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Lane Distribution Factor

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Hi, quick question for our bridge experts:
I have a three-lane bridge that is 70' long and is supported by 5 longitudinal concrete girders.
I have run through AASHTO calculations to find the distribution factor for 1 girder so I can run my analysis to find the moments in the girder. My question is, since I have three lanes should I multiply the loads by 3?
For example i am using an HS-20 truck to find the moment envelope. The front axle is 8kips and 2nd & 3d are 32 kips. 
Should I load my beam by DF*8kips, DF* 32kips and DF*32kips?
Or should I use 3*DF*8kips , 3*DF*32kips and 3*DF*32kips? (For 3 lanes).

Note that i calculated the DF based on the "2 lanes or more" formula.


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