Analysis of Axial Compression Performance of SRCFT Short Columns with Void Defects

Abstract:

In order to explore the axial compression performance and failure mode of steel reinforced concrete filled steel tubular (SRCFT) short columns with initial concrete imperfection, a finite element model of SRCFT short columns with initial concrete imperfection under axial compression is established, the parameters of SRCFT short columns with different gap radio, steel tube strength, steel tube thickness, concrete strength, steel strength and steel type are analyzed, and the axial compression perfor-mance and failure mode of SRCFT short columns with initial concrete imperfection are discussed. The results show that the SRCFT short columns with initial concrete imperfection increase with the increase of steel tube strength, steel tube thickness, concrete strength, steel strength and steel type. The specimens with annular debonding defects exhibited ultimate bearing capacity reductions from 19.11% to 20.91% when the debonding rate increased from 1.1% to 3.3%, while those with spherical cap debonding defects showed capacity decreases from 8.74% to 15.77% corresponding to debonding rates progressing from 2.2% to 6.6%. That is, with the increase of the gap ratio, the ultimate bearing capa-city of the specimen decreases and the axial compression performance is weakened. It can provide a theoretical basis for the study of SRCFT short columns with initial concrete imperfection.