Road Construction Materials Research Articles

The impact of the ecological and climatic characteristics of the territory on the condition of the housing stock

The problem of environmental pollution is relevant at the present time. Any enterprise is a potential source of environmental pollution, and the production of road construction materials is one of the enterprises that pose a significant danger to the environment. As an example, we chose Primasfalt LLC, which is one of the main enterprises serving the roads of the city of Vladivostok. At all stages of the preparation of asphalt concrete mixtures, pollutants are released. Toxic substances accumulate in the atmospheric air, then fall on the ground in the form of liquid and solid precipitation, penetrating into the soil, groundwater is polluted, and the balance of nutrients in the soil is disturbed. In the course of the study, an assessment was made of the impact of asphalt concrete production on the condition of soils through the use of test objects — living organisms that are able to respond to environmental changes. The test object was oats, the most common and widely available bioindicator of soil conditions. Sampling points are located within the sanitary protection zone of the enterprise. When sampling, the climatic characteristics of the city of Vladivostok were taken into account. The results of the study showed that high toxicity of soils is observed at points located in the zone of maximum values of wind speed and its frequency. With the help of bioindicator organisms, it is possible to quickly and inexpensively analyze the state of the natural environment. Assessing the activity of an asphalt concrete plant with the help of biological objects makes it possible to identify the intensity of its impact not only within the framework of normative values that are aimed specifically at humans, but also at biological objects in general, which determines the relevance of the chosen topic. The purpose of the study is to assess the level of soil toxicity within the regulatory sanitary protection zone of the LLC Primasfalt enterprise in the city of Vladivostok, Primorsky Krai.

Enhancement of kaolin clay soil for civil engineering application using rice husk ash and sawdust ash geopolymer cements

These days, good quality road construction materials are scarce and their haulage to the construction site is expensive. When unsuitable materials are encountered during flexible pavement construction, the most technical and economical option is always to improve them to meet design standards. One of these deficient materials mostly encountered in tropical regions is kaolin clay soils. Cement and lime that are traditional deficient soil improvement agents are on high demand therefore have kept the cost of engineering construction financially high. Thus, the use of agricultural wastes such as sawdust and rice husk as alternative construction materials will considerably reduce the cost of construction and as well mitigate the environmental hazards caused by the wastes and cement production. This study investigated and compared the performance of rice husk ash (RHA) and sawdust ash (SDA) geopolymer cements in improving the geotechnical properties of kaolin clay soil used for flexible pavement construction. All laboratory experimental tests were carried out in accordance with British Standard (BS) 1377 and BS 1924 for natural and modified kaolin clay soil samples respectively. Soil samples were mixed with geopolymer cement at stepped concentrations of 0, 4, 8, 12, 16 and 20% by dry weight of soil. Results indicated that the plasticity index value of the natural kaolin clay of 18.52% was reduced to 7.24% at 20% RHA geopolymer cement content. The unconfined compressive strength of the natural soil was improved by 600 and 400 % by RHA and SDA geopolymer cements respectively. It was concluded that the use of up to 20% RHA and SDA geopolymer cements can efficiently and eco-friendly improve kaolin clay for flexible pavement foundation purpose.

RECOMMENDED STUDY OF EXTINGUISHING METHODS BASED ON THE 1994 PETTIFER AND FOOKES CRITERIA APPROACH TO THE PLANNING OF THE TRANS-PAPUA WASIOR-NABIRE ROAD

The road is one of the traffic infrastructures for driving which supports all community activities. One of the stages of road construction is land clearing, in which one of the activities is eviction or excavation. The road construction location is the Trans Papua Wasior-Nabire road, Yamor District, Kaimana Regency, West Papua Province. However, the problem in this study is whether the excavation method is suitable for excavating material for road construction. Based on these problems, the purpose of this study is to recommend a method of excavation on the Trans Papua Wasior-Nabire road section. The method used is the Pettifer and Fookes (1994) criterion approach to determine the capability method. The results obtained with this approach indicate that the KM 501+500 excavation site is included in the level of easy digging capability or enters into a condition that is easy to dig. At the KM 502+100 excavation site, it is included in the hard digging capability level or a category that is difficult to dig because of the condition of the material which is difficult to dig, so the recommendation given is to use heavy equipment, namely a hydraulic excavator (backhoe) or a power shovel.

