Conference Papers

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

Browse

Search Results

Now showing 1 - 2 of 2
  • Item
    Laboratory Performance of Superpave Mixes for Perpetual Pavements
    (American Society of Civil Engineers (ASCE), 2017) Priyanka, B.A.; Goutham, G.; Lekha, B.M.; Ravi Shankar, A.U.
    Long life asphalt pavement, also known as "Perpetual Pavement", is a pavement with design life more than 50 years and needs only periodic surface renewal. It works on the concept of controlling horizontal tensile strain at the bottom of the asphalt layer and vertical compressive strain at the top of the subgrade to a particular limit. This can be achieved by increasing the binder content of the mix over the optimum binder content (OBC) and by increasing the overall pavement thickness. In the present study two Superpave mixes were prepared using conventional binder at OBC (optimum binder mixture [OBM]) and also at 0.5 % extra binder over OBC (rich binder mixture [RBM]) which can be used in Perpetual Pavements. The mixes were tested for indirect tensile (IDT) strength, moisture susceptibility, fatigue and rutting resistance. From the results it was observed that, OBM performed well as compared to RBM. However the fatigue life of RBM was more compared to the OBM and this helps in reducing the horizontal tensile strain at the bottom of the asphalt layer which in turn increases the life of the pavement. © ASCE.
  • Item
    Experimental Studies on Lateritic Soil Stabilized with Cement, Coir and Aggregate
    (Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2021) Ravi Shankar, A.U.R.; Priyanka, B.A.; Avinash
    The characteristics of subgrade soil play a vital role in designing the pavement structure so that the pavement has required support from the bottom layer. During adverse weather conditions and higher traffic loads moving on any pavement, it should be able to withstand the impact and perform well for longer duration. Load is transmitted from pavement to the subgrade layer and distributed evenly through the soil particles. All types of soil are not capable of handling such impacts by their own and needs additional stabilization processes. Several stabilization processes are available in which the best one has to be taken into consideration. Fibers such as coconut coir are important in giving extra stability to the soil particles. Cement is well-known material in construction sector along with aggregates. Lateritic soil is available abundantly in coastal areas of southern parts of India which has porous structure and demands stabilization when the intended purpose is specific and requires higher strength and durability. In this study, coconut coir along with cement and aggregate are taken as stabilization materials to stabilize lateritic soil. Initially, basic properties of soil like plastic limit, liquid limit and plasticity index are determined. Grain size analysis is done and modified Proctor test is conducted to determine the optimum moisture content (OMC) and maximum dry density (MDD) of the soil. Unconfined compression test (UCS), California bearing ratio test (CBR), flexural fatigue analysis, durability properties with respect to wet-dry cycles and freeze–thaw cycles are evaluated for untreated and treated soil specimen. As per UCS values, cement can be taken at an optimum dosage of 6%. The coir fibers from natural husk of coconut and aggregates of 10 mm below size were added to the soil–cement mixes and an optimum dosage of coir and aggregate is determined. The study showed positive results in terms of CBR values of cement-aggregate treated soil. © 2021, Springer Nature Singapore Pte Ltd.