You are here

Mesoscale Model Capability Informed by Cemetitious Composite Microstructure

Description:

TECHNOLOGY AREA(S): Materials 

OBJECTIVE: To develop computationally effective software for the prediction of concrete properties and their evolution in time based on constitutive materials. 

DESCRIPTION: With increased frequency, military personnel in the field are required to build structures with concrete materials whose properties are not known and for which the available technical literature is insufficient to estimate these properties. This applies to a wide range of concrete mixes, from low-quality concrete manufactured from in-situ or indigenous raw material components to ultra-high-performance concrete designed for high-end applications such as the protection of sensitive and high value structures (e.g. embassies, command and control buildings, etc.). Hence, there is a need for computational tools that allow the prediction of the mechanical properties of concrete directly from the basic components used in the mix design through simulating the generation and formation of concrete. These tools need to be accurate enough to be used in practical design applications but, at the same time, might need to be simple enough to be operated by personnel in the field. By leveraging recent accomplishments and published research, the US Army seeks the further development of the foundation for such tools within the computational framework of finite element and meshfree methods [1], which have been validated in the simulation of concrete and concrete structures [2, 3, 4] subject to blast and penetration, as well as in the simulation of concrete subject to long term deterioration phenomena [5]. The desired product should be capable of receiving the mix design parameters for cements, cementious materials, and aggregates via a script or GUI based interface, and output model parameters for continuum level material models in meshfree and finite element codes. This effort will be limited to the concrete material at the meso-scale, and is not expected to include reinforcing bar, but may include fiber reinforcing. 

PHASE I: Develop a framework for a microscale model informed directly by hydration simulation.Demonstrate this approach on a model system. Identify an approach to computational optimization to achieve desired performance characteristics to be demonstrated in Phase 2. Deliver a technical report including microscale model development, demonstration on model system, and conceptual approach for optimization tied to multi-scale modeling framework. 

PHASE II: Develop an integrated approach of linked hydration, microscale, and multi-scale modeling. Develop an optimization routine to achieve desired performance characteristics. Demonstrate this approach on a variety of model material systems representing different types of concretes. Compare the predicted material behavior at all length scales and the continuum level response with experimental observations. Demonstrate linkages between a multi-scale enabled approach to directly inform continuum level constitutive model calibration for meshfree and finite element codes. Deliver updated software package with integrated microscale models and optimization algorithms. Deliver technical report showing use of these tools on variety of model concrete systems. Deliver training for ERDC computational mechanics team and software for integration into HPC platforms. 

PHASE III: Develop a fully integrated software package for non-expert use with integrated optimization tools to achieve target/goal performance characteristics with microscale models and multi-scale framework running in background. Software should provide outputs that can directly calibrate continuum level material models for weapons effects codes. Deliver integrated software system, technical report of finding including demonstration of technology on real work problems in blast, penetration, and quasi-static loading under a variety of conditions (i.e., study boundary value problems with experimental validations), transition software tools to HPC environment, and provide training for ERDC users. 

REFERENCES: 

1: G. Cusatis, D. Pelessone,A. Mencarelli. Lattice discrete particle model (LDPM) for failure behavior of concrete. I: Theory. Cement and Concrete Composites, 33(9), pp.881-890. 2011.

KEYWORDS: Cement Hydration, Concrete Modeling, Indigenous Concrete, Material By Design, Material Optimization, Multi-scale Modeling, Ultra-high Performance Concrete 

US Flag An Official Website of the United States Government