Axial compressive behavior of low steel-concrete composite walls with multi-partition steel tubes and concrete

Herein an innovative steel-concrete composite walls (SCW) with multi-partition steel tubes and concrete was proposed, and the axial compressive behavior for eliminating the overall stability was firstly investigated based on three axial compression tests. The test parameters included overall height and width-to-thickness ratio of single cavity. The test results validated that low SCW component obtained considerably large axial compressive strength and axial stiffness. Experimental observations demonstrated that under the axial compression, SCW specimens did not occur apparent overall stability, and developed the step-like multi-wave local buckling in the free-weld region of steel faceplate and core-filled concrete crush at the buckling location. Based on the test results, a refined finite element model (FEM) of SCW component was built and validated, and the influences of span-to-height ratio, faceplate thickness, concrete strength, and steel strength were evaluated according to the parametric analysis. The axial compressive strength and axial stiffness of the SCW component were enhanced significantly with increasing span-to-height ratio, steel faceplate thickness, concrete strength, and steel strength. Theoretical equations were proposed based on the SCW component mechanism and parametric simulated results, and the proposed equations offer accurate predictions on the peak axial compressive resistance.