Rut Depth Measurements Research Articles

MECHANICAL AND PERFORMANCE CHARACTERISTICS OF SEMI-RIGID MIX DESIGN WITH RECYCLED MATERIALS AND STANDARDIZATION OF RUT DEPTH MEASUREMENTS

Pavement industry requires substantial modifications in terms of materials. Stakeholders are in need to opt the solutions of semi-rigid design mix with recycled materials. Necessary evaluations in terms of experimental measures are initially required to represent characteristics properties. Moreover, the behavior to be assessed is rut depth measurements through the implications of wheel tracker apparatus and in accordance with prescribed standards. The mix with specified curing days is being differentiated through subsequent directions focusing choice of recycled materials. The paper presents a model to excel distinguished properties inclusive of the analysis for maintaining air voids, induction of grouting material and stability. The output-oriented data is justified within the enumerations of rut depths for grouted samples. It is analyzed for 25%, 30% and 35% air voids in conditioned to fresh and recycled aggregates. The deliberations are meant with 91 and 13 sample combinations of aggregates and hot mix asphalt respectively followed by the significant tests on bitumen and grouting material. It is observed that critical samples are passed in the configurations of rut depths when processed with reclaimed and construction waste materials at 35% voids. The research data entails its affectivity due to the uniqueness in superior model of current scenario.

Detection vehicle lateral offset overestimation on asphalt pavement rut depth measurement accuracy

Detection vehicle lateral offset overestimation on asphalt pavement rut depth measurement accuracy

Methods of Rut Depth Measurements on Forwarder Trails in Lowland Forest

Methods of Rut Depth Measurements on Forwarder Trails in Lowland Forest

A Case Investigation into Causes of Premature Rutting Failures in Rehabilitated Asphalt Pavements in Tanzania

Abstract Tanzania has faced high incidences of premature rutting failures on their asphalt pavements. Some pavements experienced failures within one to two years after construction/rehabilitation. The objective of this investigation was to identify the factors that contributed to the observed failures on five rehabilitated road sections on a national highway in Tanzania. Pavement temperature data collection, traffic surveys, visual inspection, rut depth measurements, and falling weight deflectometer tests constituted the main activities of the field investigation reported in this paper. The laboratory study included a visual assessment of cores extracted from the studied road sections to determine both physical and engineering properties, including density, stiffness, strength, aggregate shape properties, grading, and physiochemical tests on the recovered binders. The results of the study indicated that the degree and extent of rutting on the investigated road sections was rated as severe., i.e., rutting ranged from 38–138 mm on the five sections when compared to the acceptable threshold value of 15 mm for high volume roads in Tanzania. The elastic deflection results indicated that the underlying layers of the pavement system were generally in a sound condition, which validated the suggestion that the rutting observed was mostly confined to the asphalt concrete layers. Factors such as relatively high axle loads, poor asphalt mixes, and possibly inadequate quality control during construction and rehabilitation were suspected to contribute to the rutting on the sections. Practical measures recommended to the roads agency to avert future occurrences are provided in this paper.

Validation Technique for Heavy Vehicle Simulator Rut Measurement with Florida Laser Rut Meter

Abstract The performance of a pavement system is typically measured in structural and functional terms. Agencies often prioritize minimizing rutting as it indicates the mixture and structural inadequacy and can lead to safety concerns such as hydroplaning. Therefore, accurate rut depth measurement is critical to pavement management as well as to assess the performance of materials designed to resist rutting. To that measure, Florida Department of Transportation (FDOT) uses two heavy vehicle simulators (HVSs) as part of an accelerated pavement testing (APT) program to advance pavement research and implement new pavement materials, designs, and construction methods. Each HVS device is equipped with an on-board laser profiling system for rut depth measurement. To ensure accurate and reproducible rut depth measurements, a laser-based reference device was developed and constructed by FDOT to verify rut depth measurements made by both HVS devices during APT research studies. This article describes the rut depth reference device, the verification process, and data analysis methods used to validate the accuracy of the HVS devices.

