Available online at www.sciencedirect.com ScienceDirect Materials Today: Proceedings 18 (2019) 2270–2278 www.materialstoday.com/proceedings 2214-7853 © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 ICMPC-2019 Performance Of Concrete At Elevated Temperatures Made With Crushed Rock Dust As Filler Material N.Venkata Sairam Kumar a, * , K.S.Sai Ram b a,b Department of Civil Engineering, R.V.R & J.C. College of Engineering, Guntur, Andhra Pradesh, India. * Research Scholar, Acharya Nagarjuna University, Guntur, Andhra Pradesh, India. Abstract This experimental study presents the effect of partial replacement of cement by crushed rock dust (CRD) as filler material in concrete when subjected to elevated temperatures. Ordinary Portland cement (OPC) is partially replaced with CRD in five percentages: 0%-control concrete: (CC), 10% (CR1), 20% (CR2), 30% (CR3) and 40% (CR4)) by weight. The CC and CRD concrete specimens were subjected to elevated temperatures of 200 o C to 800 o C for 2 hours using an electrically controlled furnace. Ultrasonic pulse velocity (UPV), Mass loss, compressive strength, surface cracking and colour change are evaluated at elevated temperatures. Additionally, the micro-structural properties of CC and CRD concrete at ambient and at elevated temperatures is analyzed using scanning electron microscope (SEM). At ambient temperature, the test results of concrete with CRD up to 30% showed enhanced UPV and compressive strength values than CC. No visible cracks are observed on CC and CRD concrete surface exposed up to 400 o C. UPV values obtained at elevated temperatures with CC and CRD concretes are in good agreement with mass loss and compressive strength values. The results signify that the partial replacement of cement up to 20% with CRD showed the best performance than CC at elevated temperatures and are supported by SEM analysis. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 Keywords: Concrete; Micro-structure; Crushed rock dust; Mass loss; Compressive strength; Ultrasonic pulse velocity. * Corresponding author. Tel.: +91 949 324 3087; E-mail address: sairam852@gmail.com.