Research on the dynamic compressive test of highly fluidized geopolymer concrete

摘要

Slag and fly ash were used in the fabrication of geopolymer concrete (GC), sodium hydroxide (NaOH, NH) and sodium carbonate (Na_2CO_3, NC) were used for slag and fly ash activation, then highly fluidized C30 GC was prepared. φ100 mm SHPB apparatus was improved by the pulse shaper technique, and the dynamic stress equilibrium and nearly constant strain rate loading were realized. Based on this, the dynamic compressive mechanical properties, including strength, deformation and energy absorption property, of GC were tested, in addition, the mechanism of dynamic properties of the GC was primarily analyzed. The results indicate that, dynamic compressive mechanical properties of GC exhibit strong strain rate dependency; dynamic strength increase factor increases approximately linearly with the logarithm of the average strain rate; the peak strain increases firstly and decreased later with the rising of stain rate, 66.7 s~(-1) is the critical strain rate between impact toughness and impact embrittlement; from an energy perspective, the correlation between specific energy absorption and stain rate is obvious and the equation type is binomial curve.