Evaluation of Performance of Pavement Founded on the Reinforced Earth Sections along Outer Ring Road, Nairobi

There are no existing local design manuals and construction guidelines for reinforced earth structures in Kenya. The objective of this study was to evaluate the performance of the pavement found on reinforced earth sections along Outer Ring Road. The structural evaluation was determined from deflection measurements using Falling Weight Deflectometer (FWD), while the functional evaluation was by visual condition survey, roughness, and rut depth measurements. Classified traffic counts and axle load surveys were undertaken. It was established that the design traffic would be exceeded in year 10 after opening the road. The surface condition survey indicated that the pavement surface for the entire road was generally in good condition. The roughness rating for the entire road was rated "Good", while ten sections of reinforced earth embankment were rated "Fair". The characteristic rut depths on the reinforced earth sections were higher than the lane characteristic rut depth for the entire road. Three sections of the reinforced earth showed low severity, while the rest had no rutting. The PCI for the pavement on reinforced earth sections were lower than pavement on other sections of the road due to a higher International Roughness Index (IRI). The FWD deflections were higher on reinforced earth sections. It was found that the mean pavement moduli for surfacing and base, crack relief and subbase layers at reinforced earth sections were lower than for the pavement in other sections hence requiring thicker overlays. The overall residual life of the road was 17 years, while for the reinforced earth sections was 15 years. Based on the findings, monitoring of the traffic and performance of pavement on the reinforced earth embankments is vital for interventions to prevent premature pavement failure. There is a necessity to develop a design manual and construction guidelines for reinforced earth structures based on the local conditions in Kenya.

Unconventional and Simplified Approach towards Unpaved Roads: Application of Geosynthetics

Abstract: A field trial was carried out to investigate the performance of different unconventional geosynthetic materials in unpaved road construction over soft ground.The test site comprises of 25 m long, by 3 m wide test sections, built on a subgrade of undrained shear strength approximately 45 kPa . One isunreinforced and serves as a control section in the study, three sections includea geotextile, and one includes a geogrid. Each test section incorporated avariable thickness of sandy gravel base course material, between25 and 45 cmthick. They were loaded in sequence by a vehicle of standard axle load.Performance of the test sections was evaluated from measurements of rut depth, base course thickness, base course deformations, geosynthetic strain, and deformed profile of the geosynthetic, with increasing number of vehicle passes.The four geosynthetic materials used exhibited a broad range of stiffness and material properties ,but the general performance of the four reinforced sections was similar on the base course layers. On contrary thinner subgrades showed a significant difference between the geosynthetics Keywords: Geo-synthetic materials, geo-textile, geo-grid, unpaved road.

Feasibility of Mobile Laser Scanning towards Operational Accurate Road Rut Depth Measurements.

This paper studied the applicability of the Roamer-R4DW mobile laser scanning (MLS) system for road rut depth measurement. The MLS system was developed by the Finnish Geospatial Research Institute (FGI), and consists of two mobile laser scanners and a Global Navigation Satellite System (GNSS)-inertial measurement unit (IMU) positioning system. In the study, a fully automatic algorithm was developed to calculate and analyze the rut depths, and verified in 64 reference pavement plots (1.0 m × 3.5 m). We showed that terrestrial laser scanning (TLS) data is an adequate reference for MLS-based rutting studies. The MLS-derived rut depths based on 64 plots resulted in 1.4 mm random error, which can be considered adequate precision for operational rutting depth measurements. Such data, also covering the area outside the pavement, would be ideal for multiple road environment applications since the same data can also be used in applications, from high-definition maps to autonomous car navigation and digitalization of street environments over time and in space.

Construction, instrumentation and field performance of geogrid-reinforced unpaved roads

A research study involving full-scale unpaved road test sections was carried out to investigate the performance of unpaved roads reinforced with geogrids. Ten test sections were constructed with two different base course thicknesses. Three biaxial geogrids of different tensile stiffness and one geogrid with triangular aperture were evaluated. Geogrids were placed at the subgrade–base course interface. The sections were instrumented for measuring road response to traffic loading. Traffic loading was provided by a single-axle dump truck. Field measurements of rut depth and surface deformation were recorded at selected traffic intervals. An analysis of the measured performance data indicated that the geogrids effectively reduced surface rutting and improved the performance of unpaved thin base layers and the benefit became more pronounced when a stiffer geogrid was used. The results suggested reductions in the thickness of the base layer by using geogrids of up to 18%. The improvement by geogrids was shown to be less for increasing base layer thickness. In addition, the ability of the design procedure by Giroud and Han to predict rutting performance using the test section parameters as design inputs was assessed. The results indicated that the method underpredicted the required base thickness to support the applied traffic loads.

