A connection system (10) for joining sheets (11) together along adjacent edges (13) thereof at connection (20).. The sheets (11) may comprise tarpaulins used as a protective covering for a stockpile, such as a grain stockpile. The connection (20) is configured to facilitate progressive interconnection of the adjacent edges 13 in a manner similar to that of a zipper. The connection (20) comprises two male locking strips (21), and a central female locking strip (23). The male locking strips (21) are provided on the respective edges (13) of the sheets (11) and are adapted to be releasably engaged with the central locking element (25). In this way, the central locking element (25) interconnects the two male locking strips (21). To facilitate this interconnection, the central female locking element (25) defines two opposed longitudinal jaws (31) for receiving the male locking strips (21). The central female locking element (25) also defines the locking channel (27) between the two opposed longitudinal jaws (31). The locking channel (27), upon progressively receiving the locking key (29), is caused to expand laterally and thereby cause the two opposed longitudinal jaws (31) to close about the male locking strips (21) and captively retain them in position. The connection system (20) further comprises apparatus (50) for assembling the connection (20). The apparatus (50) is adapted for movement along the female locking element (25) to progressively insert the male locking strips (21) into the respective longitudinal jaws (31) and to progressively insert the locking key (29) into the locking channel (27). The apparatus (50) is typically self-propelled and operable remotely under the control of a user.
