If you have the file locally, then use install.packages() and set the repos=NULL:
install.packages(path_to_file, repos = NULL, type="source")
Where path_to_file would represent the full path and file name:
- On Windows it will look something like this:
"C:\\RJSONIO_0.2-3.tar.gz". - On UNIX it will look like this:
"/home/blah/RJSONIO_0.2-3.tar.gz".