| With the development of the national economy, large-scale steel industrial workshops have been built in all over the country. The research of exposed steel column base becomes more and more important. In order to make sure the affect of anchor arranged modes to the exposed mechanical properties, it is necessary to build a more complete column base mode including the anchor bolt. In this paper, established the M27 (model I) and M36 (model II) anchor column base model according to an existed test before making the numerical calculation and the theoretical analysis method of the column base clear. First of all, impose column base the same cyclic loading to analysis its mechanical behavior; secondly, introduce two kinds of anchor bolt pretension and compare the impact of the construct before and after the pretension. Reach the following major conclusions:1. The two kinds of the steel column are similar to the properties, plastic deformation has not yet occurred.2. The two kinds of the base plate are similar to the properties, as the steel columns, no plastic deformation occurred.3. The two kinds of the column base yielded caused by the bolt, as the steel column and base plate did not yield, the anchor bolt forces becomes a major factor in performance.4. The outer two bolts of Mode I appeared necking phenomenon reaching the limit strength, the inside of the two bolt did not appear obvious necking phenomenon; model II has larger cross-sectional, it has less stress than bolt model I.5. The deformation of the two column bases are the same after pretension, steel columns and base plate still not reach yield strength, the destruction of column base is controlled by bolt damage. However, the pretension optimizes the performance of the bolt, makes the stress increase more slowly and evenly, increases the plastic deformation of the bolt and then makes the properties more rational and deformation.6. The connection of the base plate and anchor bolt is more closely because of the pretension, it enhances the integrity of the column base and initial bending stiffness, slows down the separation between base plate and foundation beams, is good for the whole structure stability.7. When both satisfy the mechanical properties of the connection, mode II uses fewer bolts, facilitates the construction and can achieve the purpose of reducing the steel quantity.Therefore, when the bolt damage becomes a main controlling factor of the column base failure, it can be taken to increase the bolt diameter and scatter the arranged of the bolt in the base plate, make the design more rational and economic. |
