Syed

Can you please make me understand the process of movement of the chair lifts. How it is controlled? Is there a single cable that starts from one tower and takes a round over the rest of towers with pulley action, i-e, the single cable becomes the part of both Up-Way movement and the Down-Way movements? Or there are two independent movements going on, i-e, the Up-Way and the Down-Way separately? If two separate movements going on (involving the two opposie set of towers) then within each system where are those pulleys located that turn the motion of cable by 180 degrees? OR Will those pulleys be apart from both the towers? I just want to think about the transfer of lateral load of the chair lifts to the towers during motion as well as at static conditions. Of course slope is one of the factor that will generate a component of lateral load but apart from it, is there any pulley reaction transferring to the columns? Regards

Dear Engineers, Without going into any in-depth design I have just checked roughly the steel column size required for the stability concern, i-e, the size required to keep the slenderness ratio (k l/r) within 200, it comes out to be around 36 X 36 inches X 1/2 inch thickness, which gives the slenderness ratio of 187. I am not sure about the thickness requirement at this stage because it will also be governed by the fulfillment of strength requirements, i-e, the design load-moment interaction. I believe that every code has the stability requirements (The slenderness limitation), depending upon the importance of the compression member itself, it may sometimes be less than 100 in some codes, better to check with the code upon which the design is being carried out. I took the height of column as 150 feet and assume "k" as 1.5, which may increase depends upon the boundary conditions at column top. I suggest that a truss type of column be selected and also to keep in mind the workability / Installation process while designing these columns. Wish you good luck