I did not use my vote in the ballot because it would be unfair for me to vote for a strike and not take part. I believe that many may not have voted because they do not contribute to the LGPS pension scheme.
Curiously there have been occasions when governments have been formed by the aprty that recived fewer votes than the opposition! But nobody objected then.
Personally I think the proposed changes are a change of terms and conditions, which cannot normally be forced on employees. The increases in contribution are effectively a pay cut, which is illegal.