Road Structure Research Articles

The use of drainage geocomposites in cold regions

When designing road structures in cold climates, engineers must consider frost heave, a natural process that involves the cyclic freezing and thawing of water in soil or rock. The formation of ice lenses as water separates from the soil when the ground freezes is the primary cause of frost heave, and its effect on road structures depends largely on soil particle size. Frost heave damage is more noticeable in fine-textured soils that promote capillary uplift and is more destructive in the spring due to the influx of water from melting snow and ice. One possible solution to prevent road structure deformations caused by frost heave effects is the use of drainage geocomposites. Polymeric geocomposites have been widely studied and used worldwide in transportation infrastructure for drainage or as an anticapillarity layer. It is important to note that their performance is affected by temperature variations, and while many studies and regulations have focused on temperatures above 20°C, there is limited information available for cold climates.

Comparative analysis of the response of the road structure with full/partial interlayer connection to traffic action

This article investigates the response of the road pavement of a road sector analysed to the action of traffic that was determined numerically by using two dedicated software. In this respect, the Romanian program CALDEROM 2000 (PD 177, 2001), respectively the French program for calculating the road pavements ALIZÉ-LCPC were used. Both programs use the Burminster elastic model for the analytical evaluation of stress states and specific deformations in multilayer road pavements. However, unlike the CALDEROM 2000 program, the ALIZÉ-LCPC software allows the user to define the interfaces between layers and switch loads from single axle to multiple loads, being a rational method, based on the determination of the resilient stresses and deformations in road structures by using the classical linear elastic multilayer model. The aim of this study was to determine whether the road pavement with deficiencies of adhesion between layers is able to take over the calculated traffic considered in the project, possibly the proportion of calculation traffic that can be taken over, which would allow an assessment of the capable operation life of the road pavement and, implicitly, of the possibility of its yielding before the end of the perspective period considered.

Geosynthetic solutions for road stabilization and railway ballast optimization over frost susceptible and expansive clays: A case study of the Cargill Canola processing facility

The Cargill Canola processing facility, a $350 million project, began construction in July 2022 and is set to be operational in 2025. The site's geology primarily consists of fine-grained glaciolacustrine sediments, mainly silts and clays. A significant geotechnical challenge was the presence of a weak upper silty clay soil layer, approximately 10 metres thick, which was susceptible to frost heave during freezing temperatures and volumetric changes due to water exposure. Spring melt also raised concerns about excess water accumulation weakening the subgrade, leading to structural damage. The high plasticity index of the subgrade increased the potential for swelling in warmer conditions, complicating the design challenges during seasonal transitions. To address these issues, geosynthetics were employed. Three types were used: a moisture management woven geotextile to provide hydraulic and mechanical stabilization in the rail and road structures, an integrated high-modulus woven geotextile to provide ballast reinforcement, and a biaxial geogrid for base reinforcement in the access roads. The integrated high-modulus woven geotextile was also used in staging areas and gravel pavements to reduce the amount of granular base material required. This case study offers valuable insights for geosynthetic solutions in stabilizing roads and optimizing railway ballast over frost-susceptible and expansive clays. It demonstrates the effectiveness of geosynthetics in mitigating challenges posed by weak soils, frost susceptibility, and expansive clays, contributing to more resilient infrastructure designs.

Evaluation of Parameters Service Standard Minimum (SPM) Based on Perceptions of Road Users National Segment Kayee Lon - Meulaboh

In an effort to address community needs and assist the acceleration of regional economic development, road construction has become a government priority. The problem in road services is that the Minimum Service Standards (SPM) have not been met based on the functional indicators of road sections, road structure and road safety. Road SPM refers to the provision of roads to meet the needs of the community in terms of the physical size of the road in accordance with certain technical criteria. The government, as the operator of the road, is required to carry out the legal mandate as a form of service to the community using the road. The purpose of this study was to determine the service quality of the Kayee Lon - Meulaboh National Road Segment based on the level of importance and performance and to find out which variables are the top priority for improving performance. To perform this study, 135 randomly chosen respondents were given questionnaires on a Likert scale, and the data was processed using the IPA (Importance Performance Analysis) method. The service quality of the Kayee Lon–Meulaboh National Road Segment with Functional Indicators of Road Sections is at the “Important” level with a mean of 3.924 and at the “Moderate” level with a mean of 3.400 based on performance level. Structural indicators of road sections are at the “Important” level in terms of importance, with a mean of 4.189, and at the “Moderate” level in terms of performance, with a mean of 2.995. The Road Safety Indicator is at the “Important” level based on importance, with a mean of 3.924, and at the “Not Good” level based on performance, with a mean of 2.171. Lane width is the factor whose performance has to be enhanced as a top priority for Road Section Functional Indicators. Pavement surface drainage and crack width are two variables that need to perform better in relation to the Road Section Structural Indicators’ top priority. Variables that need to be improved in terms of performance as a top priority for Road Safety Indicators are street lighting, zebra crossing and crossing facilities.

