When you say not having any luck what do you mean? Do you get an error message, does it cause problems? What is the exact command you are using, on what OS? – GdDFeb 28 at 15:39
options are case sensitive, -t means format of timestamp and I guess you want to use -T that set the format of output. Depends on what kind of data you would like to dump, e.g., http host, tshark -r file.pcap -T fields -e http.host should be what you are looking for.