IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

This study documents the measurement of normal stresses and stress relaxation in sand-asphalt mixtures fabricated with different fillers and asphalts during torsion. Hydrated lime and limestone fillers and asphalts graded as PG64-22 and AC-30 (from Sinclair (Wyoming), Crown (Nevada), and Crown (Canada)) are used in the fabrication of the sand-asphalt mixtures. The specimens are tested in a torsional rheometer. The experimental results clearly show that the normal stresses that are developed are quite significant even for specimens tested at very low rotational rates. Also, asphalts from different sources show differences in peak normal stresses and in their relaxation pattern. The measurement of significant normal stresses is a reflection of the nonlinear character of the material and warrants the development of nonlinear constitutive models for describing their behavior. Copyright © Taylor &amp; Francis Group, LLC.

Department of Mechanical Engineering

World University root node

Particulate Science and Technology

An experimental investigation into the influence of fillers on the development of normal stresses and stress relaxation in asphalt mixtures due to torsion

There is sparse documentation of the large normal stresses that develop in asphalt mixtures subjected to shear, a typical characteristic of non-linear materials. In this study, we continue our initial investigations of using a torsional rheometer for measuring the normal stresses developed in asphalt mixtures when subjected to torsion. Samples of sand-asphalt mixture are subjected to rotation rates as low as one revolution in ninety minutes. This study provides further clear evidence of significant development of normal stresses due to shearing and emphasizes the need for the development of models that can describe such a phenomenon. © 2007 Elsevier Ltd. All rights reserved.

Department Of Civil Engineering

Mechanics Research Communications

Characterization of the non-linear response of asphalt mixtures using a torsional rheometer

Efficacy of engineering design education in an interdisciplinary team-based course setting, with exposure to the broader concerns of business, finance and management, interests many educators. This paper reports on the use of design knowledge assessment patterned after the Transferable Integrated Design Engineering Education (TIDEE) Design Team Readiness Assessment (DTRA) I and II [1,2,3,4] to evaluate what aerospace, mechanical, electrical and computer science students learned about engineering design as a result of participating in a Boeing-supported, two-semester, project-based senior capstone design course at Texas A&M University. The Boeing course sequence was designed to provide students with the experience of working in multi-disciplinary teams on a design and implementation project while receiving instruction in elements of project management from a business perspective. Students were assessed using rubric-based instruments and customized team design simulation procedures similar to Parts I & II of the TIDEE Design Knowledge Assessment at the beginning and at the end of their senior capstone design project. This paper will discuss the lessons learned about the design knowledge assessment process to measure the preparedness of students at the beginning of the capstone design class and the evolution of their understanding of the design process at the end of the twosemesters of course work. Pre-to-post treatment group comparisons and control group comparisons were used in the assessment design, which also compared the rubric-based assessment with content analysis of students' written responses to assessment questions. Results indicated that the content analysis was more effective in capturing students' increased understanding of the design process, and the reasons for this are explored. Specific changes for improving the assessment process have been implemented for the project in the 2005-06 academic year. © American Society for Engineering Education, 2006.

ASEE Annual Conference and Exposition, Conference Proceedings

Lessons learned in assessing senior engineering capstone design course learning with a variation on the TIDEE design team readiness assessment (DTRA) I and II

Burgers [Mechanical considerations - model systems - phenomenological theories of relaxation and of viscosity, in: J.M. Burgers (Ed.), First Report on Viscosity and Plasticity, Nordemann Publishing Company New York, 1935] introduced a viscoelastic fluid model to describe the response of materials such as asphalt that also enjoys a good deal of popularity in the field of geomechanics. An instrument that has been developed to characterize the material moduli of such viscoelastic fluids is the orthogonal rheometer which is essentially two parallel plates rotating about non-coincident axes, but with the same angular speed. Flows of a variety of non-Newtonian fluids have been studied in such an instrument. Here, we are able to obtain an exact solution for the flow of a Burgers' fluid in an orthogonal rheometer. We show that pronounced boundary layers can develop during flows of such a fluid due to a variety of reasons. © 2004 Elsevier Ltd. All rights reserved.

International Journal of Engineering Science

A note on the flow of a Burgers' fluid in an orthogonal rheometer

The present work is an extension of the investigations performed by <a href="https://www.tandfonline.com/doi/full/10.1080/02726350490501529#">Massoudi and Anand (2001)</a>. The free surface flow problem is studied here. Numerical solutions for steady free surface flow of a solid-fluid mixture down an inclined plane are presented. The problem is formulated using the mixture theory framework. The resulting set of three coupled nonlinear differential equations is nondimensionalized. A parametric study is conducted to understand the influence of the dimensionless numbers on the velocity and volume fraction. The maximum fluid velocity is found to decrease with increase in the ratio of the drag force to the viscous forces within the fluid phase (D1). The fluid phase velocity was found to decrease with increase in the ratio of the drag force to viscous force within the solid component (D2), and the corresponding solid phase velocity was found to increase.

Steady Free Surface Flow of a Fluid-Solid Mixture Down an Inclined Plane

The BANKS system supports keyword search on databases storing structured/semi-structured data. Answers to keyword queries are ranked. As in Information Retrieval (IR) systems, the top answers may not be exactly what a user is looking for. Further interaction with the system is required to narrow in on desired answers. We describe some of the new features that we have added to the BANKS system to improve user interaction. These include an extended query model, richer support for user feedback and better display of answers.