Mat Foundation Issue

Hello forum,

I have built a large mat foundation with dead and operating loads in the x, y and z directions.  I have entered the y-direction loads negatively to reflect a downward force.  The mat foundation is supported with piles.  I used the pile position table under the pile layout leaf to place my piles.  When I analyze the model, my pile reactions do not equal the downward force which is being applied to them.  Does anyone have any ideas on what I might be doing wrong?  I can get into more detail if anyone might have any ideas on this boondoggle.  Thanks!!

JP