Why does a stranded steel rod lose strength compared to a solid rod?

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suryanarayan
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Consider a steel rod of diameter 'd'. If the same rod is broken up into strands and arranged parallel to one another so as to form a new rod of the same diameter 'd' ,Which will have a higher load bearing capacity?. Instead of being arranged parallel , If they are made into a rope of similar diameter 'd' , Will the results still be the same?
Something related to this was taught in our class today and the teacher had said that the fiber one would have more strength but he did not elaborate.So I tried searching the internet but all could find was that ,if they are arranged in parallel,due to a reduction in area,they would be weaker than the solid one.But I am not sure whether this is correct as this was a random post answer and I couldn't find anything on the rope version of it.Please clarify this for me
Please give reasons as well.
Thank you
 

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ok this is just a guess but i have always been told that "a change is only as strong as it weakest link" if one could look at everything from that point of view the solid rod would be stronger than the rod made of smaller pieces but the rope like one would think could be a little stronger because it would be woven and interlaced so one strand would not have to bare the load of the hole length it would be broken up every time another strand crosses it and if one strand broke the others would be there to take up the slack even throw the rope would become weaker at that point i guess it would come down to where you are stressing the rope, rode, bars and how long of a length of one that you are using to stress it and of course the material that you would be using
 
suryanarayan said:
Which will have a higher load bearing capacity?
It depends on the orientation of the load application.

In tension it will probably be stronger because the fibres can share the load, if any fibre breaks the break will not spread. A crack on the surface of a solid rod will move through the entire rod resulting in total failure.

If the load was applied to the side of the rod, the fibre rod would flex long before the solid because the fibres could slide against each other.