Engineering Guide:
Technical Articles

A plasticity index chart is used in geotechnical engineering to evaluate and classify fine-grained soils based on two laboratory-derived parameters: the Liquid Limit (LL) and the Plasticity Index (PI). The plasticity index is calculated from the Atterberg limits using the relationship: PI = LL − PL where PL is the Plastic Limit. The resulting PI represents the range of water

A foundation model cannot be defined by footing or pile geometry alone. The behaviour of a foundation depends on the ground supporting it, the loads transferred from the structure, groundwater conditions, and the way stresses and deformations develop within the soil. A foundation that provides adequate resistance against failure may still be unsuitable if the resulting settlement exceeds acceptable limits.

Calculating lateral earth pressure is only one part of designing a retaining wall. The wall must resist the actions generated by the retained soil, but its performance can also be influenced by groundwater pressure, surcharge loads, seismic effects, foundation conditions, and the structural capacity of the wall itself. Determining an earth-pressure diagram therefore does not, on its own, demonstrate that

A geotechnical investigation can produce a substantial amount of information about a site: borehole logs, soil descriptions, groundwater observations, SPT results, laboratory test data, and interpreted engineering parameters. Yet none of these inputs, on their own, define how the ground will behave beneath a foundation, behind an excavation support system, or along a potential slope failure surface. That requires an

Pile foundations are designed to transfer structural loads safely through soil layers whose behavior is often far more complex than the structure they support. Unlike steel or concrete, soil is naturally variable, and its response depends on factors such as layering, groundwater conditions, stress history, loading sequence, and the interaction between neighboring piles. As a result, predicting the performance of

Saturated unit weight of soil (γsat) is the unit weight of a soil when all of its voids are completely filled with water (degree of saturation, Sr = 100%). Expressed in kN/m³, it represents the combined weight of soil solids and pore water per unit volume under fully saturated conditions. Saturated unit weight is a fundamental parameter in geotechnical engineering

Bearing capacity describes the ability of soil to support foundation loads without experiencing shear failure or excessive deformation. In classical foundation design, this resistance is commonly expressed through bearing capacity factors—dimensionless coefficients used within bearing capacity equations to represent different components of soil resistance. The three primary factors are Nc, Nq, and Nγ, which are associated with cohesion, surcharge, and

Finite element analysis (FEA) is a numerical engineering technique used to predict how a structure, component, or physical system will behave under specific loads and boundary conditions. It works by dividing a complex model into smaller regions called finite elements, solving the governing equations for each element, and combining those results to estimate the behavior of the complete system. Engineers

The role of shallow foundations—such as isolated, strip, and raft footings—is fundamental to structural engineering, as they transfer superstructural loads directly to the upper soil strata. The safety of any structure depends not only on the structural capacity of its reinforced concrete elements, but critically on the ability of the underlying soil to support these applied stresses without undergoing shear

In deep excavation projects, one of the most critical challenges geotechnical engineers face is a high groundwater table. Retaining wall designs executed in saturated soils carry severe risks, including heavy lateral hydrostatic pressures, water seepage issues, hydraulic heave, and piping hazards. A failure like hydraulic heave or piping at the base of an excavation not only compromises the stability of

Finite element analysis has changed what engineers can model in geotechnical engineering. Complex soil–structure interaction, nonlinear soil behavior, construction stages, irregular geometries, and detailed stress and deformation patterns can all be investigated at a level that simpler analytical approaches may not provide. That capability, however, can lead to a misleading assumption: that more advanced numerical modeling is automatically the better

Excavation design becomes more complex the moment the surrounding ground has to remain stable while soil is being removed. What may appear to be a straightforward trench or excavation can quickly become a soil–structure interaction problem involving changing earth pressures, groundwater, surcharge loads, nearby structures, retaining walls, anchors, struts, and multiple construction stages. This is where trenching and shoring software

Civil engineering software covers an increasingly broad part of the engineering workflow, from structural modeling and design to project documentation. But geotechnical engineering introduces a different set of problems. Soil is not simply another structural material, and a foundation model is not the same thing as a complete understanding of the ground beneath it. So, can civil engineering software handle

Earthquake-induced ground failure is not limited to structural instability or bearing capacity problems. In saturated, loose granular soils, cyclic earthquake loading can rapidly increase pore water pressure, reducing effective stress and causing the soil to lose a significant portion of its strength and stiffness. This behavior, known as soil liquefaction, can lead to settlement, lateral deformation, loss of foundation support,

Geotechnical engineering software can cost anywhere from a few hundred dollars for a specialized calculation tool to more than $20,000 per year for advanced 3D finite element analysis platforms. The final price depends on what the software is designed to do, whether tools are sold individually or as part of a complete package, the licensing model, and the level of

In every geotechnical textbook, the friction angle of soil ($\phi$) is presented through the elegant geometry of the Mohr-Coulomb failure envelope. But as every field engineer knows, there is a vast gap between a circle on a graph and the messy reality of a borehole log. On-site, you aren’t just calculating a property; you are determining the safety of a

In high-density urban environments, shoring system design and analysis is no longer just about holding back dirt—it is about surgical precision. Whether you are excavating next to a historic building or managing deep groundwater tables, the stability of your excavation is the only thing standing between a successful project and a catastrophic structural failure. The challenge for modern engineers lies

In the specialized field of geotechnical engineering, MIDAS GTS NX has long been regarded as the “Academic Titan”—an unrivaled powerhouse for high-end finite element modeling (FEM) in Tier-1 infrastructure projects, such as subsea TBM tunnels or massive dam monitoring systems. Its capacity to resolve complex non-linear deformations and soil-structure interactions is unparalleled for purely numerical simulations. However, for the modern engineering

The landscape of civil infrastructure is undergoing a radical transformation, and at the heart of this evolution lies a fundamental shift in how we approach the earth itself. As we navigate 2026, the reliance on fragmented legacy systems is fading, replaced by a sophisticated integration of data science and structural mechanics. However, for many firms, the promise of digital transformation

In the specialized field of geotechnical engineering, PLAXIS has long been regarded as the gold standard for high-end geotechnical finite element software. Its capacity to resolve complex non-linear deformations and soil-structure interactions in multi-phase environments is unparalleled for Tier-1 infrastructure projects, such as subsea TBM tunnels or massive dam monitoring systems. However, for the boutique firm or the project manager overseeing

Geotechnical engineering is evolving toward a framework where geotechnical statistics and high-fidelity modeling enhance our traditional design methods. This shift is not about moving away from the efficiency of 2D section analysis—which remains the backbone of shoring and retaining wall design—but rather about empowering these calculations with probabilistic methods. By quantifying the inherent variability of soil properties, engineers can now