An apparatus comprising a composite elongate member, a channel, and a number of composite structures. The composite elongate member has a side configured for attachment to a surface of a structure. The channel is on the side and extends along a length of the composite elongate member. The number of composite structures is configured for placement in the channel and configured to attach a portion of the side of the composite elongate member to the structure. A composite structure in the number of composite structures comprises layers having different orientations selected to increase a capacity of the composite elongate member to withstand forces that pull the composite elongate member away from the structure.