install partclone by :
apt-get update
apt-get install partclone
combine and extract clonezilla gzip file to img file :
cat sda1.hfsplus-ptcl-img.gz.a* | gzip -d -c | partclone.restore -W -o /tmp/sda1.img -L /tmp/partclone.log
image extracted can browse with hsexplorer:
for windows browsing mac os x hfsplus image
reference link : http://www.catacombae.org/hfsexplorer/