Selected Answers

From Thomas McMinn of Structural Investigations, Inc. on March 4, 2016:
My answer assumes long-term ownership. The answer ...read more My answer assumes long-term ownership. The answer would be different for short-term. Seaside balcony slabs are one of the more severe service environments for reinforced concrete. For these slabs, I generally recommend cathodic protection (CP) for new construction. For existing structures, retrofitting CP is more expensive and disruptive to building operations. In the long-term, however, the cost of retrofitting CP is generally justified. It is important to be aware that active CP can cause hydrogen embrittlement tendon problems if the slab is post-tensioned (PT). I have used passive CP on PT slabs with good success.

From Michael Halliwell of Thurber Engineering Ltd. on March 4, 2016:
Although I don't know the specifics about the loca ...read more Although I don't know the specifics about the location, any time you get salt and concrete mixing, you have to take into account the effects the salt can have. A reactive silicate may help, but it won't stop the chloride-related deterioration of the reinforcement once cracks develop. For the cost and relative ease of putting in cathodic protection during construction, I'd say it is worth it to prevent the concrete version of the Berkeley balcony collapse.