Wheel Track Research Articles

Predicting a Model for Modified Asphalt Cement Rutting Parameters

This paper aims to investigate the relationship between the Superpave rutting parameter of asphalt (G﹡/sin δ) by conducting Dynamic Shear Rheometer (DSR) tests with the rut depth values obtained by the wheel track device. The twenty asphalt mixtures have been prepared with twenty types of unmodified asphalts and Polymer-Modified Binders (PMBs). SBS was used to produce PMBs. The twenty base and modified asphalts have been used to prepare asphalt paving mixtures required to conduct wheel track tests. The predicted model of asphalt mixtures rut depth related to asphalt rutting parameter (G﹡/sin δ) values has been founded. Besides, the minimum limits of (G﹡/sin δ) of aged asphalt have been gotten as 3.25 kPa for Iraqi asphalt cement.

Assessment of performance of hot mix asphalt contained various types of mineral fillers and newly polymer modified bitumen

This research aims to test various types of fillers such as (limestone dust, rice husk ash and ordinary Portland cement) and examine their influence on the performance of the asphalt mixture containing Polymer Modified Bitumen (PMB) binder. The research includes designing a regular reference mix for the purposes of comparison and designing several asphalt mixtures with various percentage (25, 50, 75 and 100) % RHA & OPC as mineral filler and PMB. Several tests were conducted to evaluated the mechanical characteristics and performance of Hot Mix Asphalt (HMA) such as Marshall stability, Indirect Tensile Strength (ITS), creep compliance and wheel track test. The results of investigation revealed that, the using of PMB significantly improved the mechanical characteristics and performance of HMA. The results of creep compliance demonstrated that the replacement of conventional MF with 50% RHA or 50 % OPC leads to decrease creep compliance values of HMA contained PMB by 68% and 64 % respectively compared with control mix. Also, for the same percentages of replacement and PMB, the rut depth values decreased by 64% and 48 % respectively compared with the reference mixture.

Research on temperature-magnetic properties based on metal magnetic memory testing technology

during the running of high-speed railway, the vibration and friction between wheel set and track will cause the temperature rise between wheel set and track. The metal magnetic memory detection technology is used to detect the small fault of wheel set, and the temperature will have a certain impact on the magnetic memory signal. In order to study the quantitative relationship between temperature and magnetic memory signal, the temperature magnetic property of 25CrMo4 material is proposed in this paper. Through the temperature magnetic experiment and simulation analysis of the material specimen, it is concluded that when the temperature is lower than Curie point, the magnetic flux leakage of the sheet is basically stable. The value in tangential direction is 130A/m, and the value in normal direction is 0A/m. When the temperature reaches Curie point, the value of the tangential direction changes to 169.9 A/m, and the normal direction is still 0A/m; And the temperature magnetic numerical simulation curve is constructed, which provides the basis for carrying out magnetic signal to material small fault under coupling load, and provides the basis for non-destructive testing.

Evaluation of performance of hot mix asphalt contained various sizes of Reclaim asphalt pavement and polymer modified Bitumen

The present investigation intends to investigate the performance of Hot Mix Asphalt (HMA) included Reclaim Asphalt Pavement (RAP) and Polymer Modified Bitumen (PMB) binder prepared with Novolac (phenol–formaldehyde solid resin)polymer. In order to assess the mechanical properties and performance of HMA with various RAP contents, several laboratory tests such as Marshall tests, indirect tensile strength testing, moisture damage evaluation, creep compliance test, and wheel track test was performed. The substitution was conducted in two stages: the first stage includes replacing the coarse aggregate with RAP up to 40percent with an increment of 10percent and the second stage includes the substitution of fine aggregate with the same percentages. The PMB binder was prepared by testing several mixes with various percentages of Novolac and its cross-linking agent (Hexamine). The findings of experimental work showed that the use of PMB binder significantly improves the mechanical properties and performance of HMA. Also, it shows that the substitution of coarse aggregate with RAP produces a substantial improvement in mechanical properties and performance of HMA compared with the substitution of fine aggregate or with control mix.

