scispace - formally typeset
Search or ask a question
Journal ArticleDOI

2D numerical analysis of a cantilever retaining wall backfilled with sand–tire chips mixtures

TL;DR: In this paper, the backfill behind a retaining wall can be constructed with sand-tire chips (STC) mixture; this can lead to reduced horizontal displacements and earth pressures on the wall.
Abstract: Previous research has shown that the backfill behind a retaining wall can be constructed with sand–tire chips (STC) mixture; this can lead to reduced horizontal displacements and earth pressures on...
Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, the feasibility of reusing waste tire textile fibers (WTTFs) as reinforcement agents in an expansive soil was investigated through a comprehensive set of laboratory experiments, i.e., standard compaction, split tensile strength (STS), swelling-consolidation, volumetric shrinkage, and desiccation cracking tests.

81 citations

Journal ArticleDOI
TL;DR: Numerical simulations show that the relationship between the peak friction angle ϕp and the intermediate principal stress ratio b is influenced by the addition of rubber particles, and a suggested explanation of this phenomenon is that the rubber particles mainly affect the inherent stability of the strong network.
Abstract: Sand–rubber mixtures (SRMs) consisting of stiff sand particles and soft rubber particles are typical binary mixture materials that possess a variety of complicated properties. The complexity of the properties of sand–rubber mixtures is increased when complex stress path is involved. This study investigates the mechanical behavior of sand–rubber mixtures under generalized loading conditions using the discrete element method. A series of numerical true triaxial shear tests were conducted on pure sand and sand–rubber mixtures. The effect of rubber content and loading path on both of the macroscopic and microscopic performances of sand–rubber mixtures was investigated, and the associated microscale mechanism was also discussed. Numerical simulations show that the relationship between the peak friction angle ϕp and the intermediate principal stress ratio b is influenced by the addition of rubber particles, and a suggested explanation of this phenomenon is that the rubber particles mainly affect the inherent stability of the strong network. Particle-scale observations, including the coordinate number, the proportion of strong contacts, and the fabric anisotropy, are also presented in this study. Microscopic results confirm the explanation above, and explore the force transmission characteristics of sand–rubber mixtures under generalized loading conditions. This research can provide a reference for the constitutive model development of sand–rubber mixtures.

10 citations


Cites methods from "2D numerical analysis of a cantilev..."

  • ...Discrete element method (DEM), which was first developed by Cundall and Strack [30], has been proven to be a powerful tool in investigating the mechanical behavior of granular materials, and has been successfully applied to investigating the mechanical properties of sand–rubber mixtures [6,16,18,31] and to simulate the true triaxial shear tests [25,26,28]....

    [...]

Journal ArticleDOI
01 Mar 2021
TL;DR: In this article, a review on the use of some of the waste materials like Fly ash (FA), Bottom ash (BA), Tire derived Materials (TDM) in lieu of natural geomaterials as lightweight fills for retaining walls and embankments is presented.
Abstract: In spite of the development foreseen by our economy over this century, abundant quantity of waste materials is being generated in various sectors such as transportation, power generation and industries. Meanwhile, constructional activities across the globe demand virgin natural materials. This paper emphasis a review on the use of some of the waste materials like Fly ash (FA), Bottom ash (BA), Tire derived Materials (TDM) in lieu of natural geomaterials as lightweight fills for retaining walls and embankments. A brief review of the engineering behavior of these waste materials which makes them a competent fill material will be presented here. Further full scale and model studies of embankments and retaining walls utilizing these wastes for fill application is also emphasized. The results of these studies have shown that these waste materials can act as competent fill material for geotechnical applications.

2 citations

Journal ArticleDOI
TL;DR: Recently, population growth and more need for transportation have significantly increased the number of scrap tyres all over the world as discussed by the authors, and environmental pollution and endangered human health are serio-...
Abstract: Recently, population growth and more need for transportation have significantly increased the number of scrap tyres all over the world. Environmental pollution and endangered human health are serio...

