What is the ruling on work that prevents a Muslim from performing Dhuhr prayer on time, requiring him to make it up throughout the work period, while his family refuses to look for work that allows for the performance of prayer?

If work after 'Asr prayer prevents one from praying Dhuhr, then missing the prayer and delaying it beyond its time without a valid excuse is among the gravest of major sins. One must pray at work during breaks, as prayer only takes a few minutes and does not require a specific place. If this is difficult, and work would be harmed by prayer, then one may follow the opinion of those who permit combining prayers due to a general need. So, if you are unable to perform Dhuhr at its appointed time, intend to combine it with 'Asr as a delayed combination (jama' ta'khir), then pray both of them during the 'Asr time.