Xiaodun Wang

Integral Analysis of Shallow Ellipsoidal Suspend-Dome with Elastic Restraint

Tianjin Baodi Gym is an engineering example of suspend-dome with shallow ellipsoidal shell with elastic restraints, supported on the lower reinforced concrete structure. The single model of the suspend-dome and the integral model that consists of the lower structure are established, and the static behavior, dynamic behavior and overall stability of both models are studied. Then a parametric analysis considering the effect of the rise to span ratio, the relative stiffness of the upper structure and the support stiffness is conducted, and the key parameter influencing the structural behavior is obtained. Results show that the effect of the lower structure on the static behavior of the suspend-dome is little, however, the support reaction can be significantly reduced. In addition, the integral effect has a great impact on the dynamic behavior and overall stability of the suspend-dome. Thus integral analysis should be carried out to guarantee the safety of the structure.

Analysis on the Seismic Performance of the Fully Bolted Diaphragm-Through Connections to RCFST

Based on the experimental results of fully bolted diaphragm-through connections composed of concrete-filled steel tubular columns and H-shaped steel beam, 3D nonlinear finite element models were established to analyze the mechanical properties of this new fully bolted diaphragm-through connection using ABAQUS. An analysis was conducted under cyclic loading. A method to estimate the bolt flip platform was presented and used to correct the hysteretic curves for the fully bolted through-diaphragm connections. The failure modes, load-drift, and stiffness degradation curves of the finite element analyses were found to be in good agreement with the tests results.

Experimental Study on the Mechanical Property of Visual Bolt-Ball Joint System

Grid structures with bolted spherical joints suffer impairment because of the “fake tightened-up” phenomenon. To prevent the “fake tightened-up” phenomenon, this study presents a new type of visual bolt-ball joint system that visually and effectively estimates the length of threads inserted into the bolt hole after adjusting the position of the fixed trip bolt and the location of the chute. The ultimate bearing capacity of the high-strength bolt and sleeve are studied via experiments. Results show that the failure section of high-strength bolts is the inclined section, which has a 60° angle to the direction of the screw, and a formula for calculating the ultimate bearing capacity is derived. Sleeves are compressed as their bearing failure is strength failure, which is due to yielding of the net section. A design method of the visual bolt-ball joint system is put forward according to the experimental results, and the safety of the visual bolt-ball joint is verified. Finally, the ductility and the fatigue performance of the visual bolt-ball joint are discussed in the paper.