|
||
|
|
||
The definition says that in order to obtain the maximal effect of the load from the influence line in a fixed section, the ordinate of the influence line in the x-coordinate is multiplied by the size of the load. In case of simultaneous action of several loads, e.g. in a load group, the effect is obtained as a sum of each ordinate value multiplied by the corresponding load size. The extreme can be both positive and negative. The positioning of each load group depends on the number of load groups.
In order to determine the position leading to the maximal effect of a group of concentrated forces, each force from the given group is positioned into every intermediate point. It means that in some positions, a part of the load group may be outside of the border of the structure.
For this configuration, the distance between the groups can be variable. In order to find out the critical position, the minimal and maximal distance of load groups must be specified.
For this configuration the distance between load groups is constant. The procedure applied is similar to one load group.
Note : The critical position can be formed by a group when some loads are placed outside of the structure. For the combination of asymmetrical loads, the program allows for motion of the mobile loads in two opposite directions, so that the effect of the asymmetry can be taken into account.