Causes Of Pavement Failure Research Articles

INVESTIGATING CAUSES OF FLEXIBLE PAVEMENT FAILURE: A CASE STUDY OF THE BAKO TO NEKEMTE ROAD, OROMIA, ETHIOPIA

Most of the roads constructed in Ethiopia fail prematurely before serving the design life due to various causes arising from many factors. One of the roads that failed before reaching its design lifetime is the Bako to Nekemte Trunk Road. This road was constructed and opened to traffic in 2013. The design pavement life was estimated at 20 years. However; pavement failures have manifested since 2014 after it was opened for traffic. The main objective of this research was to investigate the cause for the failure of flexible pavement on the Bako to Nekemte road segment. To achieve this objective, the study was followed by the experimental research type and purposive sampling method. Also, field observation and pavement condition survey methods for data collection were used. The asphalt, base course, subgrade, and sub-base layer material sampled from the road segment are the material used for this study. Different pavement failures such as rutting, pothole, alligator cracking, raveling, edge cracking, depression, and corrugation were observed along the road section. For estimations of pavement condition index, the road was divided into five different sections based on distress densities, which were measured during the pavement condition survey. From those five sections, four sections were selected for the determination of the Pavement Condition Index (PCI). Using systematic random sampling 159 sample units were evaluated for Pavement Condition Rating (PCR) and the result shows 1.89% excellent, 8.18% very good, 20.13% good, 31.45% fair, 18.87 % poor, 18.24% very poor, and 1.26% failed. Based on PCI value, samples of pavement layer were taken from failed surface condition (1), poor surface condition (2), and none distressed area (1) for comparison purposes. Different quality tests like Atterberg limit, wash gradation, soil classification, compaction test, California Bearing Ratio (CBR), Los Angeles Abrasion (LAA), Flakiness Index ( FI), Aggregate Crushing Value (ACV), Ten percent fines value (TFV), bitumen content, and gradation of asphalt were carried out. The results of these tests were compared with ERA specifications to identify the probable cause of pavement failure. The study found that the cause for failure of flexible pavement in the case of Bako to Nekemte was: insufficient and absence of side drainage structure, traffic loading, poor gradation of base course and sub-base material, and poor quality of subgrade soil. The study also recommended that the road urgently needed routine maintenance as a treatment option to reduce further deterioration and extend its service time.

Subsurface Investigation for Road Construction Using Electrical Resistivity Method along Oloko road, Apatapiti, Akure, Ondo State, Nigeria

Abstract Evaluation of the shallow geologic materials in terms of types, nature, and bedrock structure as possible causes of pavement failure was carried out along Oloko road Apatatpiti, Akure, Nigeria, using Schlumberger vertical electrical sounding and 2-D imaging dipole-dipole techniques. Three lithological layers, namely thin top soil, weathered layer and weathered basement, were revealed by the 2-D resistivity structure. Vertical electrical soundings were made at locations with a very low resistive medium typical of linear features such as fractures/faults at some distances on the 2-D resistivity structure. Four geologic layers, namely the top soil, clay/sandy clay, fractured basement, weathered/fresh basement, were identified by the geoelectric section. The geoelectric section and the 2-D resistivity structure revealed that the upper 0-6m, which constitutes the subgrade, has a low resistivity (36 Ωm to 108 Ωm) characterised to be clayey materials and suggestive of weak zones that might impair the stability of the road. A relatively shallow depth, ranging from 3.7 m to 4.29 m, was the depth to the water table of the four wells close to the road. Therefore, the possible causes of pavement failure are the thick and low resistive layer, the near-surface linear features suspected to be fractures/faults, and the water table’s shallow depth.

Forensic Study on Federal Road Pavement Failures at Rengit and Semerah, Batu Pahat

Forensic investigations in engineering term may be conducted to identify the causes of failure to facilitate the design of proper repairs, or to improve the performance or lifespan of a component, assembly, or structure. This paper presents the combination of geotechnical investigation and geophysical survey method as a forensic tool to predict the causes of pavement failure occurred along the coastal area of federal road FT005. The number and type of field testing are varying on each selected study area at Rengit and Semerah, Batu Pahat as this location constructed on soft soil area. Non-destructive testing (NDT) method using electrical resistivity tomography (ERT) were chosen to be applied at the worst severity of the road failure. Three number of resistivity lines of 100m and 200m were laid out using ABEM Terrameter LS2 with gradient method of electrode arrays covering up to 40-meters depth. Then, further testing of destructive testing (DT) method using borehole drilling conducted near the ERT lines to obtain soil profile with SPT N-value measurement. The disturbed and undisturbed samples were obtained to carried out laboratory test for soil classification. After that, inspection of road pavement layers were implemented at five number of trial pit tests which excavated up to subgrade layer to determine the thickness of the materials used in road construction. Three number of mackintosh probe test were also conducted on top of the subgrade layer after the trenching to obtain the strength of the subgrade layer. The results presented showed that severe longitudinal cracking were the predominant premature failures on the roads studied due to settlement effect of soft soil. The analysis obtained from RES2DINV program stated that the subsurface profiling was dominantly in saturated condition which the resistivity value was less than 100 ohm.m. From the SPT N-value it is observed that, the very soft soil layer is up to 8 m followed by the soft to stiff clays soil. Another cause of failure was resulted from the differential settlement due to the effect of different design of road construction with varies material used. The reliability and efficiency of the instruments used were also discussed in this study.