Structural and Mechanical Properties of Modified Hot and Warm Mix Asphalt Concrete

Statement of the problem. The problem of improving the structural and mechanical properties of hot and warm mix asphalt concrete based on mineral materials, produced by Ltd. «PavlovskNerud», Voronezh region, is considered, using the method of polymer-dispersed reinforcement. The effect of the modifier RTEP-M on the resistance of rutting for hot and warm mix asphalt concrete has been studied. Results. By studying hot and warm mixes asphalt with RTEP-M modifier in the amount of 0.3 and 0.6 % by weight in the mineral part, respectively, and the control composition, a significant improvement in structural and mechanical properties was achieved. It is shown that it is possible to increase the resistance of rutting for hot and warm asphalt concrete prepared on local road construction materials by increasing its viscous-elastic properties by using the method of dispersed reinforcement using the Russian additive RTEP-M. Conclusions. The efficiency of using the method of polymer-dispersed reinforcement to improve the structural and mechanical properties of hot and warm asphalt concrete based on local mineral materials has been proven. It is shown that the addition of the RTEP-M modifier to the mineral part of hot and warm asphalt concrete mix in the amount of 0.3 and 0.6 % by weight, respectively, improves the rutting resistance of the road surface. It has been proved that by applying the method of polymer-dispersed reinforcement, it is possible to optimize the properties of warm asphalt concrete for its use in hot climatic conditions for the introduction of warm technologies instead of hot ones in the construction and repair of road surfaces.

Measurements of Terrestrial Gamma Dose Rate Distributions along Idiroko Road, Ota, Ogun State, Nigeria: Health Implications on Roadside Dwellers

An extensive study concerning the terrestrial gamma dose rates of the surface soils from Canaanland entrance Road, Ota to Eleha Complex along Idiroko Road, Ota has been carried out to cover the road running across both areas. The In-situ measurements of gamma dose rates and radionuclides were carried out using the Gamma detector (Super Spec RS 125). The result shows that the average outdoor gamma dose rate in the study area is 73.57 nGyh−1. The average values of the radionuclides obtained were 32.9 Bq/kg for 238U, 68.4 Bq/kg for 232Th, and 328.7 Bq/kg for 40K. The background dose rate of 113.3 nGy/h was found in station 9 and is twice higher than the recommended permissible limit of 59 nGy/h suggested by UNCSEAR, 2000, and ICRP, 1999, respectively. Results were obtained based on radiological parameters for the outdoor absorbed dose rate (Dout) with a mean value of 73.57 nGyh−1, the indoor absorbed dose rate (Din) with a mean value of 131.84 nGyh−1, the annual effective dose rate (AEDR) with a mean value of 0.74, the radium equivalent (Raeq) with a mean value of 156.0, the internal hazard index (Hin) with a mean value of 0.51, the external hazard index (Hex) with a mean value of 0.42 and the excess lifetime cancer risk (ELCR) with a mean value of 2.57. Similarly, results obtained from estimated radiological parameters show that the station with the highest value for radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin), and annual effective dose rate (AEDR) is Station 9 at 237.91 Bq/Kg, 0.64, 0.72 and 1.13 mSvy−1 respectively while the station with the lowest value for radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin) and annual effective dose rate (AEDR) is Station 17 at 85.58 Bq/Kg, 0.23, 0.27 and 0.40 mSvy−1 respectively. This study will serve as a guide on assessing the road construction materials on radioactive contents before application to reduce the exposure risks to the populace along the busy roadsides.

