Shop Drawings are the piece of paper related to a particular details which is enlarged and given for better understanding of the details.
Shop Drawings in Civil Engineering mostly related with as built drawings prepared on site by Civil Engineers for things which are either not executed as per drawing or drawing was not available for constructed work.
Example: Customer makes a changes in electrical work which is not given on drawing, Site engineers makes a shop drawing for how he routed electrical lines in walls and floors in particular flat, this shop drawing helps in ensuring no major damages during further changes or relating it with other services.
Construction drawings are provided by design/ Architecture team having all details respect to design or Architectural view while Shop drawings are the detailing of construction drawings pertaining all details for Actual construction/ Fabrication at site and prepared by detailer. Shop drawings are mostly required in steel structures as construction drawing mostly have details of members and it location while detail drawing/ Shop drawing have details of all members and its connection details based on construction drawings.