2 citations

References
More filters
Journal ArticleDOI
TL;DR: It is argued that certain duties of patients counterbalance an otherwise unfair captivity of doctors as helpers and that vulnerability does not exclude obligation.
Abstract: There has been a shift from the general presumption that “doctor knows best” to a heightened respect for patient autonomy. Medical ethics remains one-sided, however. It tends (incorrectly) to interpret patient autonomy as mere participation in decisions, rather than a willingness to take the consequences. In this respect, medical ethics remains largely paternalistic, requiring doctors to protect patients from the consequences of their decisions. This is reflected in a one-sided account of duties in medical ethics. Medical ethics may exempt patients from obligations because they are the weaker or more vulnerable party in the doctor-patient relationship. We argue that vulnerability does not exclude obligation. We also look at others ways in which patients’ responsibilities flow from general ethics: for instance, from responsibilities to others and to the self, from duties of citizens, and from the responsibilities of those who solicit advice. Finally, we argue that certain duties of patients counterbalance an otherwise unfair captivity of doctors as helpers.

17,373 citations

Journal ArticleDOI
TL;DR: In this paper, the authors compared the performance of the shear strength reduction technique with the method of slices for a homogeneous embankment and showed that the latter is more accurate than the former.
Abstract: INTRODUCTION For slopes, the factor of safety F is traditionally de®ned as the ratio of the actual soil shear strength to the minimum shear strength required to prevent failure (Bishop, 1955). As Duncan (1996) points out, F is the factor by which the soil shear strength must be divided to bring the slope to the verge of failure. Since it is de®ned as a shear strength reduction factor, an obvious way of computing F with a ®nite element or ®nite difference program is simply to reduce the soil shear strength until collapse occurs. The resulting factor of safety is the ratio of the soil's actual shear strength to the reduced shear strength at failure. This `shear strength reduction technique' was used as early as 1975 by Zienkiewicz et al. (1975), and has since been applied by Naylor (1982), Donald & Giam (1988), Matsui & San (1992), Ugai (1989), Ugai & Leshchinsky (1995) and others. The shear strength reduction technique has a number of advantages over the method of slices for slope stability analysis. Most importantly, the critical failure surface is found automatically. Application of the technique has been limited in the past due to the long computer run times required. But with the increasing speed of desktop computers, the technique is becoming a reasonable alternative to the method of slices, and is being used increasingly in engineering practice. However, there has been little investigation of the accuracy of the technique. In this paper, factors of safety obtained with the shear strength reduction technique are compared to limit analysis solutions for a homogeneous embankment.

938 citations


"2D numerical analysis of a cantilev..." refers result in this paper

  • ...According to Dawson, Roth, and Drescher (1999), the factors of safety calculated from this approach are very close to the values obtained from conventional methods in geotechnical analysis....

    [...]

Journal ArticleDOI
TL;DR: In this paper, a shear strength reduction technique for finite element slope stability analysis was developed by the authors, where the slope failure is defined according to the shear strain failure criterion.

674 citations

01 Apr 1998
TL;DR: In this article, the authors developed a concise, easy-to-use manual containing the latest available information on the use of waste or by-product materials in pavement construction applications, including past performance, engineering properties, processing requirements, design and construction, and unresolved issues.
Abstract: The objective of this project was to develop a concise, easy-to-use manual containing the latest available information on the use of waste or by-product materials in pavement construction applications. The manual provides technical guidance for highway and materials engineers, waste and by-product generators, and others involved in making decisions regarding the use of waste and by-product materials in highway construction. The manual covers nineteen waste and by-product materials from the domestic, industrial, and mining sectors and six high-volume pavement construction applications. For each material, information on material origin, sources, and properties is provided. In addition, application-specific information (for specific material-application combinations) is provided, including past performance, engineering properties, processing requirements, design and construction, and unresolved issues. General guidance on environmental and cost issues, and a general outline on determining the suitability of a material in an application, are also provided. The manual is distributed in loose-leaf format for ease of use and to allow future updates and expansion.

298 citations

Journal ArticleDOI
TL;DR: The volume of scrap tires, an undesired urban waste, is increasing every year and one of the possible alternatives for this waste is to use shredded tires alone or mixed with soil as a lightweight bac... as discussed by the authors.
Abstract: The volume of scrap tires, an undesired urban waste, is increasing every year. One of the possible alternatives for this waste is to use shredded tires alone or mixed with soil as a lightweight bac...

207 citations


"2D numerical analysis of a cantilev..." refers result in this paper

  • ...…be noted that the engineering properties of STC mixtures obtained by Ahmed (1993) differ from those recorded by previous investigators (Reddy, Kumar, & Krishna, 2015; Youwai & Bergado, 2003) because of differences in the sizes and shapes of shredded tire chips and the sample preparation procedures....

    [...]