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Based on the overlapping tunnel of Tel Aviv Red Line Light Rail Project in Israel, this study established a three-dimensional numerical model by using Rhino6 and FLAC3D software on the basis of analysis of on-site monitoring data, to investigate the ground settlement and stratum displacement laws of shield overlapping tunnel at different overlapping angles.Results show that when the two tunnels gradually transit from horizontal to overlapping state, with the increase of overlapping angle of the two tunnels, the accumulated settlement at the measuring points in the middle of the two tunnels increases, but the accumulated settlement is not only affected by overlapping angle, but also closely related to the stratum traversing situation.Under the stratum condition of the project, when the overlapping angle is 60°, the accumulated surface settlement reaches the maximum because both tunnels pass through the loose reservoir K1 stratum.When the overlapping angle of the rear-built tunnel is less than 45° after excavation, the width of the settlement trough increases.When the overlapping angle is larger than 45° and smaller than 60°, the width of the settlement trough remains unchanged.The width of settlement trough decreases when the overlapping angle is larger than 60°.When the overlapping angle reaches 90°, the settlement trough is symmetrical on both sides.After excavation of tunnels on both sides, when the overlapping angle of the tunnels reaches 75°, the strata on both sides change the direction of movement.This research offer reference for the design and construction of overlapping tunnels.

With the development of informatization and digitalization, the transformation of intelligent manufacturing has become the focus. This paper builds an evaluation system based on the scientific evaluation method of the development level of smart manufacturing and the real demand situation. It establishes an evaluation model of intelligent manufacturing MES systems by combining the GA-BP algorithm. Then, a SeqGAN generative adversarial network is used to expand the real samples. The evaluation model was trained and validated by constructing a training model through the BP neural network, taking the sample data of evaluation indexes as the network input and the seven labels from Industry 1.0 to Industry 4.0 as the network output. The results show that the classification accuracy of the model is above 98%, and all of them have achieved good results. In the actual case evaluation, it is judged that the intelligent manufacturing MES system of Company Z is in the range of industry 3.0 to 3.5, and this result is very close to the manual evaluation of the factory field survey. The synthesis shows that the model is reasonable and effective and has important guiding significance for the evaluation of enterprise intelligent manufacturing MES systems.

TBM hob wear is an important factor that affects the TBM tunneling efficiency and construction cost.Different blade types differ in rock breaking efficiency and wear.By analyzing the rock-breaking mechanism of the arc blade wedged hob, this study established the calculation model of hob normal cutting, and analyzed the influence of hob edge angle on normal cutting force.This study then designed three kinds of hobs with different cutter spacing and three types of hobs with different blade for rock breaking tests in laboratory.Results show that the reasonable cutter spacing is 15mm, sharp blade is prone to be worn, the tooth-like blade, which has higher rock breaking efficiency and wear resistance, is better than arc blade.Combined with the actual situation of the project site, a new hob with wedge-shaped blade is developed, which are applied to inclined shaft TBM tunneling at engineering site.Results show that the wear rate of the new wedge-shaped hob is 20 % less than that of the conventional ones, and the service life of former is longer than that of latter.Under the same geological conditions, new wedge-shaped hob can reduce the number of hobs consumption and improve efficiency of tunnelling.The development and application of the new type successfully solved the problems of hob wear and frequent replacement of hobs in the TBM inclined shaft excavation.It can provide technical support for TBM long distance inclined shaft driving, which not only shortened the construction period, but also saved the construction cost.

The floating of the shield segment will cause the segment to be misaligned and damaged, reducing the overall structural strength, waterproof performance and service life of the tunnel. On the basis of establishing the force model of the segments, by analyzing the force state of the segments, a theoretical calculation model of the segments floating is established. Taking the shield tunneling section ventilation shaft No.3-Caoqiao Station of Beijing Metro's New Airport Line as the engineering background, the abnormal rise of the segment was analyzed. By improving the performance of the synchronous grouting slurry, the floating amount of the tube segment was effectively controlled. And the slurry characteristics before and after the improvement were tested. Finally, based on the results of the slurry test and the theoretical calculation model, the floating volume of the tube segment was calculated. The results show that the theoretical calculation result of segment floating volume is consistent with the actual measured value. The theoretical calculation model in this paper has good accuracy. The segments float up a lot in a short time after it is released from the shield tail. Shortening the setting time of the slurry and improving its early strength are effective measures to control the floatation of the segments.

