SSRS - Adding Page Break

To add page break to a large result set (http://social.msdn.microsoft.com/Forums/sqlserver/en-US/276acd62-49e7-41ad-a50e-7e4b97e44dcc/tablix-paging-in-ssrs): 

In your scenario, you want to display 10 records in each page, we can achieve it follow the steps below.

a.      Click the Details group in the Row Groups pane.

b.      From the Tablix member Properties pane, expand “Group”-> “PageBreak”.

c.       Set the “BreakLocation” to “End” and set the “Disable” property to the expression like below (Disable pagebreak on export):
=IIF(Globals!RenderFormat.Name = nothing, IIF((rownumber(nothing) mod 30) = 0,false,true), true)