Geotechnical investigation, in hilly areas, for high-rise projects, becomes a problematic issue and costly process due to difficulties in mobilization and assembling the drilling equipment on mountainous terrains. The objective of this study is to map soil properties of study areas, especially at inaccessible sites, for reconnaissance. Digital soil maps for Tehsil Murree, Pakistan, have been developed using the emerging Geographical Information System (GIS). The research work involved the creation of an exhaustive database, by collecting and rectifying geotechnical data, followed by the digitization of the acquired data through integration with GIS, in an attempt to visualize, analyze and interpret the collected geotechnical information spatially. The soil data of 205 explanatory holes were collected from the available geotechnical investigation (GI) reports. The collection depth of soil samples, which were initially used for the design of deep and shallow foundations by different soil consultancies in the Murree area, was approximately 50 ft. below ground level. Appropriate spatial interpolation methods (i.e., the Kriging) were applied for the preparation of smooth surface maps of soil standard penetration tester number values, soil type and plasticity index. The accuracy of developed SPT N value and plasticity maps were then evaluated using the linear regression method, in which the predicted values of soil characteristics from developed maps and actual values were compared. SPT N value maps were developed up to a depth of 9.14 m below ground level and at every 1.52 m interval. The depth of refusal was considered in the developed maps. Soil type and plasticity maps were generated up to 15.24 m depth, again at every 1.52 m intervals, using color contours, considering the maximum predicted foundation depth for high-rise projects. The study has implications for academics and practitioners to map the soil properties for inaccessible sites using GIS, as the resulting maps have high accuracy.

This study presents a cost-based optimization model for the design of isolated foundations in cohesive soils. The optimization algorithm not only incorporates safety requirements in the form of ultimate limit state (ULS) and serviceability limit state (SLS) criteria but also deals with the economics simultaneously. In that regard, the generalized reduced gradient (GRG) method is used for the optimization purpose to achieve the least construction cost of an isolated foundation along with the integration of design parameters as optimization variables. The optimization technique is elaborated using a design example in silty clayey soil and the results of the optimized design are compared with those of the conventional design. The optimization model shows that the optimized design can reduce the construction cost by up to 44% as compared to the conventional design cost for the particular example. Moreover, a sensitivity analysis is also performed to evaluate the quantitative impact of cohesive soil properties, design load, and groundwater table on the construction cost. The results indicate that the construction cost majorly depends on the combined effect of four key parameters: Young’s modulus, recompression index, design load, and groundwater table.

This paper addresses the issues in making wood–concrete composites more resilient to environmental conditions and to improve their compressive strength. Tests were carried out on cubic specimens of 10 × 10 × 10 cm³ composed of ordinary concrete with a 2% redwood- and hardwood-chip dosage. Superficial treatments of cement and lime were applied to the wood chips. All specimens were kept for 28 days in the open air and for 12 months in: the open air, drinking water, seawater, and an oven. Consequently, the compressive strength of ordinary concrete is approximately 37.1 MPa. After 365 days of exposure to the open air, drinking water, seawater, and the oven, a resistance loss of 35.84, 36.06, 42.85, and 52.30% were observed, respectively. In all environments investigated, the untreated wood composite concrete’s resistance decreased significantly, while the cement/lime treatment of the wood enhanced them. However, only 15.5 MPa and 14.6 MPa were attained after the first 28 days in the cases of the redwood and the hardwood treated with lime. These findings indicate that the resistance of wood–concrete composites depends on the type of wood used. Treating wood chips with cement is a potential method for making these materials resistant in conservation situations determined by the cement’s chemical composition. The current study has implications for researchers and practitioners for further understanding the impact of these eco-friendly concretes in the construction industry.

Le Liban se caractérise par ses hautes montagnes fortement urbanisées. Traversé par plusieurs failles principales et secondaires, ce pays présente de forts risques sismiques. Il a déjà subi plusieurs tremblements de terre destructeurs. Dans le futur, on craint un tremblement de terre majeur. Face à une telle situation, il est nécessaire de mener des travaux de recherche pour analyser ce risque. Ce travail de thèse s’inscrit dans ce cadre. Le travail est réalisé à l’aide d’une modélisation numérique avancée fondée sur la méthode des éléments distincts. Les études ont été effectuées à l’aide du code de calcul (UDEC). Les analyses sont établies sur des cas réels identifiés à partir de plusieurs visites de terrain. Un travail important a été aussi consacré à la collecte des informations relatives aux propriétés mécaniques des matériaux. La première partie de la thèse est consacrée à une synthèse bibliographique en rappelant les paramètres qui caractérisent la géométrie des discontinuités des massifs rocheux et leur comportement mécanique en compression et en cisaillement. Des méthodes d’analyse de la stabilité des milieux rocheux fissurés et quelques exemples réels publiés dans la littérature sont exposés. La seconde partie comporte des analyses sismiques menées sur un massif du site de Jezzine au Liban Sud. Les modélisations traitent différentes configurations : massif sans fractures, massif avec fractures horizontales et massif avec un réseau de fractures horizontales et verticales. On présente également les résultats obtenus avec un renforcement du massif par ancrage. La dernière partie présente une étude de l’influence de la présence de l’eau sur le comportement sismique des massifs rocheux.

Seismic events can severely impact earth-retaining structures near deep excavations, disrupting operations, especially in densely populated areas during emergencies and rescue efforts. Rapid assessment of seismic vulnerability is essential for these structures. Fragility curves are effective tools for evaluating earthquake-induced damage. This study focuses on developing fragility functions for embedded cantilever retaining walls. A key innovation of this research is identifying intensity measures (IMs) that strongly correlate with wall responses, addressing gaps in current seismic vulnerability assessments. The study employs an advanced approach by combining static simulations with two-dimensional (2D) dynamic analysis using Plaxis 2D software, allowing an accurate representation of the wall behaviour under earthquake. Thirty-one IMs were evaluated for norms such as efficiency, practicality, proficiency, and sufficiency, resulting in the selection of optimal IMs for the fragility functions. The response of the structure is characterised by a permanent lateral displacement at the top of the wall. Fragility functions were developed for the spectral acceleration, providing a unique tool for assessing the seismic vulnerability of embedded cantilever retaining walls. These proposed tools serve as valuable resources for emergency management and preparedness, aiding in the identification of priority actions and appropriate measures for mitigating seismic risk.