Abstract：Pull-out tests were carried out on 24 specimens for the bond behavior
between geopolymer concrete and embedded steel bars, so that the bond failure
mechanism can be analyzed. Firstly, the influences of compressive strength and
splitting tensile strength of geopolymer concrete, type of steel bars, diameter of
steel bars, thickness of concrete cover and anchorage length of steel bars on the
bond behavior between geopolymer concrete and steel bars were investigated, and
then the bond behavior was compared with that between steel bars and ordinary
Portland cement concrete. The test results show that for those specimens with
anchorage length of 5d, the relative thickness of concrete cover c/d=3.67 shall be
the critical point of failure modes changing from the pull-out failure to the
splitting failure of geopolymer concrete. For the specimens with bar diameter of 14
mm subjected to centrally pulling out, the steel bar may yield before pulling out
of steel bar or splitting of concrete if the anchorage length is 9d. The prepared
geopolymer concrete exhibit similar compresside and split tensile strength with
that of ordinary cement concrete, but higher bond strength with steel bars. Based
on the test results, a constitutive model was established for the bond-slip
behavior between deformed bars and geopolymer concrete. The bond-slip curves
predicted by this model have good agreement with the measured curves of geopolymer
concrete specimens embedded with steel bars.
