Precast concrete joist composite system

A precast concrete joist composite system, comprising:

• (a) support means;
• (b) at least first and second space apart precast concrete joist members supported at their respective ends by said support means, each of said joist members having a concrete portion, said concrete portions comprising respective end faces, said joist members comprising at their said end portions respective projecting structures that have first parts anchored in said concrete portions of their respective joist members and second parts extending from said concrete portions, said joist members including end faces, said end faces having respective portions thereof that slope downward and away from said concrete portions, said concrete portions comprising respective top surfaces;
• said projecting structure second part being at least partly disposed on said support means;
• (c) at least a first pan element that is disposed at said end face, a first part of said pan element being disposed over said top surfaces of said concrete portions and a second part thereof disposed over said sloping portions of said end faces;
• (d) a decking element disposed over the respective said top surface of said first and second joist members and spanning the space between said joist members and part of said first pan element.