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It is important for shield tunneling safety to predict and control the instantaneous surface settlement. Particularly, the complex geological condition can make accurate prediction more difficult. To adapt to the stratum distribution, a semi-analytical method is established by introducing the finite layer method into tunnel mechanical analysis. Firstly, based on the elastic solution of the finite layer method, the horizontal flexibility coefficient of tunneling and the surface settlement are obtained by applying effective thrust to the excavation face. Secondly, two influencing factors are analyzed, including the penetration of shield tunneling and the Poisson ratio of geotechnical parameter. The relationship formula between the measured value and the theoretical value of the maximum settlement is derived through data fitting. Finally, the settlement prediction method of tunneling is proved to be practical, which provide a new ideal for the mechanical analysis of tunnels in composite strata.

It is important for shield tunnelling safety to predict and control the instantaneous surface settlement. Particularly, the complex geological condition can make accurate prediction more difficult. To adapt to the stratum distribution, a semi-analytical method is established by introducing the finite layer method into tunnel mechanical analysis. Firstly, based on the elastic solution of the finite layer method, the horizontal flexibility coefficient of tunnelling and the surface settlement are obtained by applying effective thrust to the excavation face. Secondly, two influencing factors are analyzed, including the penetration of shield tunnelling and the Poisson ratio of geotechnical parameter. The relationship formula between the measured value and the theoretical value of the maximum settlement is derived through data fitting. Finally, the settlement prediction method of tunnelling is proved to be practical, which provide a new ideal for the mechanical analysis of tunnels in composite strata.

The rapid development of data science promotes the innovative application of data mining algorithms in geotechnical engineering. So the multidimensional association algorithm is tried in the technical optimization of shield tunneling. Based the original data sets on geological condition, tunneling operation and monitoring, the data preprocessing is carried out according to such steps as sorting and statistics, classification and coding, factor selection and data discretization. Then eight important parameters are selected for association analysis, including tunneling layer, surface settlement, and six operating parameters of the shield machine. Apriori algorithm is used for mining the association rules to establish the association models of those parameters, whose rationality is tested. Also the engineering significance of the multi-parameter association models is explained in the view of practical experience. Finally, the data mining principles of the shield tunneling parameters association rules are discussed. As a simple and reasonable data analysis method, the association algorithm provides a new way for the intelligent construction of shield tunneling.

In2O3, MnO/In2O3, and MgO/In2O3 catalysts are synthesized by the co-precipitation method and investigated for CO2 hydrogenation to methanol. The introduction of Mn and Mg oxides dramatically enhances the CO2 adsorption capacity of In2O3. The changing trend of methanol selectivity is consistent with the CO2 adsorption capacity. MnO/In2O3 and MgO/In2O3 catalysts show higher methanol selectivity compared with that of In2O3.

The layered nature of natural soil must be considered in ground engineering. To this end, a ground finite layer method (FLM) based on extended patterns is proposed on the basis of the principles of traditional FLM. First, the displacement mode of the layer element uses the multiplication form of a quintic fully polynomial and double series. By superposing the calculated solutions of four symmetric loading patterns, the extended FLM can be used to analyze the mechanical state of ground under various types of loads. Second, the selection principles and methods for some important parameters of the extended FLM are established by analyzing and discussing the stress and displacement characteristics of ground loaded with vertical unit force. Finally, after a comparison with the solutions of classical analytical methods, such as the Boussinesq, Mindlin, and Cerruti formulae, the extended FLM is verified to be rational and accurate outside of the loading influence range. Thus, the proposed method will be easier to use in practice due to its adaptability to layered ground; however, its scope of influence and its mechanism near the loading position require further research.