Development of Bonded Natural Stone Pavement Using Ultra-Rapid-Hardening Mortar

Bonded natural stone pavement has been typically used in historical neighborhoods to satisfy functional and architectural aesthetic standards. Despite its advantages, it has been barely applied to places for heavy traffic volume or high travelling speed because of various structural failures in joints and bedding courses. Ultra-rapid-hardening mortar for natural stone pavement was considered as an alternative to minimize these failures. The objective of this study is to develop bound stone pavement using the ultra-rapid-hardening mortar for high traffic volume and evaluate throughout by carrying out material tests, plate load test, accelerated pavement test (APT), and falling weight deflectometer (FWD) test. For the tests, four types of pavements, asphalt, concrete block, and two bound stone pavements, were produced in a testing facility. The bearing capacity of the sub-base course, which was asphalt and concrete, showed values 1.62 and 2.64 times higher than deemed satisfactory. Additionally, rut depth was measured using a transverse profile logger during the APT test and the test was terminated at 1.97 million cumulative equivalent single axle loads (ESALs). In the rut depth measurements, the deepest deflection (16.0 mm) was made in the asphalt pavement and the depth of the concrete block pavement was 4.5 mm. Vertical displacements of 3.0 and 1.5 mm were obtained in stone pavements A and B, respectively. The maximum pavement vertical deflection response was recorded at 0, 0.4, and 1.97 million ESALs. The response results revealed that they were influenced by the material types of either bedding or sub-base courses. With these outcomes, it would be possible to apply the baseline data for designing rigid small element pavement for heavy traffic volume or high travelling speed roads.

Assessing extraction trail trafficability using harvester CAN-bus data

ABSTRACT Modern forest machines with a Controlled Area Network (CAN)-bus managed diesel engine and hydrostatic transmission can continuously measure power expended in traveling. At a constant speed on level ground, the power is expended in overcoming motion resistance, which is directly related to wheel sinkage and hence to site trafficability. In cut-to-length timber harvesting, the harvester precedes the forwarder on the site, making it feasible to utilize the harvester to collect data on site trafficability to produce a trafficability map for the forwarder. CAN-bus trafficability mapping was tested with an 8-wheeled Ponsse Scorpion King harvester and an 8-wheeled Ponsse Elk forwarder instrumented for collecting transmission power expenditure, in addition to appropriate available CAN-bus information. Trafficability was also mapped based solely on momentary engine power in order to eliminate the need for additional pressure transducers. The CAN-bus data showed good results for mapping site trafficability when compared to soil penetration resistance and harvesting machinery wheel rut depth measurements. Assessing harvester rolling resistance using CAN-bus data offers an interesting possibility to map harvesting site trafficability also in Big Data scale. Since modern harvesters are practically ready for indirect power recording, the additional cost of fully automated and comprehensive trafficability mapping as part of operative forestry is negligible.

Rut depth measurement of an asphalt pavement from its original profile

ABSTRACT Various manual and automated methods are used for the measurement of rut depth of an asphalt pavement. It is observed that different methods of rut depth measurement give different values of rut depth even for the same pavement profile. It is also observed that while using LTPP database, in some cases, the reported rut depths do not increase monotonically with time as one would typically expect. The present work explores possible reasons for these discrepancies. Subsequently, suggestion is made to measure the rut depth with reference to the original profile of the pavement. This resolves the issues related to the discrepancies with the rut depth measurement.

Determining the Relationship Among Hamburg Wheel-Tracking Test Parameters and Correlation to Field Performance of Asphalt Pavements

The Hamburg wheel-tracking test (HWTT) is commonly used to evaluate the rutting resistance and moisture susceptibility of asphalt mixtures. Over the years, different test parameters have been proposed, including the traditional ones specified in AASHTO T 324 and several alternatives developed by asphalt researchers. This study was undertaken to refine the HWTT method toward enhancing its implementation as part of balanced mix design specifications for asphalt mixtures. A HWTT database was developed including test results of over 70 mixtures with a wide range of mixture components and production parameters. Data analyses were conducted to examine the relationships among various HWTT parameters, determine their correlations to field performance data, and estimate the within-laboratory repeatability of the test results. Two alternative rutting parameters, rutting resistance index ( RRI) and corrected rut depth ( CRD), were found to be advantageous over the traditional parameters of total rut depth ( TRD) and creep slope ( CS). RRI allows for direct comparison of results with different termination points, and CRD isolates the rut depth resulting from permanent deformation from that caused by stripping. Among all the rutting parameters, RRI had the best correlation to field rut depth, followed by CS, CRD, and TRD. Receiver operating characteristic analysis was conducted to determine the correspondence between HWTT results and pavement field performance related to moisture susceptibility. The analysis identified 9,000 passes as the best criterion for stripping inflection point and 2,000 passes for the alternative moisture susceptibility parameter, stripping number. Finally, the within-laboratory repeatability of HWTT rut depth measurements was determined.