Large scale trial evaluation of granular layers reinforced with geocells

Geocells are three-dimensional geosynthetics made up of interconnected cells that confine the granular materials embedded in them. This confinement generates an increase in the rigidity and a decrease in the deformability of the reinforced layer, allowing for better performance of the pavement and optimization of non-renewable stone materials in transport infrastructure reinforcement applications. This study presents a full-scale test that consisted in the construction of a full-scale field with the aim of evaluating the behavior of granular materials with and without geocell reinforcement in transportation infrastructure. The experimental full-scale field is made up of five sections, the structure of this unpaved road consists of two layers of granular subbase material reinforced with two different geocells located at different depths, these layers are built on a clayey subgrade of low capacity. Material characterization tests were carried out and the subgrade and granular layers were subjected to measurements with the Benkelman Beam. Results from field measurements indicate that geocell reinforcement can reduce deflections at the top of granular layers and the MIF (Modulus Improvement Factor) can be calculated for the different geocells. The test results indicate that inclusion of geocell reinforcement significantly improves the rutting resistance and stability of reinforced test sections compared to the unreinforced test section.

Performance of asphaltic concreate binder course (AC-BC) using gilsonite modified asphalt

The road pavement structure is the most important part of the design and manufacture of highways, so there is a need for innovation in designing pavement to get a type of pavement that has good quality and is efficient in its design. At this time, many road pavements have suffered damage caused by poor quality. Gilsonite is a natural asphalt that has a relatively high asphalt content compared to other additives, which is 70.9%. In addition, Gilsonite has a maltene content of 27% and 2% oil, then has a nitrogen content of 3.2%. After that, to carry out this test, a test object was made with the addition of Gilsonite Resin using 3 variations of the addition, namely 6%, 7%, and 8%, and compared to the mixture without Gilsonite. The mixture using the addition of Gilsonite (6%, 7%, 8%) an increase in the stability value of the mixture using the addition of Gilsonite, but the flow becomes increased so the properties of the mixture have large deformations. From all the tests that have been carried out, the optimum Gilsonite content is 8%

МЕТОДИЧНІ ПІДХОДИ ДО ОЦІНКИ ТЕХНІЧНОГО ЗАБЕЗПЕЧЕННЯ АГРОБІЗНЕСУ

The technical base is the material basis for the production capabilities of farms. The availability of machinery and the efficiency of its use are determined by the strategic development of enterprises. The issues of formation and efficient use of the resource potential of enterprises in order to increase the competitiveness of agriculture and the national economy as a whole are becoming increasingly important. To date, agroeconomic science has formed the main methodological directions for assessing technical support: the first involves determining its absolute value, and the second - the normative value based on available technical resources. Quantitative assessment of the production potential is established by determining the total value of technical resources at the disposal of agricultural enterprises. This involves comparing heterogeneous production resources (monetary valuation of all components of the resource potential, valuation of technical resources in natural units, determination of their quantity and value per area of agricultural land, etc. The normative value of fixed production assets is calculated in accordance with the performance indicator (the amount of a certain type of product produced, yield, average milk yield, etc.). The analysis of the provision of agricultural enterprises with technical means can be carried out according to the following scheme: assessment of the provision of technical means and efficiency of enterprises; financial analysis of enterprises' activities, comparative analysis; organization of the procedure for assessing the technical resources of enterprises. Three methodological approaches are used for generalized assessment of technical support in agriculture. They are based on various statistical models (deterministic and stochastic) that substantiate the link between the availability of technical resources and production outcomes; normative (standardized) values of the availability of certain types of technical resources, the total availability of which is correlated with the average or base value; and monetary assessment of the components of the technical and technological base of agriculture. The specified indicators make it possible to analyze more deeply changes in the absolute and specific sizes of the main means of production for various production purposes, including technical resources, their species composition and structure over a number of years, average annual growth rates and growth, which makes it possible to establish trends in the dynamics and their movement, apply their rational road structure and dimensions, which ensures the growth of indicators of economic activity, outline and develop recommendations for improving the structure of the material and technical base, its effective use.

