In the GUI mode: Open the appropriate waveform file and then choose appropriate format from menu File | Export | Waveforms
In the Batch mode: Use the the appropriate command to convert like asdb2lst, asdb2vcd etc.
The following text formats are supported:
WAVES-compliant test vector files (*.vec). This format is briefly referred to as VEC.
Regular VHDL code with process statements generating equivalent signal waveforms. This format is briefly referred to as VHS.
Verilog Initial Block format (VER)
Value Change Dump and Extended Value Change Dump format (VCD)
Tabular format (EXP)
List file format (LST)
Chip Express Test Vector format (CTV)
Files of the VEC, VHS, VER, or VHR format can be used during the generation of HDL test benches.