This study investigated characteristics of buckling load and effective buckling length by member rigidity of dome-typed space frame which was sensitive to initial conditions. A critical point and a buckling load were computed by analyzing the eigenvalues and determinants of the tangential stiffness matrix. The hexagonal pyramid model and star dome were selected for the case study in order to examine the nodal buckling and member buckling in accordance with member rigidity. From the numerical results, an effective buckling length factor of adopted models was bigger than that of Euler buckling for the case of fixed boundary. These numerical models indicated that the influence of nodal buckling was greater than that of member buckling as member rigidity was higher. Besides, there was a tendency that the bifurcation appeared on the equilibrium path before limit point in the member buckling model.
이 연구는 공간 트러스의 비선형 해석을 위한 해석기법의 수치해석적 효율성에 관한 것으로써, 좌굴 이후의 거동 파악이 가능한 복합 호장법을 제안하였다. 복합 호장범은 현 강성변수를 제어변수로 사용하여, 안정구간에서는 선취법이 첨가된 Secant-Newton법을 사용하여, 불안정구간에서는 가속법이 첨가된 호장법을 사용하는 방법이다. 해석기법의 효율성을 비교하기 위하여 제시된 수지예제에 대한 해의 정확성, 수렴성, 계산시간을 기존의 호장법과 비교하였다. 공간 트러스의 기하학적 비선형 해석에 있어서는 이 연구에서 제안된 복합 호장법이 기존의 호장법보다 수치 해석적 효율성이 뛰어난 것을 알 수 있었다.
This study investigated characteristics of buckling load and effective buckling length by member rigidity of dome-typed space frame which was sensitive to initial conditions. A critical point and a buckling load were computed by analyzing the eigenvalues and determinants of the tangential stiffness matrix. The hexagonal pyramid model and star dome were selected for the case study in order to examine the nodal buckling and member buckling in accordance with member rigidity.