electrical problem to fuel pump

i have a 1990 full size jimmy 5.7 tbi and having problems with the fuel pump
i have had a new fuel pump put in, electrical checked and new computer put in, my problem is that if there is any large or sudden vibrations in the road (or field) that i might been driving on the fuse that completes the circuit for the pump shuts blows... i have had it checked numerous times by different people and they cant find anything, i was just wondering if there's any random switches that might be kicking out or safety device problems going on... any ideas?
thanks