Soil structure response to field traffic: Effects of traction and repeated wheeling

Soil compaction caused by the use of heavy agriculture machinery in non-optimal soil conditions hampers crucial soil functions. Tyre inflation pressure and wheel load are well-known key drivers of compaction. The effects of traction and repeated wheeling are, however, not yet fully understood but may be of critical importance. We aimed to quantify the effects of traction and repeated wheeling on some soil structural properties independently in a compaction experiment conducted on a sandy loam at a soil water content near field capacity, using a tractor-trailer combination at two loads. The trailer was used in ‘standard’ and ‘offset’ steering modes, the latter referring to the mode in which measurements could be taken for the pass of a single towed and thereby passive trailer wheel (with one, two, three and six wheel passes). Penetration resistance was measured to 0.71 m depth and 100-cm3 soil cores were collected around 0.16 m depth for structural property measurements. In the offset steering mode, the measurements were made in the tractor tracks to investigate the effect of traction and in the trailer’s wheel track to investigate the effect of repeated wheeling (at 6.0 Mg static wheel load). The measurements were also collected for the standard steering configuration with the high towed load and from reference plots. Measurements on the soil cores comprised bulk density, porosity, and air permeability. We found a clear effect of traction on deformation of some soil structural properties, with no significant effects of the low drawbar pull but with substantial effects of the high drawbar pull. Reductions in air permeability and specific permeability were significant (89 % and 83 %, respectively) and indicated a densification and homogenisation of the soil. The effect of repeated wheeling was gradual and reasonably well explained by a linear fit to the number of wheel passes. After six passes with the passive wheel caused some soil structural properties to differ significantly from the reference soil, and resulted in approximately similar levels of bulk density, porosity, air permeability and specific permeability as the tractor with high drawbar pull. Still, the deformation was stronger for the single pass of the tractor with the high drawbar pull than for six repeated wheeling of the passive trailer wheel. These results highlight the substantial effect of traction on soil compaction. Yet, the mechanisms causing this deformation remain speculative until the propagation of horizontal stress through the soil profile is better understood.

Dynamic response analysis of the brake disc of a high-speed train with wheel flats

To study the vibration characteristics and stress state of brake discs during vehicle operations, a spatial trailer car-track coupled dynamics model was developed with the consideration of flexible brake disc. In the model, the components of a trailer car are considered as rigid bodies. Flexible models of the brake disc and wheelset were established using the finite element method. The trailer car-track coupled dynamics model is validated using experimental test results. The effects of wheelset flexible deformation on the dynamic properties of brake discs were investigated with the excitations of track irregularity and wheel flats. Furthermore, the brake disc was systematically evaluated and discussed under the condition of wheel flats in the coupled dynamics system. The results indicate that compared to rigid wheelsets with wheel flats, flexible wheelsets can cause the brake disc to vibrate more severely with higher stress. The severe vibration and high stress state of the brake disc could cause it to crack in the region near the bolts. The established dynamics model can be further developed and employed to assess the dynamics of the brake systems of high-speed trains.

Investigation the effect of newly used polymer modified bitumen on the performance of hot mix asphalt containing reclaimed asphalt pavement

The current research focuses on investigating the effect of using reclaimed asphalt pavement (RAP) on performance of hot mix asphalt (HMA) prepared with polymer modified bitumen (PMB) binder. This PMB used for the first time with HMA contained RAP. The mechanical properties and performance of HMA were assessed using several standard tests including Marshall, indirect tensile strength, creep compliance, and wheel track test. The RAP replacement was conducted up to 70% of total aggregate in HMA with an increment of 10%. The results of investigation showed, that the use of PMB binder prepared by addition novolac (phenol formaldehyde solid resin) and hexamine to conventional bitumen, significantly improved the performance of HMA contained RAP. Also, the optimum percentage of RAP replacement was found to be 50% of total aggregate in HMA. For this level of replacement, the rut depth reduced up to 38% of its original value.

Physical-Hydraulic Quality Indicators of soils with different years of management under Pinot Noir (Vitis vinifera L.)