EFFECTS OF WASTE CROSSED-LINKED POLYETHYLENE ELECTRICAL WASTE COATING ON THE PROPERTIES OF BITUMEN

The high cost of construction materials and increased axle loads has motivated researchers to seek alternative cost-effective materials for road construction. Studies on the use of waste thermoplastic polyethylene material to improve bitumen properties have been investigated. However, few studies on the use of thermoset polyethylene (cross-linked polyethylene) to modify bitumen have been carried out. This research investigated the use of waste cross-linked polyethylene (XLPE) cable coating on bitumen properties. An FTIR analysis carried out on waste XLPE cable coating revealed that it is predominantly composed of XLPE material. A comparative study carried out on the bitumen properties revealed that the modifier had a decreasing effect on its penetration and ductility but, had an increasing effect on softening point and specific gravity; Hence, a considerable improvement in the temperature susceptibility and stability of the bitumen. The short-term ageing analysis carried out revealed that the modified bitumen can withstand short-term ageing requirements at 2% and 4% by weight of pure bitumen. FTIR analysis carried out on the pure and modified bitumen revealed that changes observed in bitumen properties with increasing modifier content were a result of physical changes and not chemical changes. A one-way ANOVA carried out on the properties of various bitumen content revealed that the modifier had a significant effect on the properties of pure bitumen with increasing bitumen content. The regression models developed properly described the relationship between the modifier content and the bitumen properties as they expressed very good R2 values.

ОГЛЯД МЕТОДІВ ПІДБИРАННЯ СКЛАДУ АСФАЛЬТОБЕТОННИХ СУМІШЕЙ

Introduction. Asphalt mixtures are the most widely used road construction material for the arrangement of the top layers of road pavement. Asphalt mixtures are also used to arrange airfield runways, bridges deck surfacing, streets, pedestrian and cycle paths, etc. There is a large number of asphalt mixtures types that differ by grading, the largest nominal aggregate size, crushed stone content, crushed and uncrushed sand content, quality of components, and viscosity of the bitumen binder. Problem statement. The national method for asphalt mixture design is very similar to the Marshall method and the Superpave method in terms of determining the optimal bitumen binder content by the bulk properties of asphalt concrete. The only difference is that, according to the Marshall and Superpave methods, the optimal bitumen content is the one with an air pore content of 4.0 %. However, in accordance with the national method, the design air pore content varies depending on the type of asphalt mixture. A significant innovation of the Superpave method is the determination of asphalt performance indicators, such as rutting resistance, crack resistance, and resistance of the material to fatigue cracking. Apparently, these methods should also be implemented in Ukraine over time. Purpose. Analysis of the methods for asphalt mixtures design. Materials and methods. Analysis of literature sources on various methods of asphalt mixtures design. Results. The analysis of literary sources on different methods of asphalt mixtures design was carried out. Conclusions. The use of different methods of asphalt mixtures compaction can lead to the production of asphalt concrete with different volumetric properties, which will affect both the optimal bitumen content and the performance of asphalt concrete, thus further research should be aimed at defining the effect of the compaction method on the volumetric properties of asphalt concrete and their relationship with the production compaction of asphalt mixtures.

The Effectiveness of Residual Soil, Orashi River Sand, and Sombrero River Sand as Stabilizing Agents for Subgrade Soil of Highway Pavement

The study investigated the effect of different stabilization materials, including residual soil and river sands, on the properties of subgrade soil for road and pavement structures. The results showed that the chemical composition of the subgrade soil was dominated by calcium, aluminum, and silicon, indicating a mineral clay soil. The use of stabilization materials led to a decrease in fines content and an increase in maximum dry density. The behavior of optimum moisture content was non-linear, and the liquid limit of the stabilized subgrade soil decreased significantly for all three materials, indicating a decrease in soil swelling ability. The study also revealed that the use of composite materials of cement and residual soil or river sand can improve the properties of subgrade soil and lead to an increase in unconfined compressive strength. The findings of this study can aid in the selection of appropriate stabilization materials and methods, and in the optimization of the use of these materials in road construction for improved strength and durability. Further research is needed to fully understand the characteristics of subgrade soil and determine the most effective methods for its stabilization and management. This study investigates the effects of residual soil and river sands on the mechanical properties of subgrade soil, with a focus on liquid limit, plastic limit, plasticity index, and unconfined compressive strength. The results suggest that residual soil, Orashi River sand, and Sombrero River sand are effective stabilizing agents for subgrade soil, with an increase in strength observed with increasing percentages of stabilizing material. However, there is an optimum content of stabilization material required to achieve maximum strength values, beyond which the strength decreases. The study also highlights the importance of considering the effect of soaking on the strength of subgrade soil and demonstrates the effectiveness of using composite .........

