Abstract

The use of waste recycled materials in road construction nowadays is considered a positive means of providing improved pavement performance. This research focused on evaluating the effect of waste glass powder as a partial replacement of crushed stone dust filler in hot mix asphalt. Three hot mix asphalt samples were produced using crushed stone dust of 5%, 6.5%, and 8% as mineral filler with five different bitumen content of 4%, 4.5%, 5%, 5.5%, and 6%, respectively. From the preliminary series tests of asphalt contents, a 6.5% crushed stone dust filler selected, providing the highest waste glass powder stability. The content of crushed stone dust filler was replaced with a rate of 0%, 25%, 50%, 75%, and 100% to test Marshal stability to obtain the Optimum bitumen content and Optimum filler content. Results indicated at 75% replacement of crushed stone dust with waste glass powder at 5.10% bitumen content, 12.0kN Marshall stability value, 2.84mm Flow value, 4.0% Air voids, 72.3% VFB, and 2.360g/cm3 Bulk density. Hence, the mixture of 75% waste glass powder by weight of crushed stone dust filler meets the minimum requirements of the Ethiopian Road Authority and Asphalt Institute Specifications.

Abstract

A bituminous paving mixture is a mixture of coarse aggregate, fine aggregate, and bitumen mixed in suitable proportion to result in a strong and durable mix in order to withstand traffic load. In this paving mix, ordinary stone dust, and cement used as filler material. One of the main problems in the construction of a bituminous paving mixture is the insufficient amount of filler from crushing stone aggregate, and cement supply is low. A study has been carried out in this research to explore the use of Brick dust as filler material for the bituminous mixture. The objective is intended to evaluate the performance of brick dust as fillers in Hot Asphalt Mix design, according to the test procedure specified by ASTM. Several specimens of hot asphalt mixture were prepared according to ASTM D 1559 using an aggregate blend with brick filler and aggregate blend without brick filler. The aggregate blending made by using Job mix formula to obtain the percentage of mixed material. For aggregate blended without brick G-1 32%, G-2 23%, and G-3 45% for Aggregate blended with brick filler G-1 30%, G-2 18%, G-3 45% and G-4 7%; where G-1 Coarse Aggregate 3/4, G-2 Coarse Aggregate 3/8, G-3 Fine Aggregate, and G-4 brick filler. It concluded that the results of the Marshall test of mix design showed satisfactory when hot asphalt mixed with these brick fillers. The Specimens blended with brick filler lead produce asphalt mixture with higher Marshall stability, lower flow, a less void filled with asphalt. Hence, brick dust can replace stone dust and cement filler in the bituminous paving mix. It is recommended to use brick dust as filler material in a bituminous paving mix may save considerable investment; as well as a reliable performance of the in-service highway can be achieved.

Abstract

During the fabrication of new products, a variety of wastes discharged and stored by causing harsh environmental problems. The marble processing plant is amongst the industrial sector that produces huge waste. Thus, the main purpose of this study is to evaluate the combined effects of marble waste dust filler and Superpave aggregate gradation on the performance of HMA. Based on the Marshall Mix design, seventy-two (72) specimens were produced from three below-restricted zones (BRZ) of Superpave gradation (BRZ4, BRZ5, & BRZ6) by using the 0.45 power chart. The design gradation obtained to be BRZ5 with 4.96% OBC with corresponding values 9.13 KN of stability, 2.96 mm of flow, 73.51% of VFA, 15.73% of VMA, 2.308 gm/cm3, of bulk density, and 4% of air void. The crushed stone dust filler was partially replaced by Marble Waste Dust filler (under No. 200 sieve) at a replacement rate of (1%, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5%) by keeping design gradation and OBC constant. The test showed satisfactory results. The Marshall mix design parameters of all mixtures are within the specification limit under international and local specifications. Marble waste dust filler when blended with a BRZ of Superpave gradation indicated a substantial effect on Marshall stability with 10.18 KN value at 3% MWD filler content.