Road Rutting Measurement Using Mobile LiDAR Systems Point Cloud

Road rutting caused by vehicle loading in the wheel path is a major form of asphalt pavement distress. Hydroplaning and loss of skid resistance are directly related to high road rutting severity. Periodical measurements of rut depth are crucial to maintenance and rehabilitation planning. In this study, we explored the feasibility of using point clouds gathered by Mobile LiDAR systems to measure the rut depth. These point clouds that are collected along roads are usually used for other purposes, namely asset inventory or topographic survey. Taking advantage of available clouds to identify rutting severity in critical pavement areas can result in considerable economic and time saving and thus, added value, when compared with specific expensive rut measuring systems. Four different strategies of cloud points aggregation are presented to create the cross-section of points. Such strategies were established to improve the precision of individual sensor measurements. Despite the 5 mm precision of the used system, it was possible to estimate rut depth values that were slightly inferior. The rut depth values obtained from each cross-section strategy were compared with the manual field measured values. The cross-sections based on averaged cloud points sensor profile aggregation was revealed to be the most suitable strategy to measure rut depth. Despite the fact that the study was specifically conducted to measure rut depth, the evaluation results show that the methodology can also be useful for other mobile LiDAR point clouds cross-sections applications.

Real time rut profile measurement in varying terrain types using digital image correlation

An important parameter in terramechanics is the rut depth produced when a vehicle traverses deformable soil. The rut depth provides a measure of vehicle tractability as well as the impact on the environment. Rut depth is not uniform on natural terrain and typically only a few manual points are measured. Synchronizing rut depth with other measurements is also problematic.This paper investigates the feasibility of using cameras to measure 3D terrain profiles from which a single rut depth measurement is obtained. Tests were performed on different vehicles, for various dynamic vehicle manoeuvres, over varying terrains including sand, mud, grassland, snow and ice. Results were validated using the traditional stick ruler method.Measurement frequencies of 58 Hz were obtained using affordable commercially off the shelf computational hardware and dedicated software. Determining whether a vehicle can traverse a terrain can significantly improve the vehicle mobility. Therefore, real time measurements of rut depth can be used to determine the mobility of vehicles in off-road conditions that can change rapidly due to environmental conditions e.g. rain or snow. The techniques described can assist in gathering terrain and vehicle mobility data that can be used directly to assist the driver in making safety related decisions.

Objectification of Public Bus Stop’s Pavement Surface Morphology

Abstract The article deals with the road pavement surface morphology objectification in term of the surface unevenness degradation during the life cycle of bus stop pavements. The article presents the results of long-term rut depth measurements performed during 25 years on selected bus stops which were intended to determine correlation dependences of pavement rut depth on a number of design axles. The article also presents different methods for rut depth measurements including the straightedge test, Profilograph GE, TRIMBLE CX, and dynamic Road Scanner.

Critical assessment of the impact of vehicle wandering on rut depth measurement accuracy using 13-point based lasers

Accurate rut depth measurements have a substantial impact on the reliability of pavement performance evaluation, maintenance and rehabilitation (M&R) determination, and M&R funding allocation. To measure pavement rutting, China commonly uses 13-point based lasers. However, based on the 13-point lasers configuration, errors in rut depth measurement are inevitable if the vehicle on which the lasers are mounted wanders. Existing studies have not considered the impact of vehicle wandering on rut depth measurement accuracy and the relationship between rut shape and offset error. In this paper, 10 representative transverse profiles, including both symmetrical and non-symmetrical rut shapes with low and high severity levels of rut depths, were selected from 1100 actual transverse profiles (a 220-m rutting section from a 1.2 km roadway) that were acquired using a 13-point laser bar to simulate the impact of 5 different degrees of vehicle wandering on rut depth measurement accuracy. Results show that vehicle wandering could result in rut depth measurements error of the absolute and relative by as much as 6.4 mm and 29%, respectively. In-depth analyses show that the degree of rut depth measurement error is impacted substantially by the rut shape characteristics, including the position, slope, depth, and pattern of rut shapes (symmetrical and non-symmetrical), and the corresponding direction (right or left) of a vehicle's wandering. For example, a vehicle wandering in the direction opposite to the dominating/severe rut depth will result in a large rut depth measurement error. The contributions of this paper include quantifying the impact of vehicle wandering on rut depth measurement accuracy and identifying the factors, including the rut shape characteristics and characteristics of vehicle wandering, that might reduce rut depth measurement accuracy.