Laboratory investigation on cement-treated recycled concrete aggregate bases for flexible pavements

India's economy is progressing fast, and many infrastructure development programs are going on. Especially the road network expansion is going on many folds. As a result, natural coarse aggregates are getting depleted, which has an impact on environmental sustainability. Utilizing the resources from the many aged and demolished structures will be cost-effective and solve the disposal problem of these wastes. India's government insists on using marginal material, demolished waste, or recycled aggregates as alternative materials for road construction. New codes developed by IRC and MoRTH recommend Cement Treated Bases (CTB) and Cement Treated Sub-Bases for pavement lower layers. In light of this, the present study attempts to utilize Recycled Concrete Aggregates (RCA) obtained from construction and demolition (C&D) waste in the CTB. The efficiency of RCA was checked at various replacement levels ranging from 0% to 100% with cement stabilization of 3%, 5%, and 7%. The strength properties like Unconfined Compressive Strength (UCS), Flexural Strength and durability were evaluated. The microstructural characteristics and elemental analysis of the cement treated recycled concrete aggregate mixtures were examined. The research yielded the highest potential RCA of up to 50% with a cement content of 5%, meeting the Indian Road Congress (IRC) criteria for CTB.

ĐÁNH GIÁ KHẢ NĂNG ỨNG DỤNG PHỤ GIA XANTHAN TRONG XÂY DỰNG THÔNG QUA KẾT QUẢ THÍ NGHIỆM ÉP KÉO VÀ THÍ NGHIỆM CƯỜNG ĐỘ

Xanthan is a natural polysaccharide in powder form, created through the fermentation of sugar by the bacteria Xanthomonas campestris. In construction, Xanthan has been researched and applied in road and bridge construction materials, viscosity adjusting additives in selfcompacting concrete... and in construction materials technology in general, Xanthan is used as a viscosity modifier, thickener... in concrete. In this study, the applicability of Xanthan in concrete was preliminarily evaluated. Through the results of squeeze - tack experiments to evaluate the rheological behavior of Xanthan pastes, the author conducted a compression test with concrete using Xanthan additive (2%), evaluating the change in strength of concrete when using Xanthan. The results show that Xanthan can be used in concrete to improve adhesion to the mold and increase the ability to easily peel off the mold. At the same time, using Xanthan in concrete with a content of 2% also contributes to increasing the compressive strength of concrete with an increase of 7%.

Red mud-slag blends as a sustainable road construction material

Red mud is a highly alkaline solid waste that contains significant amounts of heavy metal ions. This causes serious environmental issues if disposed of unscientifically. Thus, developing an economical and eco-friendly technique for utilization of red mud can solve the disposal problem efficiently. The present study deals with the evaluation of physical, mechanical and chemical properties of red mud treated with ground granulated blast furnace slag to assess its suitability as a construction material for highways. To accelerate the geopolymerization process, additional doses of alkali activator is used. Mineralogical and microstructural analyses have been made to identify the geopolymerization products. An optimization technique is adopted to find out the optimum slag and alkali dose to have the highest strength. The durability of stabilized red mud has been assessed under slaking fluid. Leachate analysis has been carried out on source materials and stabilized materials to examine the levels of major and trace elements. It is observed that the alkali present in red mud can initiate geopolymerization reaction upon the addition of slag. However, additional alkali is needed to accelerate the geopolymerization reaction. Stabilized red mud performed good strength and stability. The alkalinity is reduced after stabilization and the heavy metals are encapsulated by geopolymeric reaction products. Target strengths for different constructions can be achieved with appropriate combinations of slag and alkali.

