Optimising 3D structure frames using GA

As it is known the first parameter for decreasing structure's expenses is the weight of the structure therefore, the designing process continues until the weight of the structure is reduced and strains & stresses are within allowable limit. Of course not only the weight of the structure but also its Topology plays a determining role. To design a structure usually after designing its form and the position of elements and loads we make the first guess for sections, and then analyze them to find the strains and stresses. The structure will be designed using the new stresses, and then the sections will be chosen to be analyzed and designed again. The process continues until the stains & stresses are allowable and minimum. The whole process can be done automatically using Genetics Algorithm. And all different sections are designed and chosen with the least weight (minimum) and allowable strains and stresses. In the present paper the procedure in which Genetics Algorithm relates with 3D frames considering joist vector, has been investigated.