Accurate inversion of geotechnical parameters is essential for assessing foundation-bearing capacity and stability, which directly impact structural safety and serviceability. Accurate prediction of load settlement behavior is crucial to prevent overdesign and underperformance, ensuring that foundations support anticipated loads without excessive deformation or failure. This paper presents an integrated optimization system combining ABAQUS (2022), Python (PyCharm21.3.3), and MATLAB (2022b) software, based on the Duncan-Chang (DC) model, for inversion of key geotechnical parameters. The ABAQUS UMAT subroutine customizes the DC model, facilitating its application in finite element simulations for soil-structure interaction analysis. To improve the optimization process, an adaptive genetic algorithm that dynamically adjusts crossover and mutation rates, thereby improving solution searches and parameter space exploration, is implemented. Key parameters of the DC model-the initial tangent stiffness (K) and nonlinear deformation characteristics (n) of soil-are inverted. The accuracy of this inversion is validated through comparisons with experimental pressure-settlement curves obtained from indoor bearing plate tests. Therefore, this optimization system effectively integrates intelligent algorithms with finite element analysis, serving as a reliable tool for precise geotechnical parameter inversion, with potential for improving foundation design accuracy, optimizing soil-structure interaction predictions, and improving the overall stability and safety of geotechnical structures.

The application of microorganisms to improve the mechanical properties of soil is a new developing research area. A new native bacteria extracted from soil was introduced for the biological improvement of soil geotechnical parameters. The isolate was identified as Acinetobacter calcoaceticus S1. Sporosarcina pasteurii was used as a positive control. Direct shear tests were performed on the nontreated soil and soils treated with bacteria to determine the shear strength, adhesion and angle of internal friction. The treatment period was 40 days. The shear wave velocity was measured.The results showed that the untreated sample had relatively constant shear strength, but the shear strength of the treated soils increased significantly. The soil treated with A. calcoaceticus had greater shear strength. The angle of internal friction increased for the treated soils with A. calcoaceticus (39.3%) and S. pasteurii (28.6%). The greatest cohesion was found for soil treated with A. calcoaceticus, reaching 0.66 and 0.56 kg/cm2 for S. pasteurii. The shear wave velocity in the treated soils increased significantly. The results confirmed the ability of native A. calcoaceticus to improve soil geotechnical parameters. Calcium carbonate precipitation fills the voids between soil particles and forms a gel, which makes effective connections between soil particles and makes them coalesce and grow larger.

The shallow seismic methods, including seismic refraction and 1D MASW, were used to investigate the shallow soil in the vicinity of five damaged building blocks in the village of El-Kalaheen. These building blocks exhibited structural problems including cracks, fissures and displacements between neighboring buildings. The results of both methods show that the shallow subsurface consists of two layers: a surface layer of loose sands, gravels, silts and clays and a compacted sandy clay layer that forms the bedrock in the area. The resulting seismic velocities were used to calculate the geotechnical parameters of the two layers, including Poisson's ratio, shear modulus, Young's modulus, material index and N-value. In addition, the shear wave velocities resulting from the 1D MASW method were used to calculate the average Vs30 in the site. The calculated values of the geotechnical parameters show a gradual increase in the competence of the upper layer from fairly competent and loose in the south of the area to competent and denser in the north. The geotechnical parameters of the bedrock also show an increase from moderately competent in the south to denser and more competent in the north. Possible zones of weakness are also observed in the southern part of the site. The calculated Vs30 indicates a site with stiff soil classification.

The growing popularity of GIS technology in Ethiopia has encouraged multiple scholars to investigate landslide hazards using quantitative approaches, despite its limitations. The present review examined the approach used in the evaluation of landslide hazards by five prior studies that shared catchments. The review results reveal that the controlling factors assumed by the five researchers were inconsistent and resulted in highly divergent frequency ratio (FR) values, even for the same factors. This implies that the contribution of a single instability factor can be inferred sufficiently for landslide hazard assessment and mapping; otherwise, the results are highly subjective and disputable. Since the soil type in the region was alluvial-colluvial in the five studies, and a majority of the failures occurred shortly after rainfall, rainfall data and basic soil properties (classification and shear strength) should not be overlooked. In addition to the nonstandard use of morphometric parameters, the inherent limits of GIS methodologies, the omission of hydrogeotechnical properties, and the observed subjective outcomes make the GIS-based approach imprecise, error-prone, and doubtful. The total effect will result in ineffective early warning systems and unworthy mitigation measures, resulting in significant life costs and damage. As a result, it is recommended that GIS technology should be coupled with software (TRIGRS, Scoops3D, SINMAP, OpenLISEM, GLM, and SLIP) that considers hydrogeotechnical properties to provide more reliable conclusions. In addition to using instability factors consistently, regional statistical correlations of all morphometric parameters can be developed, allowing for less complex and realistic empirical models to be used.