## 1 Introduction
Theoretical analysis, on the basis of the existing theoretical studies, can be a more in-depth analysis of the soil change mechanism, and through the in-depth study of the formula, can be a more suitable calculation formula. In order to further save underground space in the important areas, the pipes are arranged vertically in two layers. However, there is less research on the deformation features of the soil induced by the construction of vertical two-layer pipe jacking. The main ones are [PERSON] et al. [18], who studied the vertical deformation feature of silty clay caused by two-layer pipe jacking construction and the soil pipe crossing is relatively simple in this research. [PERSON] et al. [19] also analyzed the sand layer ground settlement produced by the different construction sequences and pipe materials of two-layer pipe jacking. Nevertheless, the features of the deformation induced by two-layer pipe jacking are not clear, especially in the soil-rock composite stratum. Most of the Jinan area is soil-rock combination strata. Under the environment of accelerated urban development, more and more urban underground pipelines are arranged in the vertical double-layer layout, which means that the properties of the soil layer through which the upper layer and the lower layer are more different. With the rapid development of engineering construction, there is a serious lack of relevant research. Therefore, the study on soil deformation law of vertical double-layer pipe jacking construction in soil-rock combination stratum can effectively fill the research gap in this field, and it does not provide reference for subsequent related engineering and research. Based on a real jacking project of a high-voltage power pipe corridor in Jinan city, on-site monitoring has been designed and carried out, and a large number of data of ground settlement and inner lateral displacement was obtained. Using Midas GTS NX 2021 finite element software, three-dimensional numerical simulation has been done to analyze the deformation of the soil-rock composite stratum. By comparison analysis, deformation features have been discussed and some useful conclusions are obtained. According to a new proposed theoretical model of the buried depth in rock formations of the pipe, the Peck formula has been studied and revised for calculating the ground settlement curve on the soil-rock composite stratum. By the calculation results comparison analysis of numerical and formula methods, the applicability of the revised Peck formula has been proved and can be used for the preliminary estimation of the ground settlement. Thisproject is a vertical double-layer large-diameter pipe jacking construction of soil and rock combination stratum. The upper pipe jacking is located in the soil layer, and the lower pipe jacking is mostly located in the rock layer. The construction site is small, the scope of the construction influence is difficult to determine, and there is a lack of relevant engineering monitoring scheme for reference. Therefore, the layout and protection of site monitoring and measuring points are a great test for experimental research. In addition, during the derivation of the formula, the factors that caused the difference between the peck formula and the surface settlement caused by pipe jacking in the soil-rock combination stratum are not clear, which is a great challenge for the correction of the peck formula.