I've been watching a Tetragnatha colony for several days. Lots of deposits of egg and covering blanket. Here the female is depositing a silk blanket. The weaving seems to have two components - depositing silk on the central mound and and then depositing a radial element. Not sure what the purpose of the radial element - perhaps lines to secure the blanket?
Depositing radial silk
Depositing central core silk
Video of depositing silk to the central core and radial stabilizers