Assessing the Extent of Pavement Deterioration Caused by Subgrade Volumetric Movement Through Moisture Infiltration

Pavements across Free State in South Africa often experience seasonal moisture variations that trigger, volumetric movement of the subgrade soil. The interaction of moisture-suction relationship and associated cyclic loads also contribute to pavement failure across this region. The current study investigated the failure cause of existing pavement structures constructed on expansive subgrades in the Free State province of South Africa. Material samples were collected from three representative sites by core drilling. Series of consolidated undrained triaxial tests (CU), free swell index (FSI) tests, zero swelling tests (ZST), filter paper tests, and unsaturated California bearing ratio ( $${\mathrm{CBR}}_{\mathrm{u}}$$ ) tests were performed to investigate causes of pavement failure through the principles of unsaturated soil mechanics. The results revealed that the investigated pavements deteriorate by swelling of the subgrades. The findings also evaluated that traffic loads significantly affected pavement structure as resistance failure to moisture were triggered from the asphalt layer. The asphalt thickness layer failed to provide sufficient surcharge pressure to confine swelling stress from the subgrades. The result further revealed that the $${\mathrm{CBR}}_{\mathrm{u}}$$ and matric suction decreased by 52.33% on average, with an increase in swelling stress as moisture content increases. The study suggested that seasonal moisture variations associated with excessive traffic load could be the main cause of pavement failure, as its pavement was designed for low to medium volume road users. In comparison, swelling stress values from the dry side were 8.63% higher than that of the swelling stress values obtained from the wet-side. The result further revealed that swelling stress was the major cause of the pavements' failure. Thus, as swelling stress increased with an increase in moisture; this consequently led to a considerable decrease in shear resistance and bearing strength capacity of the subgrades.

Various Types of Road Defects in Flexible Pavement and Maintenance

Various defects in versatile pavements are proverbial since the existence of versatile pavement. Pavement structure is additionally destroyed in an exceedingly terribly single season with water penetration .Defects in versatile pavements may well be a cringe of multiple dimensions, fantastic growth of machine traffic (in terms of no. of shaft loading of economic vehicles), the fast enlargement within the road network, non-availability of acceptable technology, material, equipment, labor and poor funds allocation have all else complexities to the matter versatile pavements. Maintenance is ready of activities directed towards keeping a structure in an exceedingly terribly serviceable state throughout its vogue life, Maintenance of a road network involves a spread of operations, i.e., identification of deficiencies and developing with, programming and programming for actual implementation within the sphere and looking out . The essential objective need to be to stay the amount and appurtenances in condition and to increase the lifetime of the road assets to its vogue life. Broadly, the activities embody identification of defects and to boot the potential cause there off, determination of acceptable remedial measures; implement these within the sphere and looking out at of the results. Pavement failure is written in terms of decreasing utility caused by the event of cracks and ruts. Before going into the upkeep ways in which, we tend to have to be compelled to check abreast of the causes of failure of pavements. Failures of pavements are caused to several reasons or combination of reasons. This paper summarizes the continued researches concerning the defects in versatile pavement and to boot the maintenance in versatile pavements. A well-developed transportation infrastructure is crucial for economic, industrial, social and cultural development of a rustic. Maintenance is ready of activities directed towards keeping a structure in an exceedingly terribly serviceable state throughout its vogue life, Maintenance of a road network involves a spread of operations, i.e., identification of deficiencies and developing with, programming and programming for actual implementation within the sphere and looking out . The essential objective need to be to stay the amount and appurtenances in condition and to increase the lifetime of the road assets to its vogue life. This paper discusses the potential causes of pavement failures, and recommend better ways in which throughout to attenuate and hopefully eliminate the causes of failures in pavements.

