Experimental study on dynamic direct tensile mechanical properties of mortar-granite ITZ
JIANG Wei1，LU Yubin1，JIANG Xiquan2，DUAN Junzhou1
(1. Key Laboratory of Testing Technology for Manufacturing Process of Ministry of Education，Southwest University of Science and Technology，Mianyang，Sichuan 621010，China；2. Army Artillery Corps Air Defense Academy，Laboratory of Dynamics of Advanced Materials，Hefei，Anhui 230031，China)
Abstract：The interfacial transition zone(ITZ) is considered to be the “weakest link” of concrete structures. To study the effect of different strain rates，aspect ratios，and surface roughness of the aggregate on the dynamic tensile properties of the mortar-granite ITZ，a large-diameter(? 75 mm) split Hopkinson tensile bar(SHTB) device was applied in dynamic direct tensile tests to mortar-granite composite specimens. Experimental results showed that the tensile strength of ITZ increased with the growth of strain rate. The tensile strength of ITZ is strain rate sensitive，which is closely related to the surface roughness of aggregates. The average tensile strength of ITZ decreased with the increasing of surface roughness of aggregates. Under the same loading pressure，the average tensile strength of ITZ declined significantly with the growth of aspect ratio，and the descent range was diminished with the increasing of aggregate surface roughness.
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2018, Vol. 37 