Wheel rut measurements by forest machine-mounted LiDAR sensors – accuracy and potential for operational applications?

ABSTRACT Soil rutting caused by forest operations has negative economic and ecological effects and thus limits for rutting are set by forest laws and sustainability criteria. Extensive data on rut depths are necessary for post-harvest quality control and development of models that link environmental conditions to rut formation. This study explored the use of a Light Detection and Ranging (LiDAR) sensor mounted on a forest harvester and forwarder to measure rut depths in real harvesting conditions in Southern Finland. LiDAR-derived rut depths were compared to manually measured rut depths. The results showed that at 10–20 m spatial resolution, the LiDAR method can provide unbiased estimates of rut depth with root mean square error (RMSE) < 3.5 cm compared to the manual rut depth measurements. The results suggest that a LiDAR sensor mounted on a forest vehicle can in future provide a viable method for the large-scale collection of rut depth data as part of normal forestry operations.

Influence of computation algorithm on the accuracy of rut depth measurement

Rutting is one of the dominant pavement distresses, hence, the accuracy of rut depth measurements can have a substantial impact on the maintenance and rehabilitation (M & R) strategies and funding allocation. Different computation algorithms such as straight-edge method and wire line method, which are based on the same raw data, may lead to rut depth estimation which are not always consistent. Therefore, there is an urgent need to assess the impact of algorithm types on the accuracy of rut depth computation. In this paper, a 13-point-based laser sensor detection technology, commonly accepted in China for rut depth measurements, was used to obtain a database of 85,000 field transverse profiles having three representative rutting shapes with small, medium and high severity rut levels. Based on the reconstruction of real transverse profiles, the consequences from two different algorithms were compared. Results showed that there is a combined effect of rut depth and profile shape on the rut depth computation accuracy. As expected, the difference between the results obtained with the two computation methods increases with deeper rutting sections: when the distress is above 15 mm (severe level), the average difference between the two computation methods is above 1.5 mm, normally, the wire line method provides larger results. The computation suggests that the rutting shapes have a minimal influence on the results. An in-depth analysis showed that the upheaval outside of the wheel path is a dominant shape factor which results in higher computation differences.

Evaluation of AASHTO T 324 Hamburg-Wheel Track Device test

The Hamburg Wheel-Track Device (HWTD) test has recently gained popularity among many state highway departments of transportation (DOTs) for use in hot mix asphalt (HMA) moisture sensitivity evaluation. In this paper, suggestions are presented to improve and provide more consistent and representative results for this test as described in AASHTOT324 – Hamburg Wheel-Track Testing of Compacted Hot Mix Asphalt (HMA). In the AASHTOT324 specification, either a cylindrical or a slab specimen can be tested. Use of a two-dimensional micromechanics finite element (2D-MMFE) analysis has demonstrated significant gap/bonding and specimen shape effects on HWTD test results for the cylindrical specimen setup. In addition, the analysis suggests the best method for defining the “rut depth” to ensure consistent results between two specimen setups. Results of this study have concluded that: (1) slab specimens can provide more reliable test results due to larger size and uniform geometry; (2) two cylindrical specimens (cores) should be glued together to prevent localized failure due to larger peak maximum principal strains when there is no bonding; (3) measurements of average rut depth should be collected from stations near the centers of cylindrical specimens to keep the specimen shape effects to the lowest possible level; and, (4) an agency should not allow both specimen setups to be used interchangeably in the HWTD specifications. The investigation also suggests that the average rut depth evolution curve fitted using a three-stage Weibull approach can define the number of passes to failure and define the stripping initiation point (SIP) better than the visually determined SIP.