Development of Performance Grading Map of Nepal Based on Superpave System

The Performance of the bituminous binder plays important role in the overall performance of the pavement system. One of the major cause of pavement failure is the bitumen grade, i.e selection of suitable grade of bitumen. Therefore, performance grading of bituminous binder is inevitable for the specific temperature and climatic zones. This study is focused on the determination of performance grading of bituminous binder for various temperature zones in Nepal. In this study, twenty one years’ daily maximum and minimum secondary temperature data of 70 meteorological stations were collected and were analyzed for temperature zoning. Performance grading of bituminous binder was conducted with the help of Strategic Highway Research Program (SHRP) and Long-Term Pavement Performance Program (LTPP) prediction models. The concept of Superpave has been adopted for the analysis, which stands for superior performing asphalt pavement. The Superpave mix design includes a new analysis system based on performance characteristics of the pavement layer. The bituminous binder grades for Nepal have been determined on the basis of air temperature thereafter predicting the pavement temperatures. The study has determined seven different performance grade zones based on SHRP and four different performance grade zones based on LTPP model. The study synthesized the Performance Grade (PG) map of the country.

Characterization of asphalt binders blended with nanomaterial and polymer

Modification of bitumen binders with polymers and nanomaterials has successes in mitigating various major causes of pavement failures. The aluminum oxide nanoparticles (AI2O3) and Acrylate-Styrene-Acrylonhrtilrei polymer (ASA) were poured on the base bitumen binder 60/70 penetration grade with percentages of 3, 5 and 7% by the weight of bitumen binder. The outcome shows that the inclusion of polymer modified binders (ASMBs) and nanoparticles modified binders (ALMBs) matter has a great deal of impact on the rheological behavior of the bitumen binder at intense temperatures. However, the complex shear modulus (G*) improves the mix of the two modifiers. The increment at 75 °C was 63.70% for five percent ASBMs polymer, while for ALMBs, 71.12% for five percent. Although, the modified bitumen binders show high resistivity to rutting in intense temperatures, upon increment to 80% and 59% for five percent concentration of ASMBs as well as ALMBs chronologically. The refinement of bitumen binders gives an increase in the property of the binder which is the creep recovery for approximately about 69.23% and 62.53%. The use of ASMBs and ALMBs as discovered in this study shows that both modifiers above can mitigate the issues of the bitumen binder at intense temperatures, and five percent is regarded as the maximum constituent of the two modifiers.

A Multi-Dimensional Approach to Revealing Causes of Pavement Failures: Case Study of Minna – Suleja Highway, North-Central Nigeria

Remote sensing, geotechnical studies and geophysical data have been applied to determine the causes of the continuous pavement failure of the Minna – Suleja highway in a part of North-Central Nigeria. In this study, remotely sensed data in the form of Landsat 8 OLI and SRTM DEM were processed to extract structural lineaments and drainage pattern of the area. Geotechnical evaluation of soil samples such as grain size analyses, Compaction Test, Atterberg Limits and California Bearing Ratio (CBR) determination were also conducted. Geophysical data acquired were in the form of lateral resistivity profiling data at 500 m intervals and twenty-one Vertical Electrical Sounding (VES) spread across the selected sections of the road. Lineament analysis revealed predominant NNE-SSW trending structures. A notable percentage of the Lineaments trend NW- SE. Both sets of lineaments constitute a conjugate fracture system. CBR values in both portions range from 5 – 15% in soaked condition and unsoaked condition at OMC. Plasticity index range from 14 – 30 and 19 – 45 in both portions. Quantitative interpretation of the VES results established the presence of mostly three geologic layers which are: Clayey top soil, sand/lateritic sand and weathered basement. Resistivity values range from 20 Ωm to 300 Ωm for the top soil layer. The depths of this layer were generally less than 3 m. Preponderance of intersections of lineaments along failed portions account for near surface fractures, making these zones weak. This can be linked to low resistivity of the near surface materials and shallowness of the water bearing zones especially on the failed portions on which the road pavement foundation was laid. A distinction could not be made on the results of the geotechnical properties in both the failed and stable portions of the road. Hence, failure factors are not linked to the geotechnical properties of the soils.

Comparative Performance Evaluation of Effects of Modifier in Asphaltic Concrete Mix

This article describes how the gradual increase in traffic volume, poor design and construction practices and lack of attention to maintenance during the last few decades has caused an accelerated and continuous deterioration of the road network in Pakistan. The above factors are among the main causes of pavement failures, especially rutting. Rutting failure occurs when the pavement surface exhibits wheel path depressions caused due to softening of asphalt. In this article, different modifications were used in bitumen to reduce rutting, and compared it with unmodified bitumen. Low Density Polyethylene (LDPE) and crumbed rubber were used as modifiers. The compacted asphalt mixes were tested for resistance to rutting using wheel tracking machine at 25°C and 55°C temperatures. From this research, it is concluded that the crumbed rubber modified bitumen is a better option than LDPE, especially at high temperatures. However, conventional (unmodified) bitumen gives satisfactory performance at low temperatures.

