Fundamentals of soil stabilization Firoozi, Ali Akbar; Guney Olgun, C.; Firoozi, Ali Asghar ...
International journal of geo-engineering,
12/2017, Letnik:
8, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Clayey soils are usually stiff when they are dry and give up their stiffness as they become saturated. Soft clays are associated with low compressive strength and excessive settlement. This reduction ...in strength due to moisture leads to severe damages to buildings and foundations. The soil behavior can be a challenge to the designer build infrastructure plans to on clay deposits. The damage due to the expansive soils every year is expected to be $1 billion in the USA, £150 million in the UK, and many billions of pounds worldwide. The damages associated with expansive soils are not because of the lack of inadequate engineering solutions but to the failure to identify the existence and magnitude of expansion of these soils in the early stage of project planning. One of the methods for soil improvement is that the problematic soil is replaced by suitable soil. The high cost involved in this method has led researchers to identify alternative methods, and soil stabilization with different additives is one of those methods. Recently, modern scientific techniques of soil stabilization are on offer for this purpose. Stabilized soil is a composite material that is obtained from the combination and optimization of properties of constituent materials. Adding cementing agents such as lime, cement and industrial byproducts like fly ash and slag, with soil results in improved geotechnical properties. However, during the past few decades, a number of cases have been reported where sulfate-rich soils stabilized by cement or lime underwent a significant amount of heave leading to pavement failure. This research paper addressed the some fundamental and success soil improvement that used in civil engineering field.
Amid rising global demand for sustainable energy, wind energy emerges as a crucial renewable resource, with the aerodynamic optimization of wind turbine blades playing a key role in enhancing energy ...efficiency. This systematic review scrutinizes recent advancements in blade aerodynamics, focusing on the integration of cutting-edge aerodynamic profiles, variable pitch and twist technologies, and innovative materials. It extensively explores the impact of Computational Fluid Dynamics (CFD) and Artificial Intelligence (AI) on blade design enhancements, illustrating their significant contributions to aerodynamic efficiency improvements. By reviewing research from the last decade, this paper provides a comprehensive overview of current trends, addresses ongoing challenges, and suggests potential future developments in wind turbine blade optimization. Aimed at researchers, engineers, and policymakers, this review serves as a crucial resource, guiding further innovations and aligning with global renewable energy objectives. Ultimately, this work seeks to facilitate technological advancements that enhance the efficiency and viability of wind energy solutions.
Bridges are among the most important transportation elements that may be damaged by earthquakes. An integral abutment bridge (IAB) is a bridge linking the superstructure directly to the substructure. ...As soil piles, abutments, and superstructures act as a combined system to resist lateral loading on the bridge, soil stiffness has a major impact on load distribution. This research attempts to determine how the structure and soil parameters affect the IABs. The parametric study consists of four variables, namely bridge span (short, medium, and large spans were 18.3, 35.4, and 64.5 m, respectively), backfill height/pressure (3.1, 4.6, and 6.1 m, respectively), stiffness of soil mixture backfills (high, intermediate, and low), and soil density around the piles (high, intermediate, and low). Because of the small width–length ratio of the bridge, a 2D model of an IAB with soil springs around the piles and abutments was developed with finite element software. Findings show that the value of the backfill pressure affects girder axial forces and girder bending moments at the IAB. Also, the stiffness of soil mixture backfills is an important factor to change lateral displacements, while less movement is related to high stiffness of soil mixture backfills with intermediate clay around the pile. It is clear that the maximum axial girder moments at the superstructure generally decrease when the stiffness of the soil mixture behind the abutments and around piles increases, similar to pile deflection and abutment displacements. In addition to maximum abutment, the head moment decreases when abutment backfill is dense and increases when piles are located in hard clay, similar to pile moments. Lastly, dense sand backfill behind abutments is recommended since it decreases pile deflections, pile lateral forces, abutment displacements, abutment head moments, and particularly pile bending moments.
This systematic review, not financially supported by any funding body, aims to synthesize the current knowledge on the applications, potential benefits, and challenges of 4D printing in civil ...engineering, with a focus on its role in sustainable solutions. Comprehensive searches were conducted in Scopus, Web of Science, and Google Scholar using related keywords. Articles that discussed 4D printing within civil engineering and construction contexts, encompassing both conceptual and empirical studies, were included. The findings suggest that 4D printing, with its time-responsive transformation feature, can enhance design freedom, improve structural performance, and increase environmental efficiency in construction. However, challenges persist in material performance, scalability, and cost. Despite these, ongoing advancements signal potential future developments that could widen the opportunities for large-scale applications of 4D printing in civil engineering. The potential use of renewable, bio-based materials could also lead to more sustainable construction practices. This review highlights the transformative potential of 4D printing, underlining the need for further research to fully leverage its capabilities and address current limitations. 4D printing emerges as a promising avenue for sustainable civil engineering solutions, offering a transformative approach that calls for continued exploration and development.
Mixing of nano-sized powders with soils (macro-sized powders) is a noteworthy issue for geotechnical projects. Thus, this study examined the horizontal ball mill mixing of nano-copper oxide with ...kaolinite. Ball milling parameters (rotation speed, weight ratio of balls to powder and milling time) of the planetary ball milling were optimized for proper mixing of nano-copper oxide and kaolinite powder. Results showed that increase in mixing time decreased the agglomeration of nano-copper powders and kaolinite and increased the homogeneity of nano-copper powder with kaolinite particles. The quality of mixing was assessed through intensity and scale of segregation using concentration data obtained through energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses. It was observed through these two tests that, increase in ball milling time after 6 hours resulted in grain size reduction. Field emission scanning electron microscopy analysis showed that nano-coppers were regularly found on the surface of kaolinite particles after 6 hrs. of horizontal milling at 4:1 ratio of balls to powder mixture. Furthermore, 24 hrs. mixing resulted in grinding of kaolinite particles and hence their size was reduced. Particle size analysis confirmed these results, as the highest size span value of 3.417 was observed after 6 hrs. milling with speed of 200 rpm.
In the face of mounting geotechnical challenges within urban centers worldwide, the significance of engineering solutions extends beyond the immediate resolution of these issues to act as catalysts ...for socio-economic development. This paper examines specific geotechnical problems, such as soil instability and the underutilization of urban green spaces, and their direct impact on community health, safety, and the quality of urban life. With a focus on diverse international case studies, the research clarifies the reciprocal influence between geotechnical innovation and socio-economic advancements. It advocates for the integration of geotechnical practices into the broader scope of urban planning, detailing how cities can leverage these practices for sustainable growth and enhanced community well-being.
Bridges are one of the most critical parts of transportation networks that may suffer damages against earthquakes. Also, seismic responses of most bridges are significantly influenced by ...soil-structure interaction effects. Taking out expansion joints in the bridges may cause many difficulties in design and analysis due to the complexity of soil-structure interaction and nonlinear behavior. The secondary loads on an IAB include seismic load, temperature variation, creep, shrinkage, backfill pressure on back wall and abutment, all of which cause superstructure length and stress variations in girder changes. The purpose of this study is to recognize the most effective parameters of analysis IABs. Findings show that the backfill material behind the IABs has a significant effect on the performance of IABs. Using a compressible material behind the abutments would enhance the in-service performance of IABs. Finally, behaviour of abutment may be greatly affected by thermal load and soil pressure. Thermal expansion coefficient significantly influences girder axial force, girder bending moment, and pile head/abutment displacement.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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