(Portland, OR) -- Closures are planned on I-205 and I-5 starting this weekend. Friday at 11 p.m., I-205 northbound will close over the Abernethy Bridge for concrete pouring. It'll re-open Saturday morning when the work is complete. Then, I-5 will close in both directions Saturday at 10 p.m. for installation of a sign bridge near the Oregon Convention Center. It'll reopen around noon Sunday. Next week, there will be overnight closures of the I-5 Interstate Bridge for inspections.