Effects of Mellowing Practice on the Strength and Swelling Properties of Road Construction Materials: Case of Sulphate-Bearing Clay Soils Stabilised with Lime-Silica Fume Blended Binder

The main thrust of this research was to establish any benefits of mellowing, and the optimal moisture content (OMC) for compacting mellowed sulphate-bearing clay soil undergoing the stabilization process. Two three-day mellowing regimes were carried out, prior to final compaction, at different initial moisture contents of 30% or 40% OMC. The unmellowed specimens were compacted immediately after mixing with the blended stabilizers. A blend of quicklime (L) with a sustainable by-product, silica fume (SF), at a 1:1 ratio (2%L-2%SF) was used. Linear expansion and unconfined compressive strength (UCS) tests were carried out to evaluate the benefits of mellowing. The test results suggested that the mellowed test specimens achieved better UCS and swelling properties compared to the unmellowed specimens. Mellowing at 1.2 OMC produced better strength performance than at 1.4 OMC, whereas mellowed specimens at 1.4 OMC showed better resistance to linear expansion compared to 1.2 OMC. The research findings suggested that optimal performance was achieved by mellowing at the higher initial moisture condition of 40% OMC and compacting the materials at the lower moisture condition of 1.2 OMC.

Chemical fingerprinting of volatile organic compounds from asphalt binder for quantitative detection

Asphalt material is an irreplaceable material in road construction. However, it releases VOCs (Volatile Organic Compounds), which do cause pollution to the surrounding environment, during its full life cycle, especially in high-temperature paving stage and summer service time. Asphalt VOCs release mechanism and effective emission reduction technologies are therefore urgently needed. The chemical analysis of VOCs from asphalt binder always invariably excludes a vast number of compounds of unknown relevance, making the quantitative analysis lower data accuracy. In order to address this problem, fingerprint database was developed and introduced in this study, with the detected VOCs data from 104 kinds of asphalt binders. The analysis parameters, including fingerprint components and calibration curves were optimized through quantitative study. With the help of a self-developed fingerprint database, the calculation formulas of single VOC and total released VOCs were established for quantitative analysis of VOCs from asphalt binder. In addition, the influencing mechanism of heating temperature and asphalt types on VOCs volatilization characteristic were explored to achieve emission reduction in asphalt industry.

Performance assessment of full depth asphalt pavements manufactured with high recycled asphalt pavement content

Reclaimed asphalt pavement (RAP) is generated during road rehabilitation and resurfacing projects. This highly valuable recycled material should be used for manufacturing fresh hot mix asphalt (HMA) for new asphalt pavement layers to ensure the highest added value and minimise environmental impact. The use of RAP is already common practice worldwide; however, incorporating RAP into the manufacturing of HMA is still very minimal in Hungary. As part of a research work HMA containing 20-50% RAP was designed, manufactured and tested. This paper discusses the performance tests carried out on laboratory and plant mixed asphalt mixes; using this data the overall full depth asphalt (FDA) pavement performance was predicted through general mechanistic pavement design. The outcomes of this paper showed that high RAP content asphalt mixes can have superior performance; this disproves the common perception that high RAP mixes are substandard road construction materials. The analysis performed in this paper found that asphalt mixes with high RAP content present low risk for in-situ performance. However, in order to achieve this outcome, the application of correct mix design methodology, appropriate RAP management and suitable asphalt plant capability for mass production are paramount.

Analysis of obtaining an economical road construction material based on ash

Analysis of obtaining an economical road construction material based on ash

Comparison of the Number of Compactor Passes and the Constrained Modulus of a Compacted Volcanic Soil

Volcanic soil is often used as fill material in road embankment construction in Java island-Indonesia. An understanding of the engineering properties of compacted volcanic soils is needed, especially during the preliminary design phase and during the detailed design phase of the road embankment. Carrying out a field compaction trial test will significantly assist in the design of the compaction process of the road embankment construction. Selecting the correct number of passes from the compactor and the engineering properties of compacted volcanic soils can be obtained from field compaction trial tests. Constrained modulus is one of the engineering properties that can indicate the stiffness of the fill material used in a road embankment. This study aims to determine the constrained modulus of compacted volcanic soil and compare it to the number of passes of a compactor from the field compaction trial test. The volcanic soil used in this study is classified as pumiceous tuff, which is derived from older volcanic rocks. The highest value of the oedometer modulus of compacted volcanic soils is 10.38 MPa which comes from eight (8) times passes of smooth drum roller conducted on field compaction trial test.

