Spanish to English Tech/Engineering Construction / Civil Engineering excavation

se han continuado los trabajos de excavación con la ayuda de palas martillo, palas de balde y camiones, logrando alcanzar los niveles especificados.

a plot of land is being excavated in preparation for foundations being laid. i imagine this is some sort of jcb-type machine but i'm not sure of the actual term. on the jcb website i did come across a section of "hammers" which look more like big drills but how can i specify that they're "big" hammers? (cos the translation sounds a bit silly if i just use hammers and buckets!). this text is from South America by the way.

thanks