The identification and treatment of poor durability Karoo dolerite base course aggregate - evidence from case studies

The Karoo Supergroup covers approximately 57% of South Africa's surface area and the sedimentary rocks therein generally do not yield acceptable pavement aggregates. The Karoo Dolerite Suite (intrusions) present in these sedimentary units have successfully been used as pavement aggregate sources, but numerous cases of premature pavement failure due to alleged rapid degradation of the dolerite have been reported. Durability tests are included in basic or mafic igneous rock aggregate specifications, but rapid pavement failures continue to occur. A study was recently undertaken to identify cases where degradation of Karoo dolerite was the cause of pavement failure. A secondary objective of the study was to determine if any observed degradation could have been identified using currently specified or alternative testing methods. Three such case study sites are presented in this article and the properties of their materials compared to those from five non-problematic dolerite materials. It is shown that the poor performance of the case study materials was likely due to the poor durability of the materials, manifesting as a reduction in resistance to abrasion and attrition. The identification of the observed poor durability could not have been performed accurately using only the currently specified test specifications. Alternative tests that allow an accurate differentiation to be made were, however, identified and, based on the results, tentative limits set. Additionally it was shown that modification of problematic Karoo dolerite base course materials, by applying lime at a rate less than the initial consumption of lime, can be successful in preventing further rapid pavement failures.

Study on Flexible Pavement Failures in Soft Soil Tropical Regions

Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

FDTD Simulation of the GPR Signal for Preventing the Risk of Accidents due to Pavement Damages

It is well known that road safety issues are closely dependent on both pavement structural damages and surface unevenness, whose occurrence is often related to ineffective pavement asset management. The evaluation of road pavement operability is traditionally carried out through distress identification manuals on the basis of standardized comprehensive indexes, as a result of visual inspections or measurements, wherein the failure causes can be partially detected. In this regard, ground-penetrating radar (GPR) has proven to be over the past decades an effective and efficient technique to enable better management of pavement assets and better diagnosis of the causes of pavement failures. In this study, one of the main causes (i.e. subgrade failures) of surface damage is analyzed through finite-difference time-domain (FDTD) simulation of the GPR signal. The GprMax 2D numerical simulator for GPR is used on three different types of flexible pavement to retrieve the numerical solution of Maxwell's equations in the time domain. Results show the high potential of GPR in detecting the causes of such damage.

Forensic Evaluation of the LTPP Specific Pavement Study Projects in Arizona

This paper presents a forensic investigation of selected Arizona specific pavement study (SPS) SPS-5 test sections. The investigation focused on identifying the causes of pavement failures, examining the pavement structural and functional performances, and measuring within-section layer thicknesses and material properties. In addition, the investigation addressed the potential effects of overlay thickness and overlay materials used (recycled and virgin asphalt) and the extent of surface preparation (minimum and intensive) on pavement performance. Destructive and nondestructive tests were conducted following the long-term pavement performance (LTPP) program test protocols. The main pavement distresses identified in the test sections included fatigue cracking, longitudinal cracking, transverse cracking, rutting, block cracking, and pumping. Based on the observations of the coring and trenching operations, most of the cracks were top-down cracks exhibiting high severity at the top and low severity at the bottom of the layer. Wheelpath rutting was observed in the overlay layer only, and virtually no rutting was detected in the lower layers. The maintenance activities (fog seals and crack sealing) applied over the years appeared to have reduced the propagation of fatigue and transverse cracks temporarily and did not significantly improve the postrehabilitation structural performance. While all sections performed well compared with the virgin asphalt overlay, the recycled overlay test sections exhibited the largest postrehabilitation rate of increase in roughness and rutting (with thinner overlays) over their monitoring period. Pavement deterioration was not associated with the base and subgrade layers. The extent of distress was also found to be associated with high binder content and air voids.

EXAMINATION OF CAUSES OF RUNWAY PAVEMENT FAILURE AND MEASURES AT NEW CHITOSE AIRPORT

Blistering of the runway surface course was found during a runway inspection at New Chitose Airport in June 2001. A more detailed survey revealed that water penetration has reduced the bearing capacity of both the surface course and the binder course below the joint, as well as the asphalt stabilization layer. Because of a working time restriction on the runway, the thick lift method, whereby asphalt is placed in a short time, was applied in combination with a large-grain asphalt mixture that can be placed at lower temperatures than usual. The study reports the causes of pavement failure and the results of measures against such failure.

