When you create new structures using the button or with the menu Files | New | Mesh, once the form is found, we find ourselves with a screen like the one in the figure on the right. Obviously this membrane is usually not the entire structure.
The membrane could be anchored in existing elements: walls, masts, etc., but it’s very common that high points are supported by a set of masts and cables in line with the type of tensile structure. The low points are usually fixed directly to the soil or the floor, but also sometimes have a structure of masts and cables in smaller size.
To facilitate the work of creating these tripods, WinTess3 provides an option through the menu Other | Create tripod.
Once you have selected this menu the program asks that we point out the node we are going to implement a tripod. In our example, we are going to start with the highest point. Thus we press the mouse on the highest point to display the window for creation of tripods. In the title of this window we can see the number of node selected.
Firstly, we will size our tripod. We need the height (vertical) of the mast and the guyropes. If the height of these three elements were different in reality, then we will modify it later. The numeric data requests are:
Vertical height of the elements of the tripod
Inclination of the tripod. This value can be positive, zero or negative. The positive value corresponds to the graph and a negative value is very rare.
The inclination of the guyropes. This value can be positive, zero or negative. The positive value corresponds to the graph and a negative value is very rare.
Separation between the guyropes. This value can be positive or zero, but not negative. If the value of C is zero, the program assumes that there is only one guyrope.
- Only the mast, no cables
Finally, if we mark the Only the mast checkbox, no guyrope is created.
Obviously, we can subsequently modify any data of the tripod that has been generated.
A tripod on the ground has a main direction. We are going to consider that the orientation of a tripod is one marked by the direction of a vector that depart from the projection of the upper node to any other point.
First, we can assume that the tripod is oriented along one of the principal coordinate axes X, Y (always on plan). If so, we use the first 4 option buttons in the mast direction frame. However, it is more likely that we want to orient the tripod in another direction. To do this the program requires a point which will serve as a reference.
In our example, the high point is 98, therefore the most logical thing is that the reference point is one of the ranging from 98 to 4.
Suppose that we use 4, write it in the appropriate box and click the OK button. You can also mark it directly with the mouse on the main screen.
With appropriate data, H,A,B,C, we have created the tripod. The program automatically predimensions the mast and the guyropes. The user is required to verify that this predimensioning is correct.
We can then modify any parameter we don’t like.