Theory Of Space Stability Of Open Thin-Walled Columns And The Checking Computation Of Column Curve Based On It

Based on the three new supposition and the tow new mechanical tools: moment vector and radius vector , the warping theory introduced the analytical method of the rotation of a cross section around a fixed axis, so as to make the space stability of the thin-walled member complanate and one-dimensioned. According to the principle of the rigid body motioning, the theory composed the bending by the two principal axis and the rotation around the shear center to a rotation around a new point. Accordingly, it unified the traditional three-dimension analytical method to the new one-dimension analytical method, and made the analysis of the space stability more succinct and simple.The paper introduced the space stability theory based on the method of the rotation of a cross section around a fixed axis of the thin-walled member, and made some simply discursions . According to the theory, a programme was worked out to analyse [-shaped, T-shaped and L-shaped axes columns. Using the results of the programme, the paper has made the graph of the critical force changing by , and furthermore analysed the characteristic of the thin-walled members' space stability.Introduced the second order analysis of the thin-walled members based on the theory of the rotation of a cross section around a fixed axis, and discussed the general methods of the loading capacity and the space stability coefficient for the thin-walled columns. Used a programme, a large amount of space stability coefficient of T-shaped and L-shaped axes columns with a initial bend was computed to gain the curves of the columns. The procedure of the computation behaved the simplification and the convenience of the method. At the same time , a way was put forward to optimize the section of the thin-walled columns. After the comparison of the stability checking computations and the section categorised situation both at home and abroad the current standard, some problems was discussed in the standard of our country. Contraposed these questions, the paper computed the space stability coefficient of some general T-shaped and L-shaped sections and all the sections of T-shaped ,L-shaped and 2-angle iron T-shaped in the formed-steel-table, and worked out the curves. According to the comparison of the curves the paper got and the curve in the standard, some simple conclusions was putforward to discussion the section categorized situation of our country. Some advices may be referenced by the redaction of the standard. At the same time, the results farther testified the correctness of the space stability analytical method for the thin-walled columns the paper recommended.