In complicated wharf engineering, 3D-based design and FEM not only enhance performance of 2D drawing, and improve efficiency, but also offer strong reference to structure analysis and optimization. In order to better connect autoCAD drawing to FEM calculation and enable FEM file to communicate on the internet, FEM is combined with WebGL and a set of programmes for 3D design and analysis is developed. The programmes are run on Autocad and Adina platform, and start from 2D drawing, build FEM files semi-automatically, and the stress and temperature field are derived. The postfile is further processed so that we can display contour plots and execute interactive operation on internet. The whole set of technical solution integrates design, calculation and display. It is tested and verified on a project with satisfactory results.