Road Foundation Layer Research Articles

Analysis of Kinang Jingkion Material as Road Subbase Layer Using Soil Cement Method

This research aims to analyze the California Bearing Ratio (CBR) and Unconfined Compressive Strength Test (UCS) values as road foundation layers using local materials, namely Kinang Jingkion. The soil and Kinang Jingkion materials for the study were taken from the Apalapsili quarry in Yalimo Regency. Additionally, the additive or soil stabilizer used was matos obtained from the testing of soil characteristics, including sieve analysis or gradation, Standard Proctor Test for light density, and liquid limit test. After testing, it was found that the soil from the Apalapsili quarry is granular soil and can be categorized as A-1-a according to SNI 03-6797-2002. Subsequent testing involved CBR and UCS testing on Mix Designs made of soil and cement with concentrations of 4%, 6%, and 8%. Next, additional Mix Designs were created with compositions of Kinang Jingkion, soil, cement at 4%, 6%, and 8%. Further Mix Designs included compositions of Kinang Jingkion, soil, matos at 2%, and cement at 4%, 6%, and 8%. From the UCS testing results, Mix Designs with soil and cement concentrations of 4% and 6% did not meet the compressive strength criteria, with compressive strength values of 9.26 Kg/Cm² and 17.4 Kg/Cm² respectively. According to SNI 6887-2012, the compressive strength value after 7 days of immersion should be within 25-35 Kg/Cm², while other Mix Designs met the criteria of SNI 6887-2012. CBR testing also utilized the same Mix Designs, and the highest CBR result was obtained from the Mix Design with compositions of Kinang Jingkion, soil, cement at 8%, and matos at 2%, with a CBR value of 112%. According to the 2018 Revised General Specifications, a CBR value of 112% indicates a Class A Foundation Layer.

Analisis Kepadatan Lapangan Menggunakan Metoda Sand Cone Di Jalan Perumahan Ekajaya Permata 1 Sicincin Kota Payakumbuh

Every housing complex must have adequate road access because roads are a means of public transportation used by the community to support daily activities. Road infrastructure makes transportation easier and allows people to carry out activities. The road foundation layer will experience a decrease in the soil's bearing capacity as traffic flow increases, because the road structure distributes the load to all layers beneath it and supports the weight of vehicles passing on it. In circumstances like this, road construction must be of the utmost importance, and data about the existing soil on the site must be tested first. In this research, the author took a residential road that had just been built and still had a layer of compacted pavement. By making this road, people can more easily access transportation and feel comfortable when using it. Field density analysis was carried out on Jalan Perumahan Ekajaya Permata 1 Sicincin, Payakumbuh City. The sand cone method or sand cone test is used to calculate the degree of soil density. Various measurements are calculated, including sand bulk density, soil bulk density, water content, dry soil bulk density, and degree of field density. Tests were carried out at ten points at a distance of 25 meters each. The average soil water content is 7.73%. According to SNI 03-2008-1992, the recommended value of soil density is 95%. The test results show that the average degree of density in the field is 72.51%. Because the soil density in the field does not yet meet the soil density requirements of 95%, it is necessary to increase the compaction further until it meets the specified density requirements.

UTILIZATION OF SPENT BLEACHING EARTH WASTE ON LIME-SOIL STABILIZATION FOR ROAD BODY FOUNDATION LAYER BASED ON SOIL MECHANICAL

Soil stabilization is mixing soil with specific materials to improve the soil's technical attributes to meet specific technical requirements, such as increasing its stability. One stabilization method is chemical stabilization, which utilizes mixing heaped soil using lime and Spent Bleaching Earth (SBE). This research is focused on the effect of mixing lime with SBE for soil stabilization with maintenance time between 0, 7, and 14 days. The amount of lime used in the research is 4% from the soil dry weight with variations of the SBE mixture of 5%, 10%, 15%, and 20%. The conclusion obtained in this study was that adding SBE could increase the maximum dry density up to a percentage of 10%. Using SBE of more than 10% reduces the maximum dry density value but increases the optimum moisture content. From the mechanical attributes testing carried out, it can be seen that a percentage of 10% can increase the results of mechanical testing, while an increment above 10% will reduce the mechanical results. Based on the CBR and UCS test results, we found that lime and SBE mixture can pass the attributes limit for a grade S aggregate foundation layer and full-fill the requirement as a road body foundation layer. So, it can be concluded that lime and SBE mixture can be used as a road body foundation layer but has not reached the target for road foundation layers and requires maintenance for some time.