The present study aimed to evaluate the physical-hydraulic quality of soils with different years of management after planting Vitis vinifera L. cv. Pinot Noir. Areas with 4, 9 and 16 years of cultivation were evaluated, at depths of 0.0-0.10, 0.10-0.20, 0.20-0.30, 0.30-0.40, 0.40-0.50 and 0.50-0.60 m, in three replicates, in the wheel track (WT), between wheel tracks (BWT) and in the planting row (PR), were analyzed. The physical quality indicators analyzed were bulk density, macroporosity, microporosity, total porosity. Soil water infiltration was also analyzed at these positions, by the method of double concentric rings, both with 30 cm height, and diameters of 50 cm in the outer ring and 25 cm in the inner ring, which were buried 15 cm deep into the soil and filled with water. Soil management in the different periods of planting resulted in a heterogenous soil compaction in the vine interrows. The position between wheel tracks (BWT) has a higher infiltration rate, regardless of the vineyard management time.

Influence of high moisture content on road pavement structure: A Polish case study

Communication infrastructure is one of the most important criteria determining the comfort and quality of life in a given country, as well as an important indicator helping to determine the pace of its economical growth. The main objective accompanying the development of the road network is to ensure the required durability of the pavement structure. Undoubtedly, one of the factors that shorten the life of the road pavement and cause its premature damage is the increased moisture content in the pavement structure, in particular in unbound granular layers. The article presents a case study on the accelerated degradation of a section of state-importance road located in the southern part of Poland, where a problem of increased moisture content in the road pavement structure occured. The research part shows the results of measurements of the transverse evenness of the pavement, monitoring of the groundwater table level and measurements of pavement deflection using Falling Weight Deflectometer. The conducted research and observations showed that the pavement on the selected road section worked permanently in high moisture conditions, where the groundwater table stabilized at an average level of 30–60 cm below the pavement surface. During the observation period, an increase in the rut depth in the right wheel track was noticed, reaching a value of 3.2 mm. In addition a significant development of damage visible on the wearing course was observed. Based on the results of defelection measurements, a back-calculation analysis was performed, which allowed to obtain estimated resilient moduli values of subsequent pavement layers and the subsoil. Resilient moduli values of the unbound subbase and the bituminous layers were significantly lower than the expected values, which was related to the high moisture content in the road pavement structure.

Fatigue Performance of Steel-Concrete Composite Continuous Box Girder Bridge Deck

The fatigue performance of the bridge deck significantly affects the safety and durability of the overall steel-concrete composite beam bridge. Based on the vehicle flow information of the highway within 10 years, the fatigue performance of a two-way four-lane steel-concrete composite continuous beam bridge deck is studied in this research. The results indicate that the effect of the wheel track position is negligible for two-way four-lane bridge when the wheel track sways laterally, and the fatigue stress of bridge deck concrete is the most unfavorable while the loading position is 7.0 m away from the bridge center line. The fatigue damage decreases by 30%–40% when the centerline of the lane deviates from the most unfavorable stress position by 1 m. The punching fatigue of the concrete is more sensitive to the changes in slab thickness, and the thickness of the deck concrete slab is recommended to be ≥35 cm.

Railway wheel tread damage and axle bending stress – Instrumented wheelset measurements and numerical simulations

ABSTRACT A combination of instrumented wheelset measurements and numerical simulations of axle bending stresses is used to investigate the consequences of evolving rolling contact fatigue (RCF) damage on a passenger train wheelset. In a field test campaign, stresses have been monitored using a wheelset with four strain gauges mounted on the axle, while the evolution of wheel tread damage (out-of-roundness) has been measured on regular occasions. The strain signals are post-processed in real time and stress variations are computed. Based on a convolution integral approach, the measured wheel out-of-roundness has been used as input to numerical simulations of vertical dynamic wheelset–track interaction and axle stresses. Simulated and measured axle stresses are compared for cases involving combinations of low or high levels of rail roughness and the measured levels of RCF damage. The study enhances the understanding of how wheel tread damage and track quality influence axle stress amplitudes.

