To loop a wiggle, you can create two wiggles with similar properties, one reversed in time by using the fifth wiggle function parameter, and blend their output value trough a linear interpolation.
The procedure is fully explained here :
The resulting piece of code can replace the simple
wiggle() formula of any expression.
freq = 1;
amp = 110;
looptime = 9; // in seconds
t = time % looptime;
a = wiggle(freq, amp, 1, 0.5, t);
b = wiggle(freq, amp, 1, 0.5, t - looptime);
linear(t, 0, looptime, a, b)