Geotechnical Engineering Depths: Shallow to Mega-Projects Explained

🌍Background Review Without Purpose? Rethinking the Foundation of Geotechnical Design! In geotechnical engineering, we often inherit site data, instrumentation, and historical reports without clarity on their original intent. A purposeful background review isn’t just a checkbox—it’s the foundation of design integrity. We need to ask ourselves the following: -What investigations shaped this site—and were they short-term or long-term in scope? -What Indigenous knowledge and land use insights are available? -What climate and hydrological data influence risk? -What assumptions are “baked” into previous models—and are they still valid? Many instruments were installed during construction to verify design assumptions—but were never intended for long-term monitoring. Without documentation that distinguishes short-term from long-term intent, we risk misallocating resources and missing critical signals. Instrumentation should never follow a “cake recipe.” It must be embedded intentionally into the Operations and Maintenance Manual (OMS)—the bible of dam safety—reviewed and updated regularly, so it can truly serve as an early warning system for poor performance. At Elevate Civil Engineering Consulting, we use a structured checklist to ensure all relevant data is received for geotechnical projects. We also perform a gap analysis to identify missing information—whether it’s geotechnical site data, instrumentation intent, climate data, or Indigenous land use knowledge—so our designs are built on truth, not assumption. We often find piezometers installed in geotechnically appropriate locations and depths—but their functionality and accuracy are questionable. Dam owners may spend significant portions of their budgets reading instruments that no longer provide reliable data. This not only wastes time and money—it can lead to misleading interpretations and false confidence. A strong background review for a Dam Structure should include: ·        Site history and geological context ·        Instrumentation records and performance trends ·        Regulatory frameworks and design basis ·        Climate data and future scenarios ·        Emergency Response plans ·        Surveillance and Monitoring Plan ·        Operation, Maintenance, and Surveillance Manual As I prepare for #GeoManitoba2025, #CDASaskatoon2025, and #TMW2025, I encourage engineers and clients to reflect: 📘 How intentional is your background review process? 🌍 Are you integrating all available knowledge—including Indigenous and climate data? 🛠️ Is your design basis built on truth—or assumption? If you're interested in the full checklist we use for dam safety reviews and wish to work with Elevate Civil Engineering Consulting reach out! #DamSafety #GeotechnicalEngineering #DesignBasis #BackgroundReview #ClimateResilience #IndigenousKnowledge #Mining #EngineeringLeadership #CDA2025 #GeoManitoba2025 #TMW2025 #CGS #HydrotechnicalEngineering #TwoEyedSeeing #Research #Innovation

GeoInnovative Specialists Inc. (GSI) provides comprehensive Engineering, Pre-Construction, and Geoscience Consultancy Services throughout the Philippines, including: Cone Penetration Testing (CPT) Conventional Geotechnical Investigation & In-Situ Testing Materials Testing Liquefaction and Ground Stability Analyses Structural Analysis and Design Geodetic Surveying Geophysical Testing (ERT, Georesistivity, GPR) Geologic Mapping (including Schmidt Hammer Testing) Hydrologic and Hydraulic Analyses, Flood Assessment, and Drainage Design GAR / EGGAR Environmental Studies GSI is a 100% Filipino-owned corporation, founded by a team of highly skilled specialists with expertise in Geology, Engineering, and their practical applications, including Geotechnics, Geophysics, and Design. Guided by innovation, the company is committed to delivering sustainable, reliable, and cost-efficient solutions across various stages of development for industries such as Infrastructure, Mining, and Energy. Established and duly registered in June 2017, GSI began as a general contractor specializing in Geotechnical Investigation Works—including drilling, test pitting, materials testing, and consultancy. Over the years, the company has expanded its capabilities to serve industrial, private, and public sector projects, with active involvement in feasibility studies and civil engineering works. Operating under its brand GSI, the company upholds its core values of Expertise, Responsibility, Quality, and Teamwork. Its team of professionals is well-trained and experienced in addressing both technical and logistical challenges, ensuring the delivery of expert investigations, sound analyses, and practical recommendations. All implementations and methodologies adhere to international geological and engineering standards, refined through years of proven practice.

Amr Helal, Ph.D., P.E., PMP I couldn't agree more. Let me add the following areas: *Ground Improvement & Soil Stabilization: methods such as compaction, grouting, vibro-replacement, geosynthetics, chemical stabilization, and use of industrial byproducts (slag, fly ash, etc.). *Pavement Geotechnics: subgrade evaluation, soil–pavement interaction, and design of pavement foundations. *Environmental Geotechnics: landfill liners, contaminant migration, remediation, and waste containment systems. *Offshore & Marine Geotechnics: foundations for offshore wind turbines, oil platforms, ports, and coastal structures. *Geotechnical Risk & Monitoring: instrumentation, monitoring ground movements, settlement, and applying probabilistic/risk-based design. *Cold Regions Geotechnics: permafrost, frost heave, and ground freezing solutions.