Evaluation of the effectiveness of vehicle roll stability control (RSC) for high center of gravity light passenger vehicles in Australasia

Objective Rollover crashes, which occur when the vehicle’s side or roof makes impact with the ground, present particularly serious injury risk. Higher rollover risk has been found for high riding vehicles – those with a relatively high center of gravity compared to the width of the wheel track. Electronic Stability Control (ESC), which automatically applies brakes to individual wheels and reduces engine power to help drivers regain control when traction is lost, has been shown to be effective in preventing a proportion of rollovers. A newer safety technology, Roll Stability Control (RSC), uses similar technology aimed specifically to reduce rollover risk. This study sought to estimate rollover crash rates associated with the fitment of RSC compared to non-fitment for high center of gravity (CG) light passenger vehicles using an induced exposure analysis. Methods Police-recorded Australasian crash data were studied for the years 2008-2017. A quasi-induced exposure analysis was restricted to vehicles already equipped with ESC as vehicles fitted with RSC always have ESC fitted. Rollover risk associated with RSC fitment was assessed, controlling for year of crash, speed limit at crash location, year of vehicle manufacture, vehicle market group, driver age, driver gender and jurisdiction identifier. Results The analysis found a statistically significant rollover risk ratio of 0.76 (95% CI 0.62-0.93), representing a 24% reduction in rollover risk, associated with RSC fitment for vehicles manufactured between 2008 and 2017. Analysis by particular market groups found significant risk ratio reductions for commercial utilities and large SUVs, but not for the other high CG market groups individually. Conclusions These results suggest that RSC is a highly effective safety feature for high CG vehicles. Fleet data from Australia and New Zealand showed declining rates of RSC fitment over recent years for SUVs, meaning the potential road safety benefits of the technology are not being fully realized.

Effects of speeds and weights of travelling vehicles on the road surface temperature

It is important to predict the fatigue conditions of in-service roads for monitoring the state of internal pavement layers, planning the routine maintenance services and for ensuring the safety of travelling vehicles. Among various factors, the frictional heat generated by the tires of moving vehicles is considered to be an important factor causing such a distress in in-service roads. Because of this frictional heat, the temperature of wheel tracks is slightly warmer than other parts of the pavement, thereby, causing a non-uniform distribution of road surface temperature (RST) that may be responsible for developing cracks and subsequent increase in permeability of existing roads. In this study, the effect of travelling vehicles on the RST was investigated by using an infrared (IR) camera in an in-service road. In order to know the actual distribution of temperature, the RSTs were compared between the wheel track of each lane and in-between lanes. Then, the effect of speeds and weights of travelling vehicles on the RST was investigated. A bridge weigh-in-motion (BWIM) system using MEMS accelerometers was utilized to identify the speed and weight of a travelling vehicle. A strong correlation was observed between the rise of RST of wheel tracks due to the friction with the speeds and weights of travelling vehicles. The rate of increase in surface temperature was observed to be higher for the higher axle vehicles. Additionally, an influence of ambient air temperature was observed on the relationship between the rise of RST with the speeds and weights of travelling vehicles.

Effect of aggregate structure on load-carrying capacity and deformation resistance of porous asphalt concrete based on discrete-element modelling

ABSTRACT Porous asphalt concrete (PAC) constitutes large air voids and coarse aggregate, forming a unique aggregate structure. The open pore structure is advantageous in creating space for stormwater runoff to infiltrate into an underground basin and reduce tyre-road noise. However, this aggregate structure compromises the load-carrying capacity and deformation resistance of the mixture. Achieving balance between permeability and bearing capacity of PAC has been a major concern. This study evaluates effects of the aggregate structure on bearing capacity and the deformation resistance of PAC. Gradation-based framework was first applied to examine different gradations of PAC. Discrete-element models of PAC with varying gradations were developed to evaluate its performance and characteristics of aggregate skeleton. A laboratory wheel track test was conducted to validate findings from the DEM analysis. It was found that gradation that meets the interlock check of the framework produced a mixture with optimal performance. More coarse aggregate provides additional strength but lacks sufficient smaller-sized particles to form a new skeleton when it breaks down. More fine aggregate diminishes the load-carrying capacity and deformation resistance of the mixture as no stable skeleton could be formed.

