The Numerical Analysis On Interfacial Bonding Performance Between Steel Fiber Polymer Concrete And Old Concrete

The author research the steel fiber concrete's interface bonding properties and fracture properties,as a new pouring of concrete,with ordinary concrete,by different contents of polymer,silica fume adding to the steel fiber reinforced concrete.Also studied the effects of new and old concrete's interface bonding properties with different treatment on the old concrete interface,and the effects of new and old concrete's fracture properties with different debonding area.At last,the author simulat the fracture test with the finite element software.The study conducted the following test:(1)Concrete compression and bending test,we studied the effect of the different contents of polymer,silica fume for the steel fiber concrete;(2)Concrete core drilling pull-out test,we can measure the new and old concrete interface bond strength,and research the effect of the different contents of polymer,silica fume and the different treatment on the old concrete interface for the steel fiber concrete's interface bonding properties;(3)Three-point bending test of concrete beams,we studied the effect of the different contents of polymer,silica fume and the different debonding area for the concrete's fracture properties;(4)The numerical simulation of the three—point bending beam is established with the finite element analysis software—ABAQUS.We can compare the old and new concrete's fracture properties with different debonding area.Through the above experiment,it can get the following conclusions:(1)Silica fume have a significant effect on improving the basic mechanical properties of concrete,and in this test,we found the content of 9% is the best.Polymer don't significantly improve the mechanical properties of concrete,but it can increase concrete's flexibility;(2)When the polymer incorporated into ordinary concrete,it can significantly improve the interface bonding properties of concrete.But for steel fiber reinforced concrete,the impact is not obvious.Silica Fume can increase both ordinary concrete and steel fiber reinforced concrete's interface bond strength.The interface bond strength is maximum when applied the interface agent,grooving followed,without making the process is minimum.(3)Polymer can't improve the peak load and fracture toughness of concrete obviously during the fracture test,but silica fume can effectively increase the peak load and fracture toughness.For the different debonding area,when the larger of the area,the smaller of the peak load,the greater of the corresponding displacement,and the fracture toughness is decreasing;(4)The Finite element analysis and test results show a same trend,However,due to the part of the parameters used into the numerical analysis come from the test,another part is from the theoretical calculations,we get the results of numerical analysis has some difference with real results.