The application of magnesium oxide concrete in the formwork structure of the cut and cover method has enriched the engineering application scope and practical experience of magnesium oxide expansion agent It is proposed that the measures and technical routes of "temperature control shrinkage compensation" shall be adopted for the ultra-long, seamless and large volume concrete, and the measures of intermittent magnesium oxide expansion reinforcement belts are applied. At the same time, the calculation formula of equivalent temperature difference and equivalent length of magnesium oxide expansion stress is proposed, which provides reference for similar projects.