UTILIZATION OF SPENT BLEACHING EARTH WASTE IN SOIL-CEMENT STABILIZATION FOR ROAD FOUNDATION LAYERS IN TERMS OF THE MECHANICAL PROPERTIES OF SOIL

Various studies have been carried out to improve the parameters of soil mechanical properties. Efforts to improve the mechanical properties of the soil can be carried out in multiple ways, including automated means through compaction and chemical means through the addition of cement base materials. To improve the stability and properties of the subgrade soil, the cement base material that is commonly used is Portland Composite Cement (PCC). In several studies, apart from cement base materials, waste base materials have also been used for stabilization subgrade. This includes using bleached soil residues and rice husk ash as additives to stabilize the soil. The results showed that the use of soil bleaching waste in soil cement stabilization can be used to improve the mechanical properties of the embankment soil and the composition of the soil bleaching waste mixture so that mechanically, it is proven to provide the most effective improvement so that it can be used for road foundation layers made of cement soil. As part of this research, many tests can be carried out on normal and stabilized soils. Various percentages of SBE are 5%, 10%, 15%, 20%. PCC is introduced into the soil at a rate of 8% of the dry weight of the soil.

STUDY ON THE EFFECTS OF SOIL-CEMENT STABILIZATION IN THE LOWER ROAD FOUNDATION LAYER USING SPENT BLEACHING EARTH STABILIZER IN TERMS OF SOIL PHYSICAL PROPERTIES

In road construction planning, soil plays a primary role that will be examined. In geotechnical engineering, soil stabilization is one of the engineering sciences and efforts to enhance soil characteristics. Unbeknownst to many, ideas and concepts are generated to create new innovative materials that can replace or supplement existing materials. Based on this, the concept of utilizing spent bleaching earth (SBE) waste material emerged. With the advancement of engineering knowledge, particularly in the field of geotechnical engineering, soil stabilization is employed as an effort to improve soil characteristics. By utilizing SBE and cement as materials for soil stabilization in dams, the changes in the physical properties of the embankment soil before and after stabilization are examined. The physical property results are obtained through testing. Each obtained result is compared against the lower road foundation layer specifications based on the General Specifications for Road and Bridge Construction Works 2018 (Revision 2). Based on the testing and analysis, the plasticity index value with an optimum content of 10% and a curing time of 14 days, which is 7.576%, has met the requirements for constructing Class B roads' lower road foundation layer.

The Behavior of Dredged Soil-Shredded Rubber Embankment Stabilized with Natural Minerals as a Road Foundation Layer

Recently, geotechnical studies have been conducted more progressively to utilize dredged soil. The inclusion of shredded rubber (SR) and natural minerals (NM) to stabilize dredged soil (DS) has become an exciting issue in the geotechnical field. This technique can be a promising environmental innovation for the future. This study aimed to investigate the unconfined compressive strength (UCS), California bearing ratio (CBR), and embankment performance under the strip footing test. The UCS sample was prepared using shredded rubber with a proportion of 2% and 3% and natural minerals with a proportion of 3%, 6%, 9%, and 12% from the dry weight of the soil. Whereas for the CBR samples (both in un-soaked and soaked conditions) were also prepared with a proportion of 2% and 3% shredded rubber and 6% and 9% natural minerals from the dry weight of the soil as well. The strip footing test was conducted in small-scale laboratory tests to evaluate the performance of stabilized dredged soil embankments. The applied load test was gradually increased until the embankment collapsed. The results showed that adding shredded rubber and natural minerals could increase the UCS value by 3–4 times and the CBR value by 2–3 times. Furthermore, 84% and 116% efficient results were obtained in the strip footing test for the 7 and 14 days of curing, respectively. Therefore, the utilization of dredged soil stabilized with SR and NM can be considered for use as a road foundation layer. Doi: 10.28991/CEJ-2023-09-05-016 Full Text: PDF

