Shock Wave Propagation in Cementitious Materials at Micro / Meso Scales

نویسندگان

  • Ram Mohan
  • M. Nelms
  • A. M. Rajendran
چکیده

Shock Wave Propagation in Cementitious Materials at Micro/Meso Scales Report Title Shock wave response of heterogeneous materials like cement and concrete is greatly influenced by the constituents and their statistical distributions. The microstructure of cement is complex due to the presence of unhydrated water, nano/micro pores, and other hydrated and unhydrated products, such as the C-S-H gel, tri-calcium silicate, di-calcium silicate etc. The evolved microstructures at different degrees of hydration are captured using a suite of software that explicitly modeled the chemical compositions of various constituents and their byproducts for a water/cement ratio of 0.4. An evolved microstructure of 50x50x50 micron3 volume of Portland cement product was modeled as a representative volume element (RVE) through a general purpose finite element code, ABAQUS®. The heterogeneity induced shock decay phenomenon under compression in this 50-micron size cube due to an OFHC Copper flyer plate impact is analyzed. Conference Name: 19th Biennniel Conference of the APS Topical Group on Shock Compression of Condensed Matter Conference Date: Shock Wave Propagation in Cementitious Materials at Micro/Meso Scales M. Nelms, A.M. Rajendran, W. Hodo, and R. Mohan Department of Mechanical Engineering, University of Mississippi, University, MS U.S. Army Engineer Research and Development Center, Vicksburg, MS Joint School of Nano science and Nano engineering, North Carolina A&T State University, Greensboro, NC Corresponding author: [email protected] Abstract. Shock wave response of heterogeneous materials like cement and concrete is greatly influenced by the constituents and their statistical distributions. The microstructure of cement is complex due to the presence of unhydrated water, nano/micro pores, and other hydrated and unhydrated products, such as the C-S-H gel, tri-calcium silicate, di-calcium silicate etc. The evolved microstructures at different degrees of hydration are captured using a suite of software that explicitly modeled the chemical compositions of various constituents and their byproducts for a water/cement ratio of 0.4. An evolved microstructure of 50x50x50 micron volume of Portland cement product was modeled as a representative volume element (RVE) through a general purpose finite element code, ABAQUS. The heterogeneity induced shock decay phenomenon under compression in this 50-micron size cube due to an OFHC Copper flyer plate impact is analyzed. Shock wave response of heterogeneous materials like cement and concrete is greatly influenced by the constituents and their statistical distributions. The microstructure of cement is complex due to the presence of unhydrated water, nano/micro pores, and other hydrated and unhydrated products, such as the C-S-H gel, tri-calcium silicate, di-calcium silicate etc. The evolved microstructures at different degrees of hydration are captured using a suite of software that explicitly modeled the chemical compositions of various constituents and their byproducts for a water/cement ratio of 0.4. An evolved microstructure of 50x50x50 micron volume of Portland cement product was modeled as a representative volume element (RVE) through a general purpose finite element code, ABAQUS. The heterogeneity induced shock decay phenomenon under compression in this 50-micron size cube due to an OFHC Copper flyer plate impact is analyzed.

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تاریخ انتشار 2015