Just encountered this beta version of Swift Calcs, which looks very promising. It is designed by engineers for engineers and allows you to perform your engineering design and analysis calculations using conventional human readable mathematical notation. At the moment it is free of charge and can be accessed through this link: https://www.swiftcalcs.com.
For more information, check out the Swift Calcs blog. Should you know of any other interesting software for civil and structural engineers please leave link in the comments section below.