A qualitative influence line is a graphical representation of the effect of a unit load or force on a specific point of a structure. It shows the variation of the response of the structure at that point as the load moves along the structure.
A qualitative influence line is a simplified version of a quantitative influence line. It does not provide numerical values for the response of the structure, but rather gives a visual representation of the overall behavior of the structure under the influence of a unit load.
The main purpose of a qualitative influence line is to determine the critical locations of a structure and to identify potential areas of concern for further analysis. It can also be used to make quick estimations of the overall response of a structure to a load.
A qualitative influence line is constructed by plotting the variation of the response of the structure at a specific point as the load moves along the structure. This is typically done by hand using a scale drawing or by using computer software.
A qualitative influence line is limited in its accuracy and cannot be used to determine exact values for the response of a structure. It also assumes that the structure is linear and elastic, which may not always be the case in real-world scenarios. Additionally, it only considers the effect of a unit load and does not account for the combined effect of multiple loads.
