This research includes the potential for resistance and the expansion that the soil presents, this evaluation was carried out through CBR tests. The soil cement technique was used to improve the physical and mechanical characteristics; this process consists in mixing the material with Portland cement type I. That combination forms soil cement 10%, 15% y 20%, which present an increase of the CBR (max: 138.7% and min: 91.9%) achieving a type of extraordinary subgrade to resist the structure of the pavement and a reduction of 7.18% in the expansion of the samples.

Cement Kiln Dust (CKD) and Micronized Rubber Powder (MRP) offer sustainable solutions for soil stabilization, addressing both environmental and engineering challenges. CKD, a byproduct of cement manufacturing, is rich in pozzolanic materials that can enhance clayey soil properties by reducing plasticity and increasing strength. This makes CKD a valuable additive for improving the load-bearing capacity and durability of clayey soils used in construction. MRP, derived from end-of-life tires, contributes to sustainability by recycling waste rubber and adding ductility to treated soils. The incorporation of rubber waste not only helps in reducing the environmental burden of tire disposal but also enhances the flexibility and resilience of the stabilized clayey soil. Utilizing these industrial by-products in soil stabilization not only mitigates waste disposal issues but also promotes the development of resilient and eco-friendly construction materials, making them highly beneficial for sustainable infrastructure projects.The present study investigates the effects of various mix proportions of CKD and MRP on Carbondale soil, a high plastic clay. The soil was stabilized with CKD in proportions of 7%, 14%, and 21%, and MRP in proportions of 0%, 2.5%, 5%, and 10% of the dry unit weight of clayey soil. Comprehensive laboratory tests were conducted, including particle size distribution, Atterberg limits, compaction characteristics using the miniature Proctor, unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV), and resilient modulus (RM). The RM test assessed the soil's elasticity under repeated loading, simulating traffic conditions to evaluate the material's performance in pavement design. These tests aimed to determine the optimal mix proportions that would provide the best combination of strength, stiffness, and durability for use in various geotechnical applications. Results from different tests showed that the addition of MRP significantly altered the properties of the CKD-stabilized soil mix. The miniature Proctor test revealed that the addition of MRP reduced the maximum dry density (MDD) of the mix and slightly increased the optimum moisture content (OMC) of the soil mix, indicating a change in compaction characteristics. From the UCS test, it was observed that while the addition of 2.5% MRP to the CKD soil mix reduced the overall strength, it absorbed considerable amount of strain. Specifically, for soil mixed with 7% CKD, the inclusion of 2.5% MRP absorbed over 60% more strain, despite a 50% reduction in strength. Similarly, the mix with 21% CKD and 2.5% MRP showed a 30% increase in peak strain with a strength reduction of up to 40%. The resilient modulus values indicated that the addition of MRP to the soil mix resulted in strain softening, leading to decreased RM values. The soil mix with 7% CKD and 2.5% MRP showed almost no gain in RM values across all curing periods due to strain softening effects. However, the regression analysis between predicted and experimental RM values showed a positive correlation, with a coefficient of determination (R2) ranging from 0.7 to 0.96, indicating a reliable predictive model for RM based on the tested parameters. These findings highlight the trade-offs between strength and stiffness in CKD and MRP-stabilized soils, offering insights for optimizing soil stabilization techniques in sustainable construction practices

Drilled shaft retaining walls are common earth retaining structures, well suited to urban environments where noise, space, and damage to adjacent structures are major considerations. The design of drilled shaft retaining walls in non-expansive soils is well established. In expansive soils, however, there is no consensus on the correct way to account for the influence of soil expansion on wall behavior. Based on the range of design assumptions currently in practice, existing walls could be substantially over- or under-designed. The goal of this research is to advance the understanding of the effects of expansive clay on drilled shaft retaining walls. The main objectives of this study are to identify the processes responsible for wall loading and deformation in expansive clay, to evaluate how these processes change with time, and to provide guidance for design practice to account for these processes and ensure adequate wall performance. The primary source of information for this research is performance data from a four-year monitoring program at the Lymon C. Reese research wall, a full-scale instrumented drilled shaft retaining wall constructed through expansive clay in Manor, Texas. The test wall was instrumented with inclinometers and fiber optic strain gauges, and performance data was recorded during construction, excavation, during natural moisture fluctuations, and during controlled inundation tests that provided the retained soil with unlimited access to water. In addition to the test wall study, a field assessment of existing TxDOT drilled shaft retaining walls was conducted. The main process influencing short-term wall deformation was found to be global response to stress relief during excavation, which causes the wall and soil to move together without the development of large earth pressures or bending stresses. Long-term wall deformations were governed by the development of drained conditions in both the retained soil and the foundation soil after approximately eight months of controlled inundation testing. To ensure adequate wall performance, the deformations and structural loads associated with short- and long-term conditions should be combined and checked against allowable values. / text

Mechanical properties of marine sediment near Koper and numerical modelling of a deep excavation Engineering geological conditions near the port Koper in southwestern Slovenia forces geotechnical experts and civil engineers to solve problems in foundation various types of objects and purpose of the practice since the fifties of last century, when it began an intensive development of infrastructure of the port. The results of series of geological and geotechnical surveys, monitoring, and long experience with foundation in the local geology shows that it is almost always the 3rd geotechnical category, or foundation of complex structures in difficult geological conditions below the water table. The entire area belongs to Alpine-Dinaric tectonic area. The rock foundation is composed of complexes of flysch sediments Eocene age at which mounted files of recent marine sediments in the area widely submerged river valley fluvial sands and gravels. From the geotechnical point of view it is interesting site, where most buildings were based on a layer of soft marine sediments, where it is through the creation of special methods implemented in the establishment of deep-level endurable layers of gravel and sand of the river Rižana or at the level footingwall flysch. Set of marine sediments near the port Koper,...