Conference Papers

Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506

Browse

Subject: search.filters.subject.California bearing ratio

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    PFWD, CBR and DCP evaluation of lateritic subgrades of Dakshina Kannada, India
    (2008) Nageshwar Rao, Ch.; George, G.; Shivashankar, R.
    The performance of pavements depends to a large extent on the strength and stiffness of the subgrades. Among the various methods of evaluating the subgrade strength, the use of portable falling weight deflectometers (PFWD) is gaining popularity in the recent years. This is due to its simplicity in design, portability, and the added advantages of providing quick and reliable estimates of the Young's modulus of elasticity of pavement subgrades. Hence it was felt that there is a need to study the correlation between results obtained using the PFWD and those obtained using the traditional approaches such as the California bearing ratio (CBR) test, the dynamic cone penetrometer (DCP) test. The work described herein focuses on exploring the correlations between the results obtained using the PFWD, and the results obtained using the CBR method and DCP for lateritic soils at various locations of Dakshina Kannada district of the State of Karnataka, India. Regression models were developed as part of this study to enable the prediction of CBR values based on the average of observed values of the Young's modulus obtained using the PFWD (Epfwd), and prediction of Epfwd from the average penetration-rates of DCPs performed for field density, and field-moisture content.
  • No Thumbnail Available
    Item
    Experimental Investigations on RBI Grade 81 Stabilized Lateritic Soil
    (Springer Science and Business Media Deutschland GmbH, 2021) Chethan, B.A.; Das, S.; Amulya, S.; Ravi Shankar, A.U.R.
    The effectiveness of the addition of RBI Grade 81 (stabilizer) (dosages of 2, 4, 6, and 8%) to stabilize the largely encountered lateritic soil during construction was investigated. Stabilized lateritic soil mixes were evaluated by conducting a series of experiments, viz., standard and modified compaction, unconfined compressive strength, and California bearing ratio at various curing periods. Mixes under both standard and modified compaction energies have shown the highest density at a 6% stabilizer dosage. A remarkable increase in unconfined compressive strength was observed for the specimens prepared at a 6% stabilizer dosage corresponding to the modified compaction density. An increase in the percentage of stabilizer has increased the California bearing ratio of treated mixes. Exorbitant increase in the soaked California bearing ratio values of the stabilized mixes was observed for higher dosages (6 and 8%). Hence, RBI Grade 81 amended lateritic soil mixes enhance the strength of the subgrade. © 2021, Springer Nature Singapore Pte Ltd.
  • No Thumbnail Available
    Item
    Influence of Jute Reinforcement on the Stiffness Capacity of Cohesionless Pavement Geomaterials
    (Springer Science and Business Media Deutschland GmbH, 2024) Kumar, P.; Kumar, Y.; Trivedi, A.
    In this work, cohesionless pavement geomaterial reinforced with multi-layers of georeinforcement as jute fibres has been studied. The present work is carried out on unreinforced soil and jute fibre-reinforced soil to investigate the strength and stiffness capacity of pavement geomaterials using the California bearing ratio (CBR) test. The number of layers, optimum depth, and placement of the georeinforcement in geomaterial are investigated. The embedment depth of jute fibre, i.e. D/2, D/3, and D/4 in single, double, and triple layers has been optimized using CBR values. A novel concept of stiffness capacity along with penetration factor is introduced to evaluate the strength of the unreinforced and jute-reinforced geomaterial. The test results demonstrate that including jute fibre in single, double, and triple layers increases the stiffness capacity of the soil at the optimum depth of D/4. The stiffness capacity at varied input parameters varies from 0.378 to 0.682 at the maximum penetration factor which shows an 80.42% enhancement of strength in pavement geomaterial. The outcome of the present study provides a cost-effective solution to the strength improvement in cohesionless soils for embankment, subgrade, and pavement construction technologies. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024.