CBR laboratory investigation on Lightweight Modular Block (LMB) using recycled dredged soil mixed with EPS

Changing material into a lightweight geomaterial such as EPSCS is one of the considerable methods to improve the geotechnical performance in the field. This material is already used in numerous construction projects due to its light characteristics. Lightweight Modular Block or LMB is a type of EPSCS composed of dredged Soil, cement, and Expanded Polystyrene (EPS). The amount of cement composition are 3%, 5%,7% and 9%. Meanwhile, Expanded Polystyrene (EPS) are 0.5% and 0.75%. This paper aims to briefly explain the performance of LMB as road foundation materials, such as subbase and base, through CBR laboratory tests. Based on the data, adding EPS can reduce density by 18% - 29% depending on the chosen mixture. Whereas adding more cement tends to increase the CBR value. All the test results will be analyzed and compared to SNI 03-3438-1994 for its qualification as a road foundation layer.

Foamed Bitumen Mixtures for Road Construction Made with 100% Waste Materials: A Laboratory Study

Nowadays, budget restrictions for road construction, management, and maintenance require innovative solutions to guarantee the user acceptable service levels respecting environmental requirements. Such goals can be achieved by the re-use of various waste materials at the end of their service life in the pavement structure, therefore avoiding their disposal in landfill. At the same time, significant savings are achieved on natural aggregate by replacing it with such waste materials, improving the economic and environmental sustainability of road constructions. The purpose of this study is to discuss a laboratory investigation about foamed bitumen-stabilized mixtures for road foundation layers, in which the aggregate structure was entirely made up of industrial by-products and civil wastes, namely metallurgical slags such as electric arc furnace (EAF) and ladle furnace (LF) slags, coal fly (CF) ash, bottom ash from municipal solid waste incineration (MSWI), glass waste (GW) and reclaimed asphalt pavement (RAP). Combining these recycled aggregates in different proportions, six foamed bitumen mixtures were produced and investigated in terms of indirect tensile strength, stiffness modulus, and fatigue resistance. The leaching test carried out on the waste materials considered did not show any toxicological issue and the best foamed bitumen mixture’s composition was characterized by 20% of EAF slags, 10% of LF slags, 20% of MSWI ash, 10% of CF ash, 20% of GW, and 20% of RAP. Its mechanical characterization presented a dry indirect tensile strength at 25 °C of 0.62 MPa (well above the Italian technical acceptance limits), a stiffness modulus at 25 °C equal to 6171 MPa, and a number of cycles to failure at 20 °C equal to 6989 for a stress level of 300 kPa.

Valorisation of dredged marine sediments for use as road material

The aim of this study is to investigate the suitability of using dredged marine sediments treated with a hydraulic binder in road construction works, particularly as a foundation layer. The methodology was conducted as follows. First, the geotechnical, chemical and mineralogical characteristics of the dredged sediments were determined to assess the behaviour of the materials. Second, the composition of the mixture was defined through a formulation study. In this phase of the study, the basic criteria for determining the dosage of each component of the mixture were specified. Third, the short-term and long-term mechanical behaviours of the formulation were evaluated. The experimental results show that dredged sediments treated with Portland cement can be used as a road foundation layer.

