Design of a bituminous mixture for perpetual pavement

[摘要] The flexible pavements with a design period of 50 years without requiring major structural rehabilitation and reconstructions are called as perpetual pavements. The present study aims at designing a high modulus Dense Bituminous Macadam (DBM) mixture for perpetual pavements using Industrial Grade (IG) bitumen in combination with Viscosity Grade (VG30) bitumen. Various blending combinations were tried and the ratio of 70:30 for IG: VG30 was found to fulfill the requirements. The modified Marshall hammer was used for the preparation of specimens, as the nominal size of aggregate was 25 mm. A comparative study on DBM mixture with VG30 alone and with IG: VG30 (70:30) was done and the Optimum Binder Contents obtained were 5.0 % and 5.3 % respectively at 4 % air voids. The water sensitivity tests were carried out on the bituminous specimens in accordance with AASHTO T 283 and the Indirect Tensile Strength (ITS) ratio obtained were 80.0 % and 98.3 % respectively for specimens with VG30 and IG: VG30. The stiffness modulus of DBM specimens with IG: VG30 bitumen was 3 times higher than DBM with VG30 bitumen.

[发布机构] Dept. of Civil Engineering, BITS Pilani Hyderabad Campus, Jawahar-nagar, Shameerpet, Hyderabad, Telangana; 500078, India^1

[效力级别] 机械制造

[关键词] Bituminous mixtures;Comparative studies;Flexible pavements;Indirect tensile strength;Industrial grades;Perpetual pavements;Structural rehabilitation;Water sensitivity