How can you design a deep excavation support system using geotechnical software and modeling?

Before choosing, you need to ask yourself the question if are qualified to handle the design risks associated with deep excavation design. After answering yes, you need to ask if you understand the design principles. With DeepEX from @Deep Excavation LLC, you can design all structural and geotechnical components. From limit-equilibrium to winkler springs, to 2D and 3D FEM, structural design, load combinations, soil property estimations, and bracing design, DeepEX has it all. There is nothing else that comes close. We even caught a Plaxis model that converged just fine but DeepEX with +200 checks clearly shows it collapses. Your last consideration is what kind of expert support you will get. This leaves one clear choice, DeepEX

The geotechnical software should be specific for the problem being investigated. Software capabilities, costs and learning time should all be considered when selecting a software. It is also important to adapt this selection or the level of the analysis to the level of design undertaken (i.e. detailed design will need more advanced analysis than reference designs). Last but not least, the validation of the analysis should use some empirical or closed form equations and not only another software, this allow for a true sanity check of the software calculations.

A variety of methods and instruments, such as geotechnical modelling and software are utilised to build a deep excavation support system. The design and optimisation of deep excavation models is made possible by geotechnical software such as DeepEX, which permits both structural and geotechnical study of the support system. To simulate diverse excavation systems, the software provides a variety of support kinds. Finite element analysis (FEA) is another tool that geotechnical software can use to evaluate the stability of the excavation wall and the stresses it will face. These tools ease the analysis of intricate geotechnical situations, taking into account site-specific elements, and coming up with wise design choices.

1. Site Investigation: 2. Define Excavation Geometry: 3. Soil Analysis 4. Groundwater Analysis: 5. Load and Structural Analysis: 6. Select Support System: 7. Stability Analysis: 8. Optimization: - Iteratively adjust the design parameters to optimize the support system for safety and cost 9. Documentation: 10. Construction Monitoring: - Implement a monitoring plan during construction to observe the actual performance of the excavation support system. - Compare observed behavior with the predicted behavior from the design. Utilizing specialized geotechnical software, such as Plaxis, GeoStudio, or FLAC, can streamline these processes and provide more accurate and efficient results.

Not the first thing - the first thing to consider is whether you understand the local topography (how long - how high), next is the in service loads (earth pressures, ground water, surcharges etc), next ground conditions (both passive and active), then Client / stakeholder preferences in terms of build ability (driven piles acceptable? Tall installation equipment?), next temporary works arrangements (cut slopes, working platforms, flood protection etc). With all that to hand you can start to think about the software for modelling it with…

- Only, the relevant codes and standards to be adapted, as some of them are aligned with different geographical natures and areas. - The other imported data must have a reasonable/ high level of accuracy. - The Survey Reports to be reviewed by a professional, prior proceeding to the next stage (it's easier to amend mistakes now than later).

In my experience, To input these parameters into the geotechnical software, you can opt for manual entry or import data from diverse sources, including field tests, surveys, or maps. Furthermore, it is advisable to establish the units, coordinate systems, and scales that will be utilized throughout the project to ensure consistency and accuracy in the analysis and design processes. This meticulous definition of project parameters lays a solid foundation for the subsequent stages of the deep excavation project.

The choice of geotechnical software depends on the type of environment and its material in terms of soil or rock and in terms of joints. I usually use RS2 ,Flac, and Plexis

Accurate project parameters are crucial. Define soil properties, groundwater levels, and structural details. Input precise information about adjacent structures, as well as any constraints or limitations. A comprehensive understanding of project-specific conditions lays the foundation for a reliable support system design.

The most important thing is depth of excavation versus area available to excavate around, type of machinery that can be moved, its surcharge, man material movement, supporting framework lead time, availibility, constructability, in short feasibility of man, material, machinery, time and characters of excavation technical and cost. If the considered area has been properly studied for geotechnical parameters and what about surrounding live load and surcharges ? Everything cannot be considered by software. I feel the task has many other important challenges than just using a software. As stated by other contributors, the engineering mathematical parameters are equally required for correct analysis by so called software.

Selecting an appropriate support system is crucial, factoring in both site conditions and the depth of excavation. The available options such as driven piles and diaphragm walls, secant piles, jet grouting, or soil nailing necessitate a thorough evaluation. With my extensive experience, I employ a meticulous approach to assess and select the optimal support system that best aligns with the project's unique requirements. Ensuring safety and stability, I emphasize compatibility between the chosen system and the geotechnical software's analysis capabilities. This synergy allows for a comprehensive and precise evaluation of the selected support system, ensuring its efficacy in meeting the project's safety and structural objectives.

One invaluable insight I've gained is the significance of meticulously selecting a support system type when designing a deep excavation through geotechnical software and modeling. This crucial third step involves identifying a support system that not only aligns with the specific needs of the project but also accommodates any inherent constraints. A support system encompasses elements like retaining walls, anchors, struts, braces, collectively working to provide stability and resistance to the excavation's depth. The geotechnical software facilitates the exploration of various support system types, including soldier pile and lagging, sheet pile, secant pile, diaphragm wall, slurry wall, soil nail, or jet grout.

To select the support system, one should pay attention to the implementation conditions, availability at the project site, and optimality from the technical and economic point of view

Choose the appropriate support system based on excavation depth, soil type, and adjacent structures. Options include soldier piles with lagging, secant or tangent pile walls, or diaphragm walls. Consider the balance between structural integrity and constructability, aligning the choice with project-specific needs.

