The distance between the tendons and the top surface at intermediate supports (their least top cover) is defined as generic data for the job in the Options dialogue box (Beam Definition tab > Post-tensioned > Options), together with the other parameters to be introduced to define the layout of the tendons.
Different parameters can be defined for the tendons when these are being introduced (Beam Definition tab > Post-tensioned > Introduce concentrated tendons or Introduce distributed tendons) or when editing a specific tendon (Beam Definition tab > Post-tensioned > Edit a tendon). Users can select two options in the Layout section of the dialogue boxes that appear when introducing or editing tendons:
- General job parameters
This option informs users of the parameters that have been defined in the Options dialogue box. By selecting it, the general job parameters can be assigned to the introduced or edited tendons. - Particular tendon parameters
This option opens a dialogue box where the layout parameters of the tendons that are being introduced or edited can be defined. By selecting it, the specific parameters are assigned to those tendons. The previous versions contained the option to define the Distance between the tendons and the top surface at intermediate supports. In the 2013.k version, this parameter has disappeared from the dialogue boxes which assign specific parameters and, now, the smallest top cover is defined when introducing the flexure lines of the tendons. The general cover for the whole job is still defined in the Options dialogue box (Beam Definition tab > Post-tensioned > Options).
In the new 2013.k version, when a flexure line is introduced, a dialogue box appears in which users can activate the option to Insert the distance to the top surface and define its numerical value for the flexure line that is being introduced. The tendons that cross this flexure line will adopt this value as their minimum top cover at that point. If the option to “Insert the distance to the top surface” has not been activated, the value of the cover will be that which has been defined in the Options dialogue box (Beam Definition tab > Post-tensioned > Options) in the parameter: Distance to the top surface in the intermediate supports.
Bearing in mind the introduction of the flexure lines now includes this possibility, two new options have been implemented in the “Pot-tensioned” dialogue box (Beam Definition tab > Post-tensioned), which allow for a flexure line, which has already been introduced, to be edited (Edit flexure lines of the tendons) or assign a selected flexure line to others that are selected individually or using a capture window (Assign flexure lines of the tendons).
By having the distance between the tendons and the top surface at intermediate supports as an option in the flexure lines box, different top covers can be defined for the same tendon in a more rapid and intuitive manner, which is useful for cantilevers or slabs with varying depths.
