Here are some examples of the kind of long dog trailers some European countries are opting for. Scandinavia and the Netherlands allow these kinds of combinations up to 60 tonnes and 25.5 metres in length. Outside of areas where these trucks are allowed, the combinations are broken up into a semi and a rigid.
The design echoes the kind of long dog trailers which have started to appear on the roads around our major capital cities in recent years, using PBS rules to get high mass tipper and dog combinations. However, the short draw bars used in Europe would suggest compromised stability in the design. Electronic stability control is obviously trusted to do the job and keep the trucks under control.