As the soil engineering is quite tricky, it may involve al together different framing system than conventionally the software may handle. IN such case soil structure interaction experts are greatly recommended as they can use softwares like ansys, and other FEA softwares with variety of input and behaviour controls with equivalent soil structure modelling and its interaction with support system and properly addressing construction loads, active and passive soil interactions and surrounding surcharges and environmental parameters, etc.

This meticulous design phase is essential for achieving a support system that not only meets safety standards but also efficiently addresses the unique challenges posed by the specific characteristics of the deep excavation project.

At this stage, geotechnical software helps you to design the most optimal support system, which shows that you have an engineering perspective on the project or are just a user to use the software.

Detail the design of support system components, including pile dimensions, spacing, and reinforcement. Geotechnical software facilitates the application of design codes and standards, ensuring structural stability under various loading conditions. Iteratively refine the design to optimize performance.

once the software is able to model the support system, the field experts need to first go through the solution as worker and machinery movement is best understood by them. Without conisdering the working and machine clearances, the great solution by software could be useless- unexecutable. Point to be noted here that all geotechnical experts or software tool experts may not be well versed with construction technology and structural engineering or behaviour. So a team of appropriate experts has to continuously evolve the solution not just software.

Utilizing the selected software, with extensive experience allow to meticulously craft the support system's components. This process involves precise modeling of geometry, material properties, and installation sequences. Employing advanced features within the software, enable to determine the necessary dimensions, depths, and spacings of critical elements such as piles, anchors, or retaining walls. the proficiency of the designer ensures a comprehensive and accurate design, emphasizing structural integrity, stability, and adherence to project specifications. This detailed approach, combining software capabilities with my expertise, results in a robust and meticulously planned support system, essential for successful deep excavation projects

During my tenure, I have found this simulation step invaluable in foreseeing potential challenges, optimizing construction sequences, and ensuring that the designed support system maintains stability throughout the entire construction process. The ability to simulate construction stages not only enhances the accuracy of the design but also provides a platform for proactive decision-making, enabling engineers to address and mitigate potential issues before they arise on the field. This forward-looking approach, facilitated by geotechnical software, significantly contributes to the overall success and safety of deep excavation projects.

Utilizing the geotechnical software, allow to execute a methodical approach in implementing sequential construction stages. By drawing on simulating each stage meticulously, encompassing excavation, support system element installation, and soil removal processes. Employing the software's advanced simulation capabilities, enables conduct a comprehensive analysis of the impacts caused by these stages. This includes a detailed examination of soil displacement, deformation patterns, and stress distribution. The in-depth understanding of the interplay between construction activities and ground behavior, facilitate informed decision-making and optimizing the design for stability, safety, and efficiency throughout the project's lifecycle.

All parameters and scenarios must be initially covered and listed before attempting design. At this stage all the possible worst scenarious must be evaluated and reviewed by all concerned expertise.

Geotechnical software allows you to simulate excavation stages to assess the system's response over time. Model construction sequences, considering excavation, support system installation, and subsequent phases. Analyse the impact of each stage on soil-structure interaction, enabling proactive adjustments to enhance performance.

in my experience i wont use a single software for all the design procedure as the soil and strut structure would need their own specific software for simulation purpose. one practical way to model and excavation would be modeling the soil excavation and strut in PLAXIS2D or 3D and after the Analyse is done write down the moments & forces generated and apply them to the strut model which should be rebuild in SAP2000

Perform additional checks to confirm the stability of the chosen support system. This may include load calculations and stability analyses for different loading conditions. Document the results of your design in a detailed technical report. Provide clear recommendations on the implementation of the support system.

Utilize the visualization tools in the chosen software to comprehend the dynamic behaviour of the excavation support system. Analyse factors such as deformation, stress distribution, and groundwater flow. This visualization aids in identifying potential issues and refining the design for optimal performance.

A visualiza??o e análise de resultados é crucial. O espírito crítico na análise e o manipular saudável de dados para a otimiza??o da solu??o s?o pontos chave para o processo.

Unfortunately, none of the advice given so far in this discussion topic actually relates to design. Design is the process of choosing the correct geometry, ground model, ground parameters, ground retention system, support system, sequence of construction and materials for the ground retention/support. Good advice above on how to model and analyse the problem, but software does not design, it only allows the Designer to calculate and analyse. Once you have a range of analysis outputs, then the design process can begin. In this case, the design has to cater for the bending moments and shear forces in the ground retention element [say sheet or bored piles], axial forces and potential bending moment in the support system [say props or anchors].

On the other side of technical approach,occasionally soil behaviors can not be predictable. Here is some simple guidance what else to consider -Let all shareholders consider the worst scenario. -Listen the community of place. They may know some oldest stories such as; some older landslides ,some overflowing and etc. -Social and environmental factor of place such as; sometimes an old tree can be more important then new road or sometimes a grey slope stabilization done with shotcrete can be ugly in forested place.

Beyond the technical aspects, consider the importance of collaboration among multidisciplinary teams. Engage with geotechnical engineers, structural designers, and construction professionals to benefit from diverse expertise. Regularly update your knowledge on the latest advancements in geotechnical software and construction methodologies to ensure your designs align with industry best practices.

most important is to track the performance of your model to what the instruments are saying. followed by updating and recalibrating your model.

Other things to be considered apart from softwares, type of structures, excavation sequence, and support system, the good quality of soil data including drain and undrained parameter should be considered. The existing condition of excavated area shall consider surrounding condition, including existing upper structure and underground condition. This will affect the lateral earth pressure to the supporting structure. The good quality of soil data interpretation will affect to the determination of k0, ka, or kp of soil, buoyancy, seepage, and other UG consideration.