Analisis Gradasi Penggunaan Material Agregat Base Class A Spesifikasi BinaMarga 2010 Rev 3 Proyek Pelebaran Jalan Sp. Ujung Aji – Batas Kota Kabanjahe

Road is a land transportation infrastructure that covers all parts of the road, including complementary buildings and equipment intended for traffic. Road Structure Improvement is one project that aims to improve the quality of roads. As the object of work to be studied is the widening of the sp. Ujung Aji - Limits of the City of Kabanjahe. Road construction with a flexible layered pavement with cover or without overlays is usually often damaged such as: cracks, hollows, bumps on the road surface. In other conditions it is often seen that the grooves of the former water flow to the subgrade are visible. The situation is more extreme and often occurs, namely the road surface peels to reach the foundation layer, so that the aggregate looks scattered. This study uses the direct observation method in the widening project of Jalan Simpang Ujung Aji - Bts. Kabanjahe City. This research was carried out at the time of laying and compaction of the bottom road foundation layer such as Base B and Base A. Activities carried out included data collection, data processing, analysis and observations in the Laboratory. The results of the filter analysis of rough gradations are good, which is in the middle between the given gradation boundaries, does not coincide and does not come out of the given gradation limit. Based on aggregate filter analysis data, it can be concluded that the results of the gradation of aggregate class A percent are retained and passed the filter in accordance with the general specifications of Bina Marga 2010 revision 3 and according to class A aggregate planning. the specimen is completely waterless, so the weighing results in the right balance.

Environmental Impact Analysis of Low-Carbon Road-Foundation Layers

Emissions reduction and energy certifications of products are critical current issues. Both industry trends and the general public opinion are showing an increased concern about what is “sustainable,” “green,” or “energy-efficient”. Many processes and raw materials especially referring to industrial products have been analyzed to determine their environmental impacts, and “green certifications” and “eco-labels” are starting to be used by industries and companies, especially in Europe. This article presents a methodology designed to compute the carbon footprint of the stabilization of in situ soils with hydraulic binders and compares the results with the traditional supply of non-renewable resources used to build road foundation layers. The analysis is conducted by computing the emissions related to all processes (and equipment) involved in both in situ and traditional methods. A sensitivity analysis of the hauling distance of virgin aggregates (the most critical activity in the traditional process) assesses the influence of transportation activities on the entire construction process. The analysis shows that improving in situ soils through cement stabilization can save more than 80% in emissions if compared to the supply of traditional granular layers (assuming embodied energies are not considered). A “sustainable road pavement” should certainly consider the reuse of in situ soils to limit emissions during construction activities.

Brown Coal Fly Ash Concrete Mixture for Industrial Waste Containment

An experimental investigation on the feasibility of a sustainable method for the containment of contaminated sand and its reuse for the base and surface layer of a pavement is presented in this paper. The level of contamination of contaminated sand is determined and a fly ash based compound is added for the containment. The mix proportion for the base and surface layer of the pavement is selected based on the level of contamination. A mixture of fly ash based compound and the oil contaminated sand is tested for various properties such as strength, shrinkage, chloride resistance and leachability in this preliminary investigation, and is qualified for making road foundation layers.

Stabilization and Utilization of Dune Sand in Road Engineering

The aim of the work presented in this paper is the valorization of dune sand, which is abundant in Djelfa (Algeria). This study consists of valorizing a local material in road construction. Several stages were considered in this investigation. A method of formulation of the mixtures has been proposed, which is based on the stabilization of the studied sands using a hydraulic binder and a granular corrector. For each mixture, the optimum Proctor, the compressive strength with and without immersion and the tensile strength were determined. After that, an analysis of the results was made to examine the influence of the sand origin and the stabilization agent proportion on the physical and mechanical characteristics of mixtures. The stabilized sands were classified according to current standards; the optimal formulations were then selected, on which additional tests were carried out. The results obtained show that the formulations selected have sufficient performances to be used in road foundation layers.

