www.contourcrafting.org
The test was designed to closely mimic a layered fabrication process, which subjects fresh cementitious extrudate to discrete increments of load. The test specimens are prepared per ASTM C 192, in extrudable cylindrical molds. After consolidation the specimens are carefully extruded from the mold with negligible disturbance, and simply placed upon a sturdy surface. At regular intervals, chosen to emulate candidate fabrication regimens, metal plates are placed upon the unconfined test specimens. These metal
Drucker-Prager plasticity describes the behavior of granular materials and polymers in which inelastic deformation is often associated with frictional mechanisms such as sliding of particles across each other. ). In ABAQUS Drucker-Prager plasticity is available with three different yield criteria. The differences in the criteria stem from the shape of the assumed yield surface in the meridional (p-q stress) plane.
"Hardening" provides for evolution of the D-P yield surface, and results at large strains are readily brought into excellent agreement with test, by implementation of a simple strain-related hardening rule.
With hardening implemented, the simulation predicts 0.75 inches of axial deflection at the extreme applied load of 12.5 lbf (the equivalent of 8 road weights) – the result is within 1% of the tested deflection.
A mortar-layering demonstration demonstrates that full-scale freeform layering of unconfined and self-supporting fresh mortar is feasible and safe when properly engineered. An 8-foot structure is erected with 30 layers of highly workable, yet shape-stable mortar. The remarkable thing is that the mortar is fresh and unconfined, meaning each free-standing 'brick' is gaining strength, as it cures, just fast enough to support on its own, the increasing weight of the other layers accumulating above it.
Numerical simulations of fresh mortar specimens loaded in axial compression at specific mortar maturities. The finite element analyses use the linear Drucker-Prager elasto-plastic model (Step-Time=0.12)
Numerical simulations of fresh mortar specimens loaded in axial compression at specific mortar maturities. The finite element analyses use the linear Drucker-Prager elasto-plastic model (Step-Time=0.24)
Numerical simulations of fresh mortar specimens loaded in axial compression at specific mortar maturities. The finite element analyses use the linear Drucker-Prager elasto-plastic model (Step-Time=0.48)
Numerical simulations of fresh mortar specimens loaded in axial compression at specific mortar maturities. The finite element analyses use the linear Drucker-Prager elasto-plastic model (Step-Time=0.60)
Numerical simulations of fresh mortar specimens loaded in axial compression at specific mortar maturities. The finite element analyses use the linear Drucker-Prager elasto-plastic model (Step-Time=0.72)

FEA for Formless-Concreting*

7th - Fans votes of POTY 2013 Edition

Created on 2016.05.17 316 views
6
ABOUT
PROJECT TIMELINE

*An 8 foot structure is erected with 30 layers of highly workable yet shape-stable mortar. The remarkable thing is that the mortar is fresh and unconfined, meaning each free-standing layer of material is gaining strength, as it cures, just fast enough to support on its own, the increasing weight of the other layers accumulating above it. The experiment was undertaken to demonstrate the feasibility 3D-priniting large structures using fresh unconfined concrete - formless concreting. An ABAQUS finite element model was used to simulate the test, and to insure structural integrity of the process.

Discover the team
Who’s behind this project
PL Projects Legacy
Discover the solution
Software used for this project
6
Project Timeline
Project Timeline
2016.05.17
www.contourcrafting.org