Location

Chicago, Illinois

Date

02 May 2013, 4:00 pm - 6:00 pm

Abstract

Well-built and maintained roads play a major role in the development of a nation. Hence considerable attention is required towards the widening of roads, their stability and periodic repair works. Since the beginning of modern highways, engineers have strived continuously to produce better pavement at lower cost. Most state highways in the central part of India have problems of foundation due to presence of expansive soil i.e. black cotton soil. For the improvement of such problematic soil, conventional technique of soil stabilization, use of cushion, use of moisture barriers, etc. has been adopted. The main objective of the research work was to study the typical characteristic of expansive soil and to control the swelling of expansive soil below flexible pavements. To achieve this aim work has been carried out with reinforcing geotextile overlain with cushion material. Effect of cushion material on swelling of expansive soil has been investigated alongwith the ability of geotextiles in locked and unlocked condition with cushion material was scrutinized. Better cushioning due to use of flyash can be attributed to pozzolanic activity forming stable compounds. It is observed that the use of flyash as cushion material provides better swelling control as compared to quarry dust. Unlocked geotextiles did not prove as effective as locked textiles with the use of either of the cushion materials. The unlocked textiles proved advantageous with quarry dust but did not prove as advantageous as only flyash. The most important two functions of geotextiles namely separating and reinforcement have been most effectively used in the locked condition. The study was further extended to stabilize the expansive soil with metakaolin. Swell pressure test and UCS results on samples treated using 1% metakaolin provided its effectiveness in controlling the swelling characteristics of expansive soil as well as strength improvement.

Department(s)

Civil, Architectural and Environmental Engineering

Meeting Name

7th Conference of the International Conference on Case Histories in Geotechnical Engineering

Publisher

Missouri University of Science and Technology

Document Version

Final Version

Rights

© 2013 Missouri University of Science and Technology, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Apr 29th, 12:00 AM May 4th, 12:00 AM

Study of Typical Characteristics of Expansive Subgrade With Geotextiles and Cushion Materials

Chicago, Illinois

Well-built and maintained roads play a major role in the development of a nation. Hence considerable attention is required towards the widening of roads, their stability and periodic repair works. Since the beginning of modern highways, engineers have strived continuously to produce better pavement at lower cost. Most state highways in the central part of India have problems of foundation due to presence of expansive soil i.e. black cotton soil. For the improvement of such problematic soil, conventional technique of soil stabilization, use of cushion, use of moisture barriers, etc. has been adopted. The main objective of the research work was to study the typical characteristic of expansive soil and to control the swelling of expansive soil below flexible pavements. To achieve this aim work has been carried out with reinforcing geotextile overlain with cushion material. Effect of cushion material on swelling of expansive soil has been investigated alongwith the ability of geotextiles in locked and unlocked condition with cushion material was scrutinized. Better cushioning due to use of flyash can be attributed to pozzolanic activity forming stable compounds. It is observed that the use of flyash as cushion material provides better swelling control as compared to quarry dust. Unlocked geotextiles did not prove as effective as locked textiles with the use of either of the cushion materials. The unlocked textiles proved advantageous with quarry dust but did not prove as advantageous as only flyash. The most important two functions of geotextiles namely separating and reinforcement have been most effectively used in the locked condition. The study was further extended to stabilize the expansive soil with metakaolin. Swell pressure test and UCS results on samples treated using 1% metakaolin provided its effectiveness in controlling the swelling characteristics of expansive soil as well as strength improvement.