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The recent work of anthropologists, historians, and historical archaeologists has changed the very essence of military history. While once preoccupied with great battles and the generals who commanded the armies and employed the tactics, military history has begun to emphasize the importance of the “common man” for interpreting events. As a result, military historians have begun to see military forces and the people serving in them from different perspectives.

This book compiles a series of case studies derived from archaeological excavation in Greek cultural contexts in the Mediterranean (ca. 800-100 B.C), addressing the current state of the field, the goals and direction of Greek archaeology, and its place in archaeological thought and practice. Overviews of archaeological sites and analyses of assemblages and contexts explore how new forms of data; methods of data recovery and analysis; and sampling strategies have affected the discourse in classical archaeology and the range of research questions and strategies at our disposal. Recent excavations and field practices are steering the way that we approach Greek cultural landscapes and form broader theoretical perspectives, while generating new research questions and interpretive frameworks that in turn affect how we sample sites, collect and study material remains, and ultimately construct the archaeological record. The book confronts the implications of an integrated dialogue between realms of data and interpretive methodologies, addressing how reengagement with the site, assemblage, or artifact, from the excavation context can structure the way that we link archaeological and systemic contexts in classical archaeology.

Traditional rectangular tunnel boring machines have low tunneling efficiency, poor soil mixing effects, which has hindered the construction of long-distance and large-section box jacking projects. To overcome these limitations, a new type of full-face excavation boring machine was developed based on a planetary transmission mechanism. This machine achieves full-face excavation by utilizing three eccentric cutter heads that revolve around both the central axis of the cutter plate and their individual shafts. The design methodology, feasibility, and principles of this new mechanism were introduced. Furthermore, a successful construction project of an underground highway passage in Japan was presented as a case study to demonstrate the design and application of this tunnel boring machine. The case details include the excavation face support mechanism, optimal cutter-head layout, obstacle removal strategies, and methods for reducing jacking resistance. Monitoring data from the project verified the applicability, reliability, and overall engineering performance of the rectangular shield machine developed using the planetary mechanism. This research demonstrates that the planetary transmission mechanism-based boring machine offers superior performance in terms of ground settlement and tunneling speed, potentially providing a comprehensive solution to the challenges in the development of rectangular shield machines for box jacking projects.

This paper reports a typical case history of deep braced excavation for constructing the main bridge cushion cap of the Yangwan River Bridge to explore the excavation performance under embankment surcharge load. Three-dimensional finite difference analysis, simulating the whole construction process of this case history, was performed to capture the effects of the embankment–excavation distance, revel level, and excavation bottom sealing on the responses of the earth retaining structure and the ground. It was found that both the ground surface settlement and the retaining structure deformation are larger on the near-embankment side than the far-embankment side. The responses on the near-embankment side are more sensitive to the embankment–excavation distance and the river level. However, the effects of these parameters diminish greatly when the embankment–excavation distance exceeds 1.5 times the excavation depth. The excavation bottom sealing measures can reduce the retaining structure deformation, and effectively restrain basal heave. This restraint weakens as the excavation bottom sealing thickness exceeds 1 m.

This paper focuses on a deep foundation pit project of a metro shaft constructed by the cover-and-excavation reverse method in a section of Guangzhou Metro Line 13. This study integrates field monitoring data, three-dimensional finite element simulations, and parametric analyses to propose a systematic optimization design framework, providing a more comprehensive and reliable quantitative basis for the design of support structures for deep metro foundation pits constructed using the cut-and-cover top-down method. The study examines the effects of pile diameter, pile spacing, embedment depth, and types of retaining structures on pit deformation. The results indicate that increasing the pile diameter from 800 mm to 1000 mm reduces the maximum lateral displacement of the retaining structure by 30.7%, while decreasing the pile spacing from 2000 mm to 1600 mm results in a 17.5% reduction in deformation. However, beyond these thresholds, the marginal improvement becomes less significant. An embedment depth of 4 m for shallow sections and 2.5 m for deep sections is recommended to balance deformation control and construction economy. Diaphragm walls outperform bored piles and secant piles in deformation control. The optimized design achieves an estimated cost reduction of approximately 15% while maintaining safety requirements. The optimized parameters and comparative conclusions derived from this study can be directly applied to the design of deep foundation pits for metro stations under similar geological conditions. These findings provide crucial data support and theoretical reference for formulating more economical and safer design codes and standards.

In response to increasingly stringent safety and construction environmental impact requirements for urban underground engineering, this study investigates the performance of a steel strut servo system braced deep excavation adjacent to existing buildings, using a subway station project as a case study. A three-dimensional finite element model is established to analyze the behavior of the steel strut servo system during deep excavation, focusing on the deformation characteristics of soil and structural members, as well as the factors influencing the system’s performance. The findings indicate a strong correlation between the deformation of soil and structural members and the excavation depth, with greater deformation observed at deeper depths. When excavation is completed, the maximum and minimum vertical displacement of soil mass are 24.3 and − 5.8 mm, respectively. The maximum total displacement of buildings A and B is 3.86 and 3.82 mm, respectively. The servo system can inhibit the displacement of diaphragm wall to some extent. The maximum values of the servo area and other areas are 25.21 and 40.4 mm, respectively. The axial force of the strut is mainly pressure, with a maximum value of − 2,883.4 kN. The horizontal displacement of diaphragm wall is sensitive to the change of servo system position and servo axial force value. The deformation control effect is best when all steel struts are controlled by servo system. When the servo system is set with 2 struts, the maximum value decreases as the position of the servo system moves down. In addition, the maximum displacement decreases with the increase of the servo axis force value. This research provides valuable insights for the design optimization and construction control of similar projects.