EXPERIMENTAL RESEARCH DETAILED INDICATORS OF CEMENT-STABILIZED SOIL COMBINED EVOCRETE ST ADDITIVE

Statement of the problem. Under the conditions of intensive development of the world road transport infrastructure, there is currently a shortage of high-quality road construction materials. One of the key solutions to address this problem is to use stabilized soil with inorganic binder to make the pavement construction. Results. The paper presents an overview of the study results in evaluating the ability to use stabilized soil with inorganic binders, and other inorganic adhesives combinations for pavement construction. The study also shows the different levels of indicators of cement-stabilized soil combined Evocrete ST additive. Conclusions. It can be seen that the effectiveness of using Evocrete ST additive with a content of 3-5 % combining cement to stabilize the soil. The study proposes to use cement-stabilized soil combined Evocrete ST additive to make different type of pavement constructions.

THE EFFECT OF MINERAL ADDITIVES ON THE PHYSICAL AND MECHANICAL PROPERTIES OF REINFORCED ORGANIC MINERAL SOILS

Statement of the problem. The aim of the work is to study the effect of mineral additives on the physical and mechanical properties of Portland cement-reinforced soils with a high humus content, as well as to assess the possibility of using these soils in road construction. Results. In the course of the study, the values of the strength and the coefficient of frost resistance of organic and mineral soil compositions with the content of humus substances reinforced with a mineral binder with the addition of sand in different proportions were determined. To compare the effect of mineral binders (cement) and an additional (polymer additive) on the structure of the resulting material, cement was used both in pure form and cement in combination with a polymer additive. The use of sand as a structural aggregate makes it possible to apply a soil with a high content of humus substances, reinforced with binding materials, in the structures of road clothes. Conclusions. Various compositional compositions of soil strengthening with the use of Portland cement as binders, polymer additives, slaked lime using sand as a mineral filler are proposed. The reinforced soil, depending on the area of application, can be used as a base of a transitional type of pavement and an additional layer of a lightweight type of pavement base, which will reduce transport costs for the delivery and payment of road construction materials.

Mechanical properties and heavy metal leaching behaviors of municipal solid waste incineration bottom ash as road embankment fillings

With the development of economy and urbanization, the natural gravels and sands for new road construction materials encountered severe shortage issues in recent decades. In the meantime, the municipal Solid Waste Incineration bottom ash (MSWIBA) is regarded as a feasible alternative of mined nature aggregates due to its similar mineralogical, physical and chemical characteristics. However, the uncertainties of long-term service performance and potential environmental pollution risk of MSWIBA prevent its widespread applications in road constructions. For these reasons, this paper investigates the resilient modulus and permanent deformation properties by the repeated load triaxial test at different moisture contents, and examines the long-term environment influence using leaching tests on the samples after subjecting to 5 freeze-thaw cycles and samples after one year weathering. Besides, the existing resilient modulus and permanent deformation prediction models of unbounded granular materials are evaluated for their applicability on MSWIBA. The test results indicate that the MSWIBA shows obvious stress-dependence and moisture-dependence in resilient modulus and permanent deformation behaviors. Moreover, the existing resilient modulus and permanent deformation prediction models with stress and moisture dependence are feasible for MSWIBA as well. Additionally, heavy metal leaching concentrations obtained from column test can meet the standard of surface water quality class V in China. This work is expected to benefit the design work and provide the insight of performance of MSWIBA as road embankment material, and promote its further widespread application in road construction.

Overburden Recycling in Manufacture of Composite Materials for Road Construction at Mines

Overburden Recycling in Manufacture of Composite Materials for Road Construction at Mines