE
    Principal
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------

     Video


  • 9.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 02-24-2019 10:19 PM
    Edited by Tirza Austin 02-24-2019 10:18 PM
      |   view attached
    Dear Pedro, thank you for sharing your excellent master thesis. Experimental research sometimes is so hard to present inside a text because the physical effort should be evidential in words.

    Enclosed, I also want to share a Master thesis from one of my students in Barranquilla (I noticed that you are also from Colombia, excelente!!! será un placer tenerte en Colombia para hablar sobre estos temas). This thesis covers a statistical approach to the structural analysis of concrete vaults.

    Regarding your last post, I noticed that that the <g class="gr_ gr_571 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling" id="571" data-gr-id="571">gridshell</g> membrane anticlastic model works great!! I will continue encouraging my students to prepare projects with light (but strong) elements like "guadua".

    Regards,

    ------------------------------
    Andres Guzman
    UNIVERSIDAD DEL NORTE
    Barranquilla
    573004284680
    ------------------------------

    Attachment(s)

    pdf
    d170215 Tesis JLAV Final.pdf   4.46 MB 1 version


  • 10.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    This message was posted by a user wishing to remain anonymous
    Posted 02-25-2019 02:26 PM
    Edited by Tirza Austin 02-25-2019 02:33 PM
    This post was removed


  • 11.  RE: GRIDSHELL-MEMBRANE Anticlastic Nano Model

    Posted 02-25-2019 02:32 PM
    Edited by Tirza Austin 02-25-2019 02:31 PM
    Dear Andres,

    I am very happy to see that you encourage your students to venture into experimental, theoretical, and computational research and Thesis work, that is a great approach for students to learn and explore new topics. I will take some time to go over and read your students' Thesis.
    Si soy de Cartagena y me vine a USA a estudiar Maestria y Doctorado a NJIT New Jersey Institute of Technoloty www.njit.edu  years ago. Estare muy complacido de conversar sobre temas de Ingenieria Estructural .... vamos a ver cuando nos lo permita Dios.

    Thank You for sharing this Master Thesis, see if you could ask your students to publish in the ASCE or ACI Journals or to encourage them to attend ACI and ASCE Conventions in the USA or Regional similar venues.

    I foresee tremendous great applications of BAMBOO gridshell membrane structures in developing countries ... given the fact that Bamboo is readily available and has tremendous mechanical properties and membranes can be done with local textiles which are also abundant in developing countries ... for shading, semi permanent, or permanent roof covers done with more durable and waterproof membranes, live PVC or PTFE, or similar ones ... ETFE can also be used for similar roof applications.

    Great you are thinking BAMBOO ... Anticlastic Gridshell Paraboiic Funicular Forms are very effective to cover long spans with lightweight materials ... Synclastic Forms like an EGGSHELL ratio of t/L of approximately 1/150 can be easily achieved with lightweight materials as well. Give it a try, you could have your students do a Workshop with small scale models .... and probably set up a Contest ... to encourage creativity ... etc. Try 3D Printing .... Hand-made models ... let the students design in 3D different forms using AutoCAD or Rhino ... and then build the models using wood, wires, etc. Kind of going from Digital to Physical Models ....

    Recently I have been building small scale models myself in my Studio and setting them out in the Backyard to expose them to SNOW, WIND, RAIN, and the elements.... seeing them react to wind and snow is a great learning experience. Give it a try.

    My Tent Wooden Gridshell-Membrane Model finally collapsed due to a recent heavy snow and freezing rain accompanied by strong winds. The diagonal arches had a global stability failure and the heavy snow brought it down, but learned a lot. We will dismantle it and see how the members failed.
    This model was built purely as a proof of concept to build different types of modular hypar forms. No calculations were done, purely experimentation with form first, now I see the strong and weak points. With the next one, we will be a bit more strong along the line of the diagonal groined arches.

    Stay tuned and stay in touch. Kind Regards!








    ------------------------------
    Pedro Munoz
    PRM Engineering, LLC
    Methuen MA
    (978)7388001
    ------------------------------