Effect of Oxygen Pressure on Asphalt Oxidation Kinetics

The oxidation of asphalt is a major cause of pavement failure. At a given temperature and pressure, the asphalt oxidizes in two stages: (1) a rapid-rate period followed by (2) a long period with constant oxidation rate. The degree of oxidation that occurs in the constant-oxidation region is asphalt-dependent and varies with oxygen pressure and with temperature. Using pavement-temperature oxidation kinetics obtained for eight asphalts in this study, it has been determined that the activation energies for the constant-rate region are dependent on the oxygen pressure and can be related to the asphaltene composition of the asphalt. An oxidation kinetic model is developed to predict the rate of oxidation in the constant-rate region knowing an initial asphaltene composition variable for the asphalt.

Fracture Morphology and Fracture Toughness Measurement of Polymer-Modified Asphalt Concrete

Pavement distress occurs through a variety of mechanisms, but it is always controlled by the adhesive and cohesive performance of the asphalt binder. Although the causes of pavement failures are known, the precise mechanisms by which they occur remain to be understood. Observation of the fracture morphology of asphalt concrete can provide some information in this respect. The fracture morphology of asphalt concrete is dependent on the morphology of the binder. A network structure was observed in thin asphalt binder films and the fracture morphology and engineering properties of asphalt concrete were found to be dependent on the network morphology of the asphalt binder. Addition of polymers to asphalt binders causes changes in the nature of the network structure, and its effect can be qualitatively determined by characterizing the fracture morphology. Styrene butadiene styrene (SBS), styrene ethylene butylene styrene (SEBS), styrene butadiene rubber (SBR) latex and an epoxy-terminated reacting polyolefin (Elvaloy AM) were used in this study. A quantitative method to determine the effect of polymer modification on the fracture properties of asphalt concrete is the J-contour integral fracture toughness measurement. An experimental protocol to measure the critical J-integral fracture toughness ( J1 c) was developed and the low temperature (-10°C) J1 c values were determined for SEBS and Elvaloy AM-modified asphalt concrete at three different concentrations.

The kinetics of carbonyl formation in asphalt

AbstractThe oxidation of asphalt is a major cause of pavement failure. The low‐temperature oxidation kinetics of 14 asphalts are presented. At constant temperature and oxygen presure, asphalt oxidation occurs in two stages: (1) a relatively rapid‐rate period, followed by (2) a long period of constant rate. Activation energies for the constant‐rate region vary from 64 to 109 kJ/mol, and reaction orders relative to oxygen pressure vary from 0.25 to 0.61. This variation in activation energy and reaction order leads to skepticism regarding the present practices of evaluating road‐condition asphalt‐hardening rates at a single elevated temperature and perhaps at an elevated pressure. The asphalts occur in essentially two groups, one at high values of both activation energy and reaction order and the other at low values of each. The data indicate the existence of an isokinetic temperature near 100°C. The degree of oxidation that occurs during the initial rapid‐rate region varies inversely with the oxygen reaction order of the constant‐rate region.

Field Effects of Water Pumping Beneath Concrete Pavement Slabs

Water pumping beneath concrete pavement slabs is considered to be a major cause of pavement failure. The objectives of this work are to determine typical water pressures and velocities during pumping in the field as well as the effects of pressure, velocity, and thermal movement on erosion beneath slabs. The location of the water pumping is between the bottom of the concrete slab and the subbase. Field tests indicate that vehicle traffic produces high pressures beneath the second slab and suction pressures beneath the first, which induces water velocities in the opposite direction of vehicle motion. Field tests on Florida's Interstate 10 reveal pressure differences as high as 70 kPa, which produce velocities up to 0.9 m/s in the opposite direction of vehicle motion. Water pumping is more severe at the corner of the second slab and during upward thermal curling. Water movement may not be sufficient to cause subbase erosion based on this limited field data. The daily expansion‐contraction cycle is shown to ...

An application of satellite imagery for highway maintenance and rehabilitation in Niger

Abstract Recent studies in the Republic of Niger have demonstrated that information acquired from the interpretation of satellite imagery can play a significant role in the planning, management and implementation of highway maintenance or rehabilitation in developing countries. In addition to assisting overall alignment and design review, LANDSAT MSS data proved invaluable with respect to understanding physical causes of pavement failure and the engineering options required to overcome repetition of similar problems in the future.