Stabilized Dune Sand for Road Foundation Layers - Case of the Dune Sand of the Region of Djelfa (Algeria)

The aim of the work presented in this paper is the valorisation of dune sand, which is abundant in Djelfa (Algeria). This study consists of valorizing a local material in road foundation layers. Several stages will be considered in this investigation. A method of formulation of the mixtures has been proposed, which is based on the stabilization of the studied dune sand using a hydraulic binder and a granular corrector. For each mixture, the optimum Proctor, the compressive strength with and without immersion and the tensile strength have been determined. After that an analysis of the results was made in order to examine the influence of the stabilizing agent proportioning on the physical and mechanical characteristics of mixtures. A correlation between mechanical properties of the stabilized dune sand and the maximum dry density were proposed. The stabilized sand was classified according to current standards, the optimal formulation is then selected, on which additional tests were carried out. The results obtained show that the formulation selected has sufficient performances to be used in road foundation layers.

Microstructural Analysis for Mechanical Behavior of Granular Waste Materials

Many granular waste and recycling materials are being considered as substitutes for natural aggregates in construction applications. Incinerator bottom ash waste (IBAW), a residue from burning household waste, was previously landfilled, but now two-thirds of this ash is recycled, primarily in road construction. In this study, IBAW was mixed with limestone to produce a blend with acceptable properties for use as a road foundation layer. Cement was added to the blends to improve their mechanical characteristics. Scanning electron microscopy (SEM) was used to study the physical and chemical features of untreated and cement-treated IBAW blends and to identify the nature of the materials and any secondary reaction elements, especially after mixing with water. The micromechanical behavior of limestone–IBAW blends under uniaxial compression stresses was modeled on the basis of SEM images of the blends' microstructures. The results of micromodeling in general matched the experimental data very well. Microstructure modeling proved the high stiffness of the cement-treated blends. The material behavior in the plastic stage changed significantly with a change in the geometry and stiffness of the inclusions. Experimental and modeling results also showed that IBAW material behaved as a conventional aggregate. Results demonstrated in general that microstructural analysis was quite useful in describing the mechanical behavior of IBAW and could be applied to all granular waste materials.

Effectiveness of novel and traditional treatments on the performance of incinerator bottom ash waste

Management of natural aggregate resources has become one of the most important challenges in construction, especially for high demand applications such as roads. Incinerator bottom ash (IBA), which is produced from burning domestic waste, has been considered a useful solution to the shortage of natural resources. In this research, IBA was mixed with limestone to produce an acceptable blend for use as a road foundation layer. Novel and traditional additives were adopted to improve the mechanical properties of IBA blends. The study focused on the treatment effect of additives on the mechanical characteristics of IBA blends under monotonic and cyclic triaxial stresses. The investigation evaluated fundamental material properties, including resilient modulus, initial Young’s modulus and Poisson’s ratio. Two nonlinear empirical models were adopted to depict the experimental resilient modulus results of the IBA blends. An approach has been proposed to predict realistic and representative values of resilient modulus for the material. In addition, a new relationship has been established between Young’s modulus, resilient modulus and Poisson’s ratio. Triaxial test results revealed that additives are more efficient with the control limestone blend than with the IBA blends. Novel additives, such as enzyme I and silica fume, produced a noticeable improvement in IBA properties in comparison to traditional additives.

Quantification of the properties of enzyme treated and untreated incinerator bottom ash waste used as road foundation

A substantial amount of incinerator bottom ash (IBA) waste is generated annually from burning municipal solid waste. IBA is similar to aggregate consisting of ferric metals, non-ferrous metals, brick and tile fragments, ceramic, glass, stone, dirt, etc. In this work, IBA waste was mixed with conventional limestone aggregate in an attempt to achieve a blend with acceptable mechanical properties and minimum environmental risks for use in road foundation layers. Enzyme treatment was applied in order to improve the behaviour of IBA–limestone blends. A series of laboratory tests, such as cyclic triaxial compression tests, pH monitoring and scanning electron microscope, were adopted to determine the materials' mechanistic behaviour and microstructure characteristics. Emphasis was on examining the effect of various parameters, such as IBA content, enzyme content, moisture content and curing time. Results of this study showed that IBA blends gave a favourable performance as road foundation layers in comparison with the control limestone blend. Microstructure and chemical analysis results showed that the addition of plant-based enzyme improved the mechanical properties of the control limestone blend; however, it did not have any noticeable effect on the IBA blends.