With the increase of urban development in big cities, the requirement for deep excavations to build the tall building foundations of has increased significantly. Depending on the dimension and location, these excavations can have an important effect on underground tunnels, especially subway tunnels. In order to get a better realization of the behavior of an existing tunnel due to a vicinity deep excavation, this research that consists of three main parts, propose new intelligent models for predicting the excavation-tunnel displacements using machine learning. For the purpose four equations present to predict displacements of the excavation-tunnel complex. In the first step, a three-dimensional (3D) finite-element (FE) model validate against case stories. In the second step, a number of three-hundred and sixty 3D simulations of an existing tunnel located directly beneath an excavation under different parameters such as excavation geometry and tunnel positions beneath the excavation were carried out. Finally in the third part, based on the simulation results two models developed for predict and validate the , , and values. Based on 3D FE results, the displacements mechanisms of the excavation-tunnel complex were presented. It was observed that the ratio variation have a more effect on the values than . Additionally, the values occurs approximately in the middle . The results demonstrate that when the tunnel located at very close beneath the excavation area, tunnel tends to move vertically towards the excavation area. As value increases, the vertical displacement values of the tunnel decrease. The proposed models validated against FE results the results show that the models has an acceptable performance in estimating the of excavation and tunnel displacements.

In situ investigations and detailed laboratory tests indicated that the granite at the Laxiwa hydraulic station is a typical hard rock, with high compressive strength and elasto-brittle failure modes, such as spalling and slabbing, and that the underground caverns are prone to brittle failure. Thus, an intelligent optimization method for cavern excavation was developed to improve the underground engineering’s stability during its construction. This artificial intelligence method utilized the advantages of both the particle swarm optimization algorithm, which is capable of global optimization, and the support vector machine algorithm, which is capable of highly nonlinear mapping. The corresponding numerical analysis indicated that this optimization of excavation sequencing can considerably reduce both the total volume of the damage zone and the brittle failure of the surrounding rock. Furthermore, the measured deformations, the depth of the tested excavation damage zone, and the exposed in situ failures resulting from the applied excavation scheme were similar to the results predicted by the numerical simulation of the cavern excavation.

This research aims to comprehensively study the deformation characteristics of an excavation pit of 7,600 m 2 (117 m long, 65 m wide and 20.8 m deep) in soft clay in Shanghai, China. The deformation characteristics of the mixing pile in both the vertical and lateral directions, ground surface movement, and surface displacement in the adjacent tunnels were comprehensively investigated. The results indicated that the maximum lateral deflection was approximately 85 mm at the end of the excavation and that the maximum lateral displacement, δ hm , was in the range between 0.12% H e and 0.41% H e . The factor of safety of the excavation was approximately 1.6, which was larger than that of most reported sites in Shanghai. The relationship between heaving and excavation depth was strong between 0.0047% H e and 0.056% H e , and a relatively large settlement was observed at a distance of approximately 0.2H e – 0.3H e . The tunnel surface of the eastbound line deformed upward and inward with a maximum horizontal convergence of 4 mm. A multilayer regression model was also validated, showing a maximum discrepancy of 26.5 mm. This research provides a valuable historical case for the documentation of the deformation characteristics of excavation pits close to existing foundation pits and tunnels.

This study investigates the behavior of retaining structures and the settlement of external surfaces in deep foundation pits located in areas characterized by muddy soft soil. The research evaluates the efficacy of two constitutive models—the traditional Mohr-Coulomb model and the modified Cambridge model—during the simulation of foundation pit excavation. By analyzing actual monitoring data collected from the site, the study identifies patterns in the settlement and deformation of both the retaining structure and the surface. Subsequently, the excavation process of the foundation pit is simulated using FLAC3D 6.0 software, employing both the Mohr-Coulomb and modified Cambridge models. A comparative analysis is conducted between the simulation results and the field monitoring data to assess the performance of the two models.The findings indicate that the horizontal displacement and surface settlement curves of the retaining structure in muddy soft soil exhibit cantilever behavior. The maximum horizontal displacement occurs near the excavation face, while the peak surface settlement is observed 15 m from the foundation pit, remaining within the established early warning thresholds. Although both models demonstrate a similar trend in the simulated displacement curves compared to the actual deformation curves, there are notable differences in accuracy. Specifically, the modified Cambridge model generally exhibits a lower error rate in simulating the horizontal displacement of the retaining structure compared to the traditional Mohr-Coulomb model. Furthermore, the modified Cambridge model provides a closer approximation to the measured values for surface settlement outside the foundation pit.In conclusion, for deep foundation pits associated with subway construction that utilize concrete support and underground continuous walls in muddy soft soil regions, the horizontal displacement and surface settlement curves of the retaining structure display cantilever characteristics. The modified Cambridge model demonstrates superior simulation performance, yielding results that are more closely aligned with actual monitoring data.