Slogging

Erecting-shop work was always hard and slogging, so that at the end of a 9¾ hour day there were not many who felt inclined for much more physical activity.

Source: wiktionary

The heat of the fire, the steam which arose from the dampening water, the hard slogging at the white-hot metal of the links, and the continual pulling of lengths of chain, were calculated to put a test on the strongest of men, and often on hot summer days they had to be sent home, for the work became unbearable.

Source: wiktionary

Washed-up jerry cans and bits of lumber wriggled at the water's edge, amid the sewage and the sloggings of occasional fishermen and the spreading wake of a Vietnamese patrol boat.

Source: wiktionary