EXPERIMENTAL RESEARCHES OF A SUSPEN-DOME STRUCTURE WITH ROLLING CABLE-STRUT JOINTS

摘要

Rolling cable-strut joints are applied in the suspen-dome structure to diminish the friction loss in the process of tensioning the cable and to guarantee the global stability of the structure. A 1:10 scaled-down model of the suspen-dome structure, which is adopted in Chiping Stadium, was built. Firstly, the prestressing optimization mathematical model of the suspen-dome structure was derived based on the principle of optimization of the finite element analysis software ANSYS, and the prestressing optimal design value of the 7 circles of cables were calculated using ANSYS. Secondly, tension test was conducted on the scaled-down model. Cable force values of each circle during the tension process were tested using the new cable force measurement device invented by the research group, namely the cable force measurement device based on clip anchorage connection. Then, full-span loading test and half-span loading test were conducted respectively on the suspen-dome structure exerting prestressing, and the displacement of the key nodes during the loading process were monitored using the new intelligent laser tracker, the measurement accuracy of which is 0.01 mm. At last, A comparative analysis of the static performance of the suspen-dome structure and the single-layer reticulated shell without the tensegrity system was described in the paper. The static performance of the suspen-dome structure with rolling cable-strut joints was studied systematically. Experimental results indicate that the pretension of the outer circle of cable has the greatest influence on the suspen-dome structure, and pretensions of lower circles of cables influence each other, which, however, differs in terms of the influence degree according to relative locations of cables; the stress distribution of members in the upper part of the suspen-dome structure is similar to that of the single-layer reticulated shell under full span loads, which mainly shows compression in diagonal bars and circumferential bars near the inner ring and tension in bars near the outer ring. However, the maximum compressive stress and the maximum tensile stress of circumferential bars and the maximum defection of the suspen-dome structure were reduced by 15.0%, 43.7% and 51.5% respectively when compared with those of the single-layer reticulated shell. Therefore, due to the introduction of the tensegrity system in the supen-dome structure, the static performance of the suspen-dome structure is superior to that of the single-layer reticulated shell obviously.