The aging of rubber will cause changes in the mechanical properties of materials, which in turn will cause waterproof failure.The section from the starting point of Beijing Metro Line 6 to Jin'anqiao is the first fabricated surface excavated tunnel in our country.It is of great significance to study the aging performance of the gaskets at the joints.The tunnel uses segments as the secondary lining structure, and EPDM gaskets as the waterproof material at the segment joints.In order to check whether the waterproof of the joints meets the durability requirements, an accelerated aging test was carried out on the rubber material of the gasket according to time-temperature equivalence principle, which predicts the service life of the rubber material.Due to the cumbersome calculation process of life prediction, the corresponding program was compiled to solve the problem of repeated trial calculation of parameters in the data processing.In addition, a numerical simulation of the stress of segment gaskets was carried out, and the influence of aging on the waterproof of the gasket was analyzed.It was pointed out that the designed water pressure of the gasket was increased to at least 1.75 times of the original one.

Based on the modified Loganathan theory, the longitudinal displacement of an existing tunnel caused by the ground loss in the process of shield crossing was studied. Timoshenko beam theory considering shear deformation was used to analyze the change of tunnel internal force and the amount of the dislocation between the adjacent rings. Based on the shear effect in elastic mechanics theory, the differential equation of tunnel longitudinal deformation was established and solved. After the bending deformation of Timoshenko beam, the difference between the beam cross-section of euler-Bernoulli beam which was not perpendicular to the neutral axis was analyzed. Furthermore, the variation of tunnel bending moment, shear force, and displacement between tunnel segments on tunnel shear stiffness and the ground loss ratio was studied. The results showed that the theoretical solution considering the shear deformation of the tunnel could predict the longitudinal deformation of the tunnel accurately. The proposed theory can correct the excessive internal forces such as bending moment and shear force without considering shear deformation and make up for the defect of unable to calculate the dislocation between the adjacent ring misalignment without considering shear deformation. The research results provide an effective method for predicting the influence of shield on existing tunnels.

Geotextile offers numerous benefits in improving pavement performance, including drainage, barrier functionality, filtration, and reinforcement. Wicking geotextile, a novel variant in this category, possesses the intrinsic ability to drain water autonomously from soils. This paper details the development and application of a comprehensive multiphysics model that simulates the performance of wicking geotextile within a pavement system under freezing climates. The model considers the inputs of various environmental dynamics, including the impact of meteorological factors, groundwater levels, ground heat, and drainage on the pavement system. The model was firstly validated using field data from a long-term pavement performance (LTPP) road section in the cold region. It was subsequently applied to assess the impacts of wicking geotextile if it was installed on the road section. The model simulated the coupled temporal and spatial variations in soil moisture content and temperature. The simulation results demonstrated that wicking geotextile would create a suction zone around its installation location to draw water from surrounding soils, therefore reducing the overall unfrozen water content in the pavement. The results also showed that the installation of wicking geotextile would delay the initiation of frost heave and reduce its magnitude in cold region pavement. [ABSTRACT FROM AUTHOR]

For the complex problem of severe tool wear encountered by shield machines tunneling in full-section hard rock, the relationship between disc cutter installation radius, stratigraphic parameters, tunneling distance, and cutter wear was analyzed by multiple regression analysis, take into account the example of shield project from Chaoyanglu Station to Emeishanlu Station of Qingdao Subway Line 6. Considered various variables such as shield thrust, rotation speed, cutterhead torque, advance speed, installation radius of cutters, UCS and CAI of rock, a face cutter wear prediction model was established to analyze the cutter's wear characteristics, and the following conclusions were drawn: (1) Within the 800 m tunneling distance, the average number of cutter changed per position was 3. 18, and as the installation radius of hob increased. (2) the average wear per linear meter of the cutter increases power exponentially with the increase of rock strength and exponentially with the increase of abrasiveness index, and the fitted correlations coefficient were high, which indicates that the above parameters play a crucial role in cutter wear. (3) the cutter wear calculation model takes into account the tunneling parameters, rock strength and abrasiveness of the rock, can predict the wear pattern of the face cutters of shields in hard rock. In addition, the accuracy of the cutter wear prediction model was verified, and the error between the predicted and measured values do not exceed 13%. [ABSTRACT FROM AUTHOR]