2T3C apparatus and DIC technology to investigate the thermomechanical behaviour of the interface between bituminous layers

The bonding at the interface is seen in most road structure design methods as perfectly bonded and this ideal condition is supposed to last during the whole service life. However, the real working capacity at the interface is complex and gradually degrades because of repeated traffic load and weather conditions. A new apparatus called 2T3C (“Torsion, Traction, Compression sur Cylindre Creux” in French, or “Torsion, Tension, Compression on Hollow Cylinder” in English) was developed at the ENTPE/University of Lyon to investigate the thermomechanical behaviour of the interface between bituminous layers. The sample has two layers of similar or different materials. It has a total height of 125 mm and a wall thickness of the 25mm. The thickness was chosen small enough in order to validate the assumption of quasihomogenous stress and strain fields between inner and outer surface. The DIC technology is performed considering the three listed elements: (1) two couple of cameras are situated on two opposite sides of the sample (4 cameras in total) to take 3D images; (2) a software is employed to calculate the displacements in 3 dimensions of all points in the area of interest; and (3) the strain fields in the 2 layers and the displacement gap at the interface are computed using a method developed at the University of Lyon/ENTPE. In this paper, a focus is proposed on the viscoelastic and fatigue behaviours of the two bituminous layers and of the interface. Small and large numbers of loading cycles are successively considered in the small strain domain.

Mechanical properties of reinforced loess soils in road pavements

The modern development of road construction promotes the tasks of not only increasing the strength of road structures, but also the need to effectively use local materials and soils in road construction. During the design and construction of highways, many road scientists of the world have carried out their scientific and research work on soil strengthening based on the road bed. Several methods and techniques have been developed for this. Also, developed countries are producing a lot of surfactants, modifiers and additives for soil strengthening. In this article, research work was carried out in laboratory conditions to study the mechanical properties of soil strengthened with the help of a modifier. Measurement, comparison, experimental laboratory, mathematical statistical analysis in the processing of test results, analytical methods specified in regulatory documents were used in the performance of research work. The results of the conducted laboratory research are specific to loess soils found in the conditions of Uzbekistan. The use of construction work on the foundation of the road bed from reinforced soil allows to reduce the volume of construction work, reduces the consumption of transported sand and gravel materials, and increases the service life of the road.

Lab-scale environmental impact measurement of polymer-modified asphalt concrete mixtures production

This study aims to evaluate and compare the environmental impact of producing numerous polymer-modified asphalt concrete mixture types for road structures at the laboratory scale measured by air quality monitoring devices in a designed isolated area. Several mixture combinations were examined in this study, namely between the production of the standard hot mix at 160oC (case 1) and polymer-modified warm mix asphalt with 5% and 6% polymer dosages at 130oC (case 2 and case 3), as well as the production of hot mix asphalt using polymer modification by wet mix - known as polymer modified binder/PMB at 180oC (case 4) and dry mix methods using 5% and 6% polymer dosages at 160oC (case 5 and case 6), with each case represented by five samples fabrication. Case 4 yields the highest carbon dioxide, the volatile organic compound (VOC), formaldehyde (HCHO), and particulate matter (PM10 and PM1) by a total of 8195ppm, 10.12ppm, 6.5ppm, 1643 µg/m3, and 838 µg/m3, respectively, except PM2.5, where the outcome of case 3 is 1.2% higher than case 4. Meanwhile, the lowest emissions are recorded for case 2 and case 5, with the ratio to case 4 ranging from 43.5% to 96.5%. The heating phase generally gives the highest contribution to the total result, with the proportion ranging from 43.5% for carbon dioxide to above 90% for particulate matter. To sum up, producing hot mix asphalt with PMB and the mixer blending stage generates the highest emission.