🚢 Real-World Geotechnical Engineering in Offshore Projects 🌊 I am excited to share one of my works on Spudcan Penetration Analysis for WT-2 at Siri F location in the Persian Gulf. This analysis involved advanced geotechnical assessment using ISO guidelines, empirical and analytical methods (Houlsby & Martin, Meyerhof, Randolph & Gourvenec), and detailed soil–structure interaction evaluation. Such studies are critical for ensuring the safety of jack-up operations, preventing punch-through failure, and optimizing installation planning — all of which directly influence project cost, time, and safety. 🔍 My focus as a geotechnical/offshore engineer has always been to bridge advanced numerical modeling and practical offshore challenges — from free-span correction and pipeline stability to suction pile and spudcan behavior. 📄 You can view the detailed report. #GeotechnicalEngineering #OffshoreEngineering #JackUp #Spudcan #SoilStructureInteraction #OffshoreGeotechnics #NumericalModeling #OffshoreWind #EnergyTransition #EngineeringLeadership

⏳ From Legacy Design to Modern Safety: Rethinking Dam Safety In geotechnical engineering, we often inherit not just instrumentation—but entire design frameworks—without questioning their relevance to today’s risks. Many Canadian dams still operate on 20th century design assumptions, built before climate modeling, Indigenous consultation, or advanced tools like FLAC were available. Are we relying on slope models and safety factors that no longer reflect reality? Design basis should be revisited with intent: -What failure modes are we still assuming? -What new risks (e.g., climate, seismic, societal) are we ignoring? -What modeling tools are we using—and are they validating current conditions? Without this clarity, we risk maintaining systems that are technically sound but strategically outdated. True safety begins with purposeful review: -Modeling that reflects current geotechnical and hydrotechnical data -Design assumptions aligned with modern hazard classifications -Instrumentation that gives accurate and useful information -Accurate geotechnical information with proper depth of coverage and spatially representative data -Accurate and up to date water balance and watershed review When design basis is dated and mining companies choose to decline updating: -They risk false confidence in aging infrastructure -We(ENGINEERS) fail to protect communities from evolving threats. -Together, we created room for Dam failures that threaten society and the environment As engineers, we owe it to our teams, our clients, and our communities to ask better questions about the systems we rely on. Dam Safety starts with intent—and ends with action. As I prepare for #Geomanitoba2025 #CDASaskatoon2025 and #TMW2025 i encourage dam and mining clients, and engineers to ask themselves the following questions. -How old is your design basis—and when was it last reviewed? -Are your slope models validating current risks—or historical assumptions? -How can our community work together to protect society and the environment as we face the onset of climate change and the #actofgodstorms? #DamSafety #EngineeringLeadership #InfrastructureResilience #ClimateAdaption #ClimateChange #TwoEyedSeeing #WaterSecurity #IndigenousKnowledge #Mining #Audits #CDA2025 #TMW2025 #Geomanitoba2025 #CGS #GeotechnicalEngineering #HytrotechnicalEngineering #Research #Innovation #DamSafety #DesignBasis #InstrumentationWithIntent #SlopeStability #FLAC #GeotechnicalEngineering #HydrotechnicalEngineering #ClimateResilience #IndigenousKnowledge #InfrastructureRenewal #EngineeringLeadership #GeoManitoba2025 #CDA2025 #TMW2025 #TwoEyedSeeing #WaterSecurity #Mining #Audits #Research #Innovation #SafetyCulture #EngineeringEthics #ResilientDesign #FiniteElementAnalysis #PolicyAndPractice #CommunitySafety #EthicalEngineering #ClimateAdaptation #SustainableInfrastructure #TechnicalLeadership #InfrastructureDesign #FLACModeling

Geotechnical engineers use analytical reports like the subsurface soil investigation and water table map data to help them decide how to proceed on a construction project, whether it is for building a new school, redeveloping along the highway, or expanding a business. The information they gather allows them to advise architects and developers about potential foundation issues or problems with the soil or water in an area. These specialists help solve problems with existing structures and foundations too. https://lnkd.in/eSqRFSgW #KagaoanEngineering #GeologicalEngineers #GeotechnicalEngineers

