mr.pradyumna from vskp has seen a stone similarly connecting the tracks to the platform yesterday at pendurti station...but as per his version,it was a stepping stone to platform...hence to rediscuss this boring topic i have reopened it...till now,the accepted logic is that it helps keeping tracks at a safe distance from the platforms and prevents lateral movement(swaying)to some extent...used at platforms to prevent the body of trains to rub against the platforms or to prevent injuring a passenger standing very close to the tracks...