Analysis of the cold recycling asphalt pavements method from Romania

The present paper presents a documentation on the realization of the dosages from recycled mixtures, highlighting the change in the test methods regarding the composition and the determination of the physical-mechanical characteristics according to the latest technical regulations. Practically, the structure of the new norm for cold recycled road materials aligns with the new European requirements in accordance with the provisions that the mixtures must meet, but still the problem remains on how to prepare the samples in the laboratory and determine the value of the stiffness modulus of the considered mixture, value which practically in the norm is considered based on good practice. Determining the real value of the stiffness modulus is a decisive factor in the dimensioning of the road structure reinforcement because it can considerably influence the thickness of the layers that make up the resistance structure. Therefore, the paper presents a study on the new methods of making samples in the laboratory and values of the stiffness modulus taken into account when dimensioning the reinforcement of road structures according to the composition of the considered materials.

Risk assessment of ANAS tunnel stock in the north-east of Italy and the case study of the SHM of Comelico tunnel

The management of tunnel safety is a crucial element for the protection of road infrastructure, user safety, and the preservation of structural durability. In this context, the framework agreement between the National Autonomous Roads Corporation (ANAS) and BOLINA Engineering plays a significant role, focusing efforts on the road network in Northeast Italy and adopting advanced practices in compliance with current regulations to ensure the safety of numerous tunnels within the ANAS network. The recent Guidelines for Tunnels (Ministerial Decree number 247 of August 1, 2022: Approval of Guidelines for classification and risk management, safety assessment, and monitoring of existing tunnels along state roads or highways managed by Anas S.p.A. or highway concessionaires) constitute a robust regulatory framework for tunnel safety management, proposing a tailored, layered approach based on the criticality of individual structures. In this context, BOLINA Engineering, as a strategic partner of ANAS, actively engages in engineering activities aimed at assessing tunnel safety.Within the scope of the received mandate, BOLINA operates by focusing on the determination of the Attention Class, a crucial phase for tunnel safety management. This process involves various stages:Information Collection: Involves acquiring all design data and documenting structural characteristics through the completion of an identification form for each tunnel.Direct Visual Inspections and Surveys: Include direct visual investigations and rapid surveys of the structure, along with the analysis of geomorphological and hydraulic features. This phase aims to identify existing degradation, geometric and structural properties, and potential associated risks.Risk Parameter Assessment: Based on the assessment of hazard, exposure, and vulnerability parameters derived from previous investigations. This phase assigns an Attention Class to each tunnel (High, Medium-High, Medium-Low, Low), determining subsequent actions needed to ensure structural safety.The goal of this synergy between ANAS and BOLINA is to ensure the safety and durability of structures, with particular attention to the needs of the road network in Northeast Italy. The aim is to achieve an exemplary infrastructure management model by integrating the best engineering practices with regulatory provisions, ensuring user safety and the long-term preservation of road structure integrity. Subsequently, an overview of ongoing activities will be presented, followed by the presentation of a specific case representing the work conducted on each tunnel within the examined asset.

2D temperature field analysis of asphalt pavements with three different types of subgrade structures

To explore the temperature distribution in width and depth of asphalt pavements with three different subgrade types, a numerical model is established. Based on actual meteorological data, the lateral temperature differences (LTDs) along the depth direction of pavement layers were analyzed under diurnal periodic thermal boundary conditions. Results reveal that the maximum LTD on the surface of a part-cut part-fill subgrade roadbed structure, as represented by a mountainous road, can reach 6.3 °C and 10.8 °C during winter and summer, respectively. The LTDs vary periodically with the boundary conditions. The LTDs on the road surface with high solar radiation in summer are 2.6–7.6 °C higher than those in winter. The influence ranges of the LTDs along the width direction of the road in winter and summer are 0–300 mm and 0–350 mm, respectively. This study provides a more precise method for studying the temperature field of road structures, which is helpful in analysing the pavement damage caused by thermal stress, etc. It also provides the necessary reference for the practical implementation of new technologies in the fields of asphalt pavement thermal energy storage systems and asphalt pavement temperature difference power generation.