Geotechnical Investigation for Slab Settlement A geotechnical investigation was undertaken to evaluate the causes of settlement and failure of the concrete slab, approximately 10 metres from the sea. The slab is 0.5m thick and underlain by 1.0m of backfill material, which has been observed to be porous and weakly compacted. Distress has been recorded in the form of sinking and cracking, necessitating a detailed understanding of subsurface conditions and the proposal of suitable mitigation measures to ensure long-term slab stability. Drilling and Sampling Procedures: The investigation included drilling fifteen boreholes to depths of 15 metres, with two additional boreholes extended to 40 metres for profiling the deeper subsurface. Drilling was executed using rotary techniques to recover both disturbed and representative samples for laboratory testing. Disturbed samples were used for classification and index property analysis, while representative samples enabled determination of soil strength and compressibility. In Situ Testing: To characterize the soils in their natural condition, Standard Penetration Tests (SPT) were carried out at 1.5 metre intervals within the boreholes. SPT provided N-values used to assess relative density, shear strength, and stiffness of the soils encountered. Samples retrieved during SPT were correlated with blow counts to refine soil classification and engineering interpretation. An Electrical Resistivity Tomography (ERT) survey was also undertaken to delineate variability in soil stratigraphy and to highlight groundwater influence beneath the slab. Subsurface Conditions: The stratigraphy is dominated by loose to medium dense sands intercalated with silty and clayey horizons and layers of completely to highly weathered sandstone. Marine sands are prevalent, highly pervious, and directly influenced by tidal fluctuations. The shallow groundwater table enhances washout and erosion of fines. The backfill immediately beneath the slab was particularly porous and uncompacted, creating preferential seepage paths and voids. Problem Diagnosis and Mitigation: Slab failure is attributed to uncontrolled backfill, groundwater ingress, and compressible marine sands. To mitigate, systematic grouting is proposed beneath the slab to depths of about 1.0m. Cementitious grouts will fill voids and seal the porous backfill, while microfine or chemical grouts will permeate finer sandy horizons. Compaction grouting may be applied to densify loose layers, and localized soil replacement with engineered fill can be considered. Improved drainage will further reduce tidal groundwater impact. Should settlement persist, micropiles may be installed to transfer loads to deeper sandstone strata.

Geotechnical Investigation for Slab Settlement A geotechnical investigation was undertaken to evaluate the causes of settlement and failure of the concrete slab, approximately 10 metres from the sea. The slab is 0.5m thick and underlain by 1.0m of backfill material, which has been observed to be porous and weakly compacted. Distress has been recorded in the form of sinking and cracking, necessitating a detailed understanding of subsurface conditions and the proposal of suitable mitigation measures to ensure long-term slab stability. Drilling and Sampling Procedures: The investigation included drilling fifteen boreholes to depths of 15 metres, with two additional boreholes extended to 40 metres for profiling the deeper subsurface. Drilling was executed using rotary techniques to recover both disturbed and representative samples for laboratory testing. Disturbed samples were used for classification and index property analysis, while representative samples enabled determination of soil strength and compressibility. In Situ Testing: To characterize the soils in their natural condition, Standard Penetration Tests (SPT) were carried out at 1.5 metre intervals within the boreholes. SPT provided N-values used to assess relative density, shear strength, and stiffness of the soils encountered. Samples retrieved during SPT were correlated with blow counts to refine soil classification and engineering interpretation. An Electrical Resistivity Tomography (ERT) survey was also undertaken to delineate variability in soil stratigraphy and to highlight groundwater influence beneath the slab. Subsurface Conditions: The stratigraphy is dominated by loose to medium dense sands intercalated with silty and clayey horizons and layers of completely to highly weathered sandstone. Marine sands are prevalent, highly pervious, and directly influenced by tidal fluctuations. The shallow groundwater table enhances washout and erosion of fines. The backfill immediately beneath the slab was particularly porous and uncompacted, creating preferential seepage paths and voids. Problem Diagnosis and Mitigation: Slab failure is attributed to uncontrolled backfill, groundwater ingress, and compressible marine sands. To mitigate, systematic grouting is proposed beneath the slab to depths of about 1.0m. Cementitious grouts will fill voids and seal the porous backfill, while microfine or chemical grouts will permeate finer sandy horizons. Compaction grouting may be applied to densify loose layers, and localized soil replacement with engineered fill can be considered. Improved drainage will further reduce tidal groundwater impact. Should settlement persist, micropiles may be installed to transfer loads to deeper sandstone strata.

In your case (hangar), the slab is not a structural element. Grouting, even with thin grout (W/C = 3/1), will not be effective unless applied under pressure, and applying pressure would risk demolishing the entire slab. Check the cracks within the slab to determine whether they are still active. If they are not, this indicates that the immediate settlement of the poorly placed backfill has already been completed. In that case, you can simply repair the non-structural cracks using epoxy resin.