Thank you for contacting Ask Extension.  There are many possibilities for this problem. 

1. Maple trees have thin bark, which makes them susceptible to frost cracks, especially on the south side of the tree. Frost cracks are vertical cracks in the stems of trees. These happen when there are rapid temperature fluctuations. On warmer, sunny days in the winter, the bark will warm up, which causes the cells to expand in the bark and wood directly below the bark. Then if temperatures drop very quickly, the bark cools and contracts. The wood under the bark does not cool as quickly, causing the bark to split. 

2.  Maples can develop cankers or other diseases that cause bark deterioration. Canker diseases often manifest as sunken areas or lesions on the bark, which may eventually lead to bark falling off. In the photos you included I do not think I see any cankers, 

3. Sooty bark fungus is caused by cyptostroma corticale. it makes its way into a maple's heartwood. Once it reaches the core of the tree it spreads up and down the trunk eventually traveling outwards to the bark. When it arrives to the bark layer it will kill the bark and produce a dark sooty-looking spore-producing mass under the bark.  The black streaks I see in the photo make this a real possibility. 

For much better assistance I would do one of the following: 

1. Get a professional arborist, particularly if it is in proximity to your home.

2. Take a scraping and a piece of the bark to your county extension office for their opinion and possibly have the specimen sent to the OSU lab.

3. Contact your urban forester from district 5, of the Department of Natural Resources.  She might be able to look at the photos and give you better diagnosis and treatment.  Depending on their time and availability they might be able to visit the trees. 

Region 5: Wendi Van Buren / Email
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2702 E. Kemper Road
Sharonville, OH 45241

This is an extension fact sheet that you might be interested in reading. 

Shedding, Peeling, and Splitting Bark on Shade Trees | Yard and Garden

 I hope you are able to find the problem.