3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles

3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles

RCYOLO: An Efficient Small Target Detector for Crack Detection in Tubular Topological Road Structures Based on Unmanned Aerial Vehicles

RCYOLO: An Efficient Small Target Detector for Crack Detection in Tubular Topological Road Structures Based on Unmanned Aerial Vehicles

Review of Subgrade Soil Stabilised with Natural and Synthetic Fibres

Subgrade soil is an essential component in the design of road structures as it provides lateral support to the roadway. One of the main reasons for pavement failure is subgrade settlement, which leads to a loss of subgrade strength. If the mechanical properties of subsoils are lower than required, a soil stabilisation method may be an option to improve the soil properties of the weak subsoil. Soil stabilisation is one of the techniques for improving poor subsoil, which results in significant improvement in tensile strength, shear strength and bearing capacity of subsoil. Soil stabilisation can be broadly divided into four types: thermal, electrical, mechanical, and chemical. The most common method of improving the physical and mechanical properties of soils is stabilisation with binders such as cement and lime. However, soil stabilisation with conventional methods using cement and lime has become uneconomical in recent years, so an alternative such as fibres may be sought. This review provides a comprehensive comparison of the effectiveness of natural fibres and synthetic fibres in stabilising subgrade soils.

Application of dynamic complex stiffness modulus master curves of HMA with recycled materials in the mechanistic-empirical design of road pavement structures

The main objective of the paper is to present the possibilities and advantages of advanced methods for determining the viscoelastic properties of asphalt mixtures produced using recycled materials in individual mechanistic-empirical pavement design. The use of various types of materials in asphalt mixture production can significantly alter their functional parameters, such as the dynamic stiffness modulus. In addition, this parameter changes with the change in the temperature of the road pavement and the speed of vehicles. In order to determine the durability of the pavement structure in an informed manner and minimize the risk of error, it is necessary to investigate and describe as precisely as possible this variability in the behavior of asphalt layers as a result of changes in the properties of input materials, e.g. by the addition of recycled materials and under the influence of changes in temperature and load velocity of the pavement. The most effective approach involves the application of master curves of the dynamic complex stiffness modulus of asphalt mixture, constructed based on research results conducted at different temperatures and loading frequencies. This allows for the determination of stress and deformation states of the pavement construction under various climatic conditions, utilizing seasonal or average monthly temperatures and considering the specific characteristics of pavement operation, such as different vehicle speeds for main routes, connectors, or street intersections. The paper compares the changes in dynamic modulus master curves for different types of asphalt mixtures with and without the addition of waste or recycled materials such as reclaimed asphalt pavement (RAP), rubber from used tires, or synthetic fibres and changes impact on the estimated durability of the pavement structure due to different approaches to determining climatic conditions and movement speed.

DETERMINATION OF THE COMPRESSION MODULUS WITH A DYNAMIC CIRCULAR PLATE

<p><span class="fontstyle0">Geotechnical soil tests in order to achieve the best possible performance of new buildings or rehabilitation of existing buildings occupy one of the leading places in construction. Due to the lack of investigative work, a large number of buildings are exposed to danger. In order not to have bad effects on buildings in the future, it is necessary to minimize ground subsidence. Testing of the compressibility modulus / determination of the compressibility modulus is performed during the construction of roads, railways, buildings, parking lots and embankments, on the foundation soil, replacement layers, bedding and embankment layers and buffer. The purpose of the test is to ensure that, due to insufficiently compacted layers during installation, they do not settle after some time, as well as cracking of the floor in the building, deterioration of part of the building, deterioration of the pavement structure of roads and parking lots (potholes), etc. A circular plate is the name for an instrument used to test the compressibility module of a building's foundation. A dynamic test with a falling weight plate enables simpler and faster testing and immediate results.</span></p>

DETERMINATION OF THE COMPRESSION MODULUS WITH A DYNAMIC CIRCULAR PLATE

<p><span class="fontstyle0">Geotechnical soil tests in order to achieve the best possible performance of new buildings or rehabilitation of existing buildings occupy one of the leading places in construction. Due to the lack of investigative work, a large number of buildings are exposed to danger. In order not to have bad effects on buildings in the future, it is necessary to minimize ground subsidence. Testing of the compressibility modulus / determination of the compressibility modulus is performed during the construction of roads, railways, buildings, parking lots and embankments, on the foundation soil, replacement layers, bedding and embankment layers and buffer. The purpose of the test is to ensure that, due to insufficiently compacted layers during installation, they do not settle after some time, as well as cracking of the floor in the building, deterioration of part of the building, deterioration of the pavement structure of roads and parking lots (potholes), etc. A circular plate is the name for an instrument used to test the compressibility module of a building's foundation. A dynamic test with a falling weight plate enables simpler and faster testing and immediate results.</span></p>

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.