Highway Research Record

II. PAVEMENT ENGINEERING AND PAVING MATERIALS
2. FLEXIBLE PAVEMENT
ON GOING PROJECTS
Field Studies on Use of NRMB and CRMB in Bituminous Surfacings under Different Climatic Conditions

Date of Start: December 2003
Central Road Research Institute, New Delhi (R, I)

Present Status & Progress

Characterisation of NRMB-40 and NRMB-70 have been completed as per IS -15462. Construction sites for field trials were identified at NH-44 (km 126 and km 127), NH-1A (km 114, near Jawahar Tunnel) and Suratgarh Byepass. Construction of experimental test sections using 60/70 bitumen, CRMB-40 and NRMB-70 have been completed at km 126 and km 127 of NH-44. The first 6 monthly observation at NH-44 (Meghalaya) have been completed. Further works are in progress.

Findings/Conclusions
NRMB and CRMB mixes showed improved Marshall Quotient of SDBC. Failure temperature of modified mixes is 8-100C higher than conventional 60/70 bitumen. Performance of NRMB section was slightly better than 60/70 bitumen in high rainfall area.