Axial Compression Behavior of the High-Strength Concrete Squat Wall with Distributed Steel Tubes

Three high-strength concrete walls with distributed steel tubes (HC-DST squat walls) and three high-strength concrete-filled steel tubes (CFSTs) were tested to study the mechanical behavior of this type of squat wall. The strains of the steel tubes and the failure mode and axial force distribution of the squat wall were analyzed. Then, the mechanism behavior and the axial capacity formula for this type of shear wall were obtained. The rotation angle of the principal strain of the steel tube was between 3 degrees and 7 degrees. Therefore, the minimum principal strain and the maximum principal strain of the steel tube were replaced by the longitudinal compressive strain and the circumferential strain of the steel tube, respectively. The axial force of each part of the squat wall was distributed according to the vertical compressive stiffness before the peak load. Finally, the parametric analysis of the HC-DST squat wall was performed using the finite element method. The analysis results indicate that the axial capacity of the HC-DST squat wall increases with the increase of the confined area ratio or steel area ratio and decreases with an increase in the confinement coefficient.