International Journal of Scientific Engineering and Science Volume 7, Issue 7, pp. 12-16, 2023 ISSN (Online): 2456-7361 12 http://ijses.com/ All rights reserved Index Retained Strength Mixture of Fine Stone Mastic Asphalt using Concrete Waste Aggregate Rais Rachman Associate Professor, Department of Civil Engineering, Universitas Kristen Indonesia Paulus, Makassar, 90241, Indonesia Abstract— Concrete waste that is left untreated will cause its own problems for the environment. The purpose of this study is to analyze the Retained Strength Index for Stone Mastic Asphalt mixtures that use concrete construction demolition waste aggregate. The test method used is the Marshall method. Aggregate test results from waste concrete meet the requirements for use as a fine SMA material. This can be seen from the results of the aggregate resistance test and the specific gravity obtained. The results of the Stability and Flow tests as well as the VIM and VMA analysis show that the values meet the Bina Marga standards. The results of the Marshall Immersion test show that the Retained Strength Index Value is 92.71%. Based on these values, it can be concluded that road pavements using concrete waste aggregate in a mixture of fine Stone Matrix Asphalt (SMA) can withstand temperature and the length of time they are submerged in water. Keywords— Concrete waste, Marshall Method, Index Retained Strength. I. INTRODUCTION Limited natural resources in providing concrete-forming materials is an important issue. The existence of several old buildings that are no longer used must be demolished because these buildings need to be renewed, are damaged, or are no longer fit for habitation. On the other hand, the demolition of buildings and civil infrastructure consisting of concrete materials creates concrete waste. Concrete waste that is left untreated will cause its own problems for the environment. Disposal of waste requires a fee and a landfill. Currently ready mix concrete is being widely used for the manufacture of building construction, however, in its application, excess supply often occurs and the remainder is sometimes disposed of in any place, which can cause new problems. With all the advantages that can be observed from various recent studies, the reuse of concrete waste in the form of fractions as a substitute for coarse aggregate deserves research because besides being cheap and environmentally friendly, it is also expected to be able to provide satisfactory results. Stone mastic Asphalt (SMA), which is a type of hot asphalt mixture consisting of coarse aggregate, fine aggregate, and filler and adhesive in the form of rich asphalt binder mortar and has contact between the coarse aggregate to form a rock framework known as Stone-on stone skeleton. contact for load distribution [1] [2]. SMA is used as a road pavement surface layer with Open graded aggregate composition or it can also be called a uniform gradation which means it only contains a small amount of fine aggregate so that there are many voids or empty spaces between the aggregates. On the surface layer there is a wear layer and an intermediate layer, where the Asphalt Stone matrix as the wear layer lies above the intermediate layer [3] To analyze the Retained Strength Index, a material characteristic test is needed in the form of aggregate characteristics, asphalt characteristics and filler characteristics used [4] [5]. In addition, the characteristics of the mixture through the Marshall Conventional and Marshall Immertion tests [6]. Research that has been done under the title Utilization of Recycled Concrete Aggregates in Stone Mastic Asphalt Mixtures [7]. Use of Waste Concrete as Aggregate in Fine Asphalt Stone Mastic Mixture [8]. Laboratory evaluation of treated recycled concrete aggregate in asphalt mixtures [9]. Behavior of a hot mix asphalt made with recycled concrete aggregate and crumb rubber [10]. The purpose of this study is to analyze the Retained Strength Index for Stone Mastic Asphalt mixtures that use concrete construction demolition waste aggregate. The specifications used are the specifications that apply in Indonesia, namely Road and Bridge Work Specifications [11]. II. METHODOLOGY A. Materials The research was conducted in a laboratory at the Road Pavement Laboratory of the Civil Department, Paulus Indonesian Christian University. The aggregate used is building demolition waste from various locations in Makassar City, South Sulawesi Province, Indonesia (Figure 1). The asphalt used is Pen 60/70 with an asphalt content of 6.00% for each mixture; 6.25%; 6.50%; 6.75% and 7.00% by weight of the mixture. While the filler used is Portland Cement. Fig.1. Concrete waste B. Mixture Composition and Test Objects Determination of the composition of the mixture is based on the results of the analysis of the mixture gradation. The results of the analysis can be seen in Table 1. While the number of samples used was 5 for each bitumen content and a total of 25 samples for the Conventional Marshal test and 5 samples for Marshall Immersion.