These are mainly due to an increase in the number of vehicles, especially those with high axle loads, but also the effects of the environment, as well as errors made during construction and design. The life of the road surface is shortened as a direct result of the severe deterioration caused by the overweight trucks. The aim of this study is to compare the mechanical properties of the wear course used by JKR & LLM, as well as the Marshall Stability and the conditions of the paving material, in order to estimate the tensile stresses occurring under the asphalt. concrete layer (AC) and the compressive stresses that occur above the subsoil surface.
Base thickness and subgrade elastic modulus were the main factors that determined the balance between pavement abrasion and fatigue life. Secondly, I would like to express my appreciation to everyone who directly contributed to my FYP. Muslich Hartadi Sutanto, for taking me under his wing and helping me through my FYP experience.
Montasir Osman Ahmed Ali, for helping me throughout the course by giving me frequent updates on the course and supplementary lectures so that I could better understand how to complete my FYP. I will never forget how hard they worked to help me complete my experiments and I am truly grateful for the time and effort they invested in me to complete my FYP.
- Background of study
- Problem Statement
- Aim and Objectives
- Scope and Limitations of the Research
- Novelty of Research
- a
- Background Study of Asphalt Concrete
- Flexible Pavement in Malaysia
- Hot Mix Asphalt (HMA)
- Fatigue Failure on Asphalt Pavement
- Rutting in Pavement
- Stiffness of Pavement
- Wearing Course Used by JKR and LLM Specifications
- Marshall Stability and Flows for JKR and LLM Specification
The properties of the asphalt binder used have the most significant influence on the mechanical properties that an asphalt mixture possesses. The dynamic impact test and the fatigue life of a particular asphalt mixture are both used in the process of determining the deformation characteristics of the asphalt. The reduction in cohesive force can be attributed to the softening of the asphalt concrete mastic.
Due to the fact that both mechanisms are interrelated, a moisture-damaged pavement may be the result of a combination of both mechanisms (Nejad et al., 2012). Rutting is the term used to describe the permanent deformation of pavement that can occur when heavy traffic is driven over soft asphalt pavement. There will be a greater range of sizes present in the mix if the maximum aggregate particle size that can be used is increased.
Uncompacted material increases permeability problems and oxidative aging of the binder, reducing the life of the pavement (Gudimettla et al., 2003). The stress-strain diagram of a material shows its stiffness, which is one of the characteristics of the asphalt mix in terms of strength and durability. The Marshall Stability Index is a measure of the maximum load the samples can carry.
The amount of test load to be carried increases until it reaches a maximum value.
- Introduction
- Materials
- Marshall Stability Test
- Indirect Tensile Strength Test
According to the predefined gradation of the Malaysian Ministry of Public Works (PWD), the aggregate gradation ACW(AC14) was chosen for a wear layer intended for heavy traffic. The aggregate used in the research was subjected to sieve analyses, and the results of these analyzes are shown in Table 2.6 below. After placing a piece of filter paper in the bottom of the mold, the mixture was then added to the mold.
Finally, the outline of the mold was scraped with a heated spatula to smooth it out. After removing the collar, the surface of the mixture was troweled into a slightly rounder shape. The temperature of the mixture was kept at 150 degrees Celsius until the moment before compaction.
After the ring was replaced, the mold assembly was placed on a press stand inside the mold holder, and 75 blows were then applied to the top of the sample. After removing the base plate and collar, the pattern was turned upside down and the mold was then reassembled. After the pressing process was completed, the base plate was removed and the mold containing the sample was immersed in cold water for two minutes.
In order to accurately read the density of the sample, it was weighed in air and sterile water at room temperature. The inner surfaces of the test heads and guide rods were thoroughly cleaned. The sample sitting in the water bath was transferred to the lower part of the refracting head.
After this step, the upper part of the breaking head was mounted on the specimen, and the entire assembly was then placed appropriately on the test apparatus. While the load was being applied, the flowmeter was maneuvered into position so that it would rest on top of the guide rods, and the sleeve was pressed firmly against the most elevated portion of the breaker head. During the course of the test, the amount of time that elapsed between the removal of the sample from the water bath and the determination of the maximum charge did not exceed thirty seconds.
- Introduction
- Marshall Properties
- Marshall Stability and Flows
- Optimum Bitumen Content
- OBC for ACWC 14
- OBC for ACWC 20
- Indirect Tensile Strength
When it comes to the quality of bitumen to be placed and compacted, one of the most important control parameters to consider is the air void content of bituminous materials (Harvey & Tsai, 1996). Air voids are designed to make room for binder expansion in summer and also for compression (Kandhal et al., 1998). During the load test, a gauge button is attached so that the plastic flow of the specimen can be measured in response to the applied load.
The current value is used to indicate that the vertical deformation of the sample is 0.25 mm (measured from the start of the load to the point where the stability of the sample begins to decline). Low flow rates may indicate a mix with more than normal voids and insufficient asphalt for durability, as well as a mix that may exhibit premature cracking due to brittleness of the mix during the life of the pavement. The ideal bitumen concentration is 5.56 percent, according to the calculation done with the previous value.
Findings show that stability improves with increasing bitumen content up to the point where it reaches its optimum level, after which it starts to deteriorate again (Chen et al., 2009). It was found from the grading of JKR and LLM that the mixture containing different sizes of aggregate and filler had a degree of stability that was slightly higher than the mixture. According to the findings, the asphalt mixture for ACWC14 has greater stability than ACWC20.
Looking at the results, it is clear that the flow increases as the amount of bitumen in the mixture increases. The flow value of the mixture was 4.26 millimeters for ACWC20 and 4.05 millimeters for ACWC14 when the optimum binder content was 5.5%. The percentage of voids in the total mixture is plotted against the amount of bitumen in Figure 4.2.2.
Although ACWC14 has a higher air voids than ACWC20, the lower voids in the mixture can be attributed to the improved bond obtained due to asphalt surface modification and the stiffening effect. As can be seen in Figure 4.2.2, the bulk density increases as the amount of bitumen in the mixture does as well. The primary objective of the current research is to investigate the effect of filler material and test temperature on the tensile properties and moisture absorption of bituminous concrete mix prepared with stone dust and cement as filler material.
The dry strength of the sample was evaluated using a total of 6 samples: 3 samples for ACWC 14 and 3 samples for ACWC 20. Temperature is one of the factors affecting the tensile strength of samples, with the tensile strength increasing with decreasing temperature to a maximum value that is more or less the same for all asphalts in newly constructed roads at low temperatures.
Conclusion
The tensile strength test cannot distinguish between adhesion and cohesion qualities, but is used to evaluate the quality of different bitumen products. This has shown that LLM is using the high quality asphalt pavement and standardized AC20 to build most of the highway in Malaysia.
Recommendation
Evaluation of marshall properties of asphalt mixtures with aggregate gradations designed by the bailey method Universiti Teknologi Malaysia]. Evaluation of asphalt mixtures incorporating electric arc furnace steel slag and copper mine tailings for road construction. Effect of Bitumen Grade on Hot Mix Asphalt Properties Prepared Using Recycled Coarse Concrete Aggregate.
Evaluation of Marshall properties of Acw 14 using river sand and carbide lime as filler Subjected to 75 numbers of compaction Universiti Malaysia Sarawak]. Traffic channelization and pavement rutting: an investigation of the role of lateral wandering on asphalt pavement rutting.
