01047004

Monograph

http://onlinepubs.trb.org...y/NCHRP112Final_Report.pdf

This Innovations Deserving Exploratory Analysis project developed a mobile and robust cone penetrometer prototype with piezoelectric sensors to measure soil properties in highway pavement. Work in the initial stage focused on fabricating a prototype equipment with attention to its portability and ruggedness and other features necessary for field use. Sensors for the cone penetrometer were purchased and tested, and the original instrument design was modified to make it more rugged and sensitive. A software based on the theory of wave propagation in granular materials was developed for field data analysis. Laboratory tests on the system using two different types of soils, one fine grained and the other coarse grained, showed good results and repeatability for resilient modulus, shear modulus and Poisson's ratio. The shear moduli of the soils agree well with that calculated by Hardin and Richards equation. Work in the second stage focused on design improvement and field testing of the prototype equipment. Final design modifications to the prototype were made and the equipment was fabricated. The design modifications were aimed at making the equipment lightweight for easy handling and sensors waterproof to allow its use in wet soils. A vibration system was also introduced to help drive the penetrometer in the ground smoothly. The Ohio Department of Transportation has provided a test site in Delaware County for evaluating the equipment in the field. A commercial manufacturer has signed a memorandum of understanding with Case Western Reserve University for commercialization of the equipment.

This NCHRP-IDEA investigation was conducted by Case Western Reserve University, Cleveland, Ohio. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

TRB-NCHRP-112

English

24p

2006-10

NCHRP-IDEA Program Project Final Report

Final Report

January 2005 - July 2006

Print

Figures; Photos; References

Cone penetrometers; Equipment design; Field tests; Laboratory tests; Modulus of resilience; Piezoelectric transducers; Poisson ratio; Portable equipment; Prototype tests; Prototypes; Sensors; Shear modulus; Software; Soil tests; Technological innovations

Innovations Deserving Exploratory Analysis (IDEA) (Program)

Repeatability

Bridges and other structures; Design; Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB

Apr 26 2007 10:13AM