Experimental and Numerical Evaluation of Stabilization Effect on Pollutant Mobility from Incinerator Bottom Ash Waste

Before incinerator bottom ash waste (IBAW) is used as a construction material, its environmental impacts should be thoroughly investigated. IBAW encompasses ferrous and nonferrous constituents that, in the presence of water, might be released into the groundwater and soil. The aim of this study was to find a treatment technique to improve the quality of IBAW and to reduce, to below regulatory limits, its potential to leach metals and salts. IBAW was mixed with limestone to achieve an environmentally and functionally acceptable blend to be used as a road foundation layer. The research studied the leaching characteristics of some constituents—including sulfate, chloride, sodium, copper, zinc, and lead—in IBAW blends under different conditions, such as initial pH value and the use of novel and traditional treatment agents. The experimental program was designed to recreate a realistic environment; a lysimeter was used as a large-scale leaching tool and a laboratory protocol was developed that simulated road foundation field conditions to evaluate the long-term release of heavy metals and salts from IBAW. In the lysimeter experiments, the concentrations of the leached elements were monitored through a sand substrate underneath the IBAW layer to study the potential element migration and sorption process. Mathematical modeling was then used to simulate the release of the aforementioned constituents from the IBAW on the basis of the initial measurement of intrinsic material properties and the sorption process concept. The experimental results showed that the additive treatment had a varied impact on the IBAW blends’ leaching properties, as element release was reduced by a wide margin, ranging from 5% to 96%.

Backcalculation Models to Evaluate Light Falling Weight Deflectometer Moduli of Road Foundation Layer Made with Bottom Ash Waste

Incinerator bottom ash (IBA) is a residue from burning household waste that once was put into landfills. Nearly two-thirds of this ash is reused, primarily in road construction. In this study, IBA was mixed with limestone to produce a blend with acceptable properties for use as a road foundation layer. In situ simulative testing with a light falling weight deflectometer (LFWD) and subsequent interpretation of the surface deflection data have enabled evaluation of the mechanical properties of the foundation and subgrade layers. An experimental and modeling study of the elastic dynamic response of a foundation layer of IBA waste and limestone that was subjected to LFWD impact loading is presented. Several parameters—such as IBA content, water content, and curing time—were studied. Regression, mathematical, and three-dimensional finite element models were developed to backcalculate the LFWD moduli of the foundation layers. The modeling approach accounted for the static and impact nature of the LFWD load. Results showed that IBA blends underwent less deflection, as a foundation layer, than the control limestone blend. Backcalculated modulus results based on the dynamic effect of the LFWD load produced different values from those calculated by Boussinesq's equation, which is adopted by the LFWD manufacturer.

A philosophy for a performance specification for road foundations

The road foundation layers perform several functions both during construction and when the road is in service, for example load-spreading, temporary haul routes, and a base for the overlying construction layers. The critical loading condition is usually directing trafficking where the applied stresses are greatest. The capping and sub-base layers during construction require adequate stiffness and strength to resist these stresses. The current UK specification for road foundations is based on a recipe approach, and, unless permission is granted to use an analytical design, the pavement foundation designs are based entirely on the California Bearing Ratio (CBR) to characterise the subgrade, capping and sub-base materials. Here CBR is used as an index of both material strength and stiffness, although it measures neither directly. Such an approach is potentially inefficient and does not readily facilitate the use of new and marginal materials or alternative design procedures. Recent technical advances in laboratory and in situ testing of pavement foundation materials now allow the performance parameters of stiffness, strength and resistance to permanent deformation to be measured both for design and during construction. This in turn enables a performance-based specification for road foundation layers to be introduced to provide some assurance of the as-constructed quality, and by permitting the use of secondary or recycled aggregates, to contribute to the parallel goal of sustainable construction. This paper sets out an idealised philosophy for a performance-based specification for road foundations, examines the individual elements of the specification in relation to current knowledge and makes recommendations for a phased introduction alongside CBR-based methods.