Background: Cleidocranial dysplasia (CCD) is a dominantly inherited disease characterized by hypoplastic or absent clavicles, large fontanels, dental dysplasia, and delayed skeletal development. The purpose of this study is to investigate the genetic basis of Chinese family with CCD. Methods: Here, a large Chinese family with CCD and hyperplastic nails was recruited. The clinical features displayed a significant intrafamilial variation. We sequenced the coding region of the RUNX2 gene for the mutation and phenotype analysis. Results: The family carries a c. T407C (p.L136P) mutation in the DNA- and CBF beta-binding Runt domain of RUNX2. Based on the crystal structure, we predict this novel missense mutation is likely to disrupt DNA binding by RUNX2, and at least locally affect the Runt domain structure. Conclusion: A novel missense mutation was identified in a large Chinese family with CCD with hyperplastic nails. This report further extends the mutation spectrum and clinical features of CCD. The identification of this mutation will facilitate prenatal diagnosis and preimplantation genetic diagnosis.

The Forkhead Box O (FOXO) gene plays a key role in various biological processes, such as growth, metabolism, development, immunity and longevity. Molting is an essential process for crustacean growth, which is mainly regulated by 20-hydroxyecdysone (20E) and molt-inhibiting hormone (MIH). Although the role of FOXO in regulating the immune response of crustaceans is well documented, its involvement in controlling crustacean molting remains unclear. In this study, a FOXO-like gene (designed as EsFOXO-like) was identified in Eriocheir sinensis, and the regulation of the 20E pathway by EsFOXO-like was also investigated. The coding sequence of EsFOXO-like was 852 bp, which consisted of 283 amino acids including a conserved Forkhead (FH) domain. EsFOXO-like shared high similarity with FOXO genes from other crustaceans, and the mRNA expression levels of the EsFOXO-like gene were highest in the hepatopancreas and lowest in the hemocytes. However, transcription and protein expression of the EsFOXO-like gene were found to be up-regulated only during the pre-molt stage in the hepatopancreas, with lower expression levels observed at the post-molt stage. To explore the role of EsFOXO-like in the 20E pathway, EsFOXO-like was firstly inhibited by a specific FOXO inhibitor (AS1842856) and then through an EsFOXO-like dsRNA injection, respectively, and the results showed that the relative expression levels of EsFOXO-like were notably decreased in the hepatopancreas after both the inhibitor and dsRNA treatments. The 20E concentration, the mRNA expression levels of the 20E receptors including the ecdysone receptor (EcR) and the retinoid-X receptor (RXR) and EsmTOR transcription in the AS1842856 group or the EsFOXO-RNAi group were all significantly higher than that in the control group, while the mRNA expression level of EsMIH was significantly decreased after EsFOXO-like inhibition. To further investigate whether the EsFOXO-like acts through mTOR or not, Rapamycin was administered to inhibit mTOR activity in EsFOXO-like inhibited crabs. The results revealed a significant reduction in the concentration of 20E and the expression level of EsMIH in the AS1842856 + Rapamycin group compared to the AS1842856 + DMSO group, accompanied by an increase in EsEcR and EsRXR expression. These findings collectively suggest that EsFOXO-like regulates the 20E pathway through mTOR, which offered valuable insights into the understanding of the molting process in crustaceans. [ABSTRACT FROM AUTHOR]

The construction of overlapping shield tunnels causes secondary disturbance to the ground, which will increase surface deformation. In order to study the law of surface deformation, this paper, relying on the Tianjin Metro Line 5 West Hotel Road-West Huanhu Road Interval and Line 6 West Huanhu Road-West Hotel Road Interval tunnel project, uses FLAC3D to numerically simulate the two excavation sequences and analyzes the measured data of 15 surface monitoring cross-sections to obtain the law of surface deformation of Tianjin soft soil layer overlapping shield tunnel construction. Research results indicate: (1) For the upper tunnel of this project, the reasonable range of advancing earth pressure to static earth pressure ratio α is 2.0~2.4, and the lower tunnel α should be 1. 2~1.6; (2) By fitting the measured surface data, it can be approximated that the settlement parameter k in the Peck formula obeys the distribution of N ~ (0.981, 0.230); (3) The shape and width of the surface settlement curve do not change with different excavation sequences, and the maximum surface settlement of excavation sequence 2 is increased by 0.8 mm; (4) With "first down, then up" excavation sequence, the width of the surface settlement trough is mainly affected by the lower tunnel. [ABSTRACT FROM AUTHOR]