There doesn't look to be an easy way to repair that without some welding... Probably will have to remove the anchor and replace. Some anchor sets are linked together under the concrete by a bar to set the spread between them, so you may have to remove them both by cutting out a channel between them. You might be best served replacing both as the other might not be far behind. This means a concrete saw job, removal of the old, installation of new and pouring new concrete in the channel. Going with a bronze set may lengthen the life of the new set.