Impact of Geometry of Toothed Segments of the Innovative KOMTRACK Longwall Shearer Haulage System on Load and Slip during the Travel of a Track Wheel

Longwall shearers operating in the underground mine workings move along the longwall face along the conveyor troughs. The haulage system, which is made up of two kinematic pairs in the form of track wheels installed in shearer movers, cooperating with the toothed route built in the conveyor’s throughs, is responsible for moving the shearer. The currently used solutions of longwall shearers’ haulage systems do not ensure proper cooperation of the track wheels with toothed segments, which results in failures and breakdowns in the operation of the longwall systems, causing significant financial losses. Rigid solution of the gear components used is the reason. The solution of the flexible toothed segment, allowing it to adapt to the longitudinal and transverse curvature of the AFC (armored face conveyor) route during cooperation with the track wheel, was developed as part of the research project jointly implemented by KOMAG Institute of Mining Technology, AGH University of Science and Technology, Łukasiewicz Research Network–Cracow Institute of Technology, Specodlew Innovative Foundry Company and Polish Mining Group Inc., co-financed by the European Regional Development Fund (contract no. POIR.04.01.04-00-0068/17). The general design and principle of operation of the suggested KOMTRACK system is given. The results of the comparative simulations and analyses are presented. The load and slip values during the cooperation of the track wheels with the standard and new suggested toothed segment were estimated. The effectiveness of cooperation in the shearer movement along a disturbed conveyor route was also compared.

Laboratory and Field Evaluation of Pre-Treated Dry-Process Rubber-Modified Asphalt Binders and Dense-Graded Mixtures

Pre-treatment of ground tire rubber is emerging as a popular method to incorporate rubber particles in dense-graded asphalt mixtures. This study investigates the effects of a chemically engineered Dry-Process Ground Tire Rubber (DP-GTR) modification in asphalt binders and mixtures. The DP-GTR is comprised of rubber particles measuring 400 to 600 µm in diameter (minus #30 mesh) coated with a non-elastomeric liquid. No change in aggregate gradation is necessary in DP-GTR modification of asphalt mixtures. In this study, the effects of DP-GTR modification on binder properties were measured by dynamic shear rheometer, Multiple Stress Creep and Recovery (MSCR), and bending beam rheometer tests. Additionally, mixture properties measured by three cracking tests: Disk-shaped Compact Tension (DC[T]) test, Illinois Flexibility Index, and indirect tensile asphalt cracking test and one rutting test (Hamburg wheel track test) were evaluated. Results showed: (a) 10–12°C bump on binder high temperature performance grade with 10% DP-GTR modification by weight of binder; (b) improvement in non-recoverable compliance in MSCR test indicated higher rut resistance; (c) increase in DC(T) fracture energy at low temperatures; (d) decrease in rut depth; and (e) decrease in flexibility index and cracking test index. Field performance of the chemically treated DP-GTR sections located in different states was examined to address discrepancies observed in the cracking tests. The cracking and rutting performance of all the field sections was good-to-excellent, suggesting that some of the currently popular simple cracking tests may not be able to properly assess the cracking resistance inherent in GTR-modified asphalt mixtures.

TRAFFIC VOLUMES TEST OF AIRPORT RUNWAY


 
 
 Currently, airport pavement design only considers the different horizontal standard deviation at the end and the middle of the runway, which had ignored the longitudinal distribution of airport runway traffic volume (ARTV). Especially for short take-off and landing aircraft, the take-off and landing distribution are not full of the whole runway. In allusion to the characteristics of ARTV, this paper developed a test system for the wheel track distribution and conducted a test of a short take-off and landing aircraft. Based on the statistics and analysis of test results, the horizontal and longitudinal distribution statistical laws of ARTV were obtained. At last, the longitudinal passage factor was proposed, and the planar distribution model was established to evaluate the ARTV at each point of the runway. By comparison with current design specifications, it is indicated that the pavement thickness will be designed more conservative without considering the planar distribution of traffic volumes.
 
 

Research on Maintenance Management of Flexible Pavement Based on C-LTPP

Based on the Canadian Long-Term Pavement Performance (C-LTPP) data, this paper chooses the road performance related data as variable factors. According to the Dipstick detection results, the characteristic values such as rut depth, wheel track width and cross section area are extracted to describe the rutting. This paper established the relationship between the pavement rutting and the cumulative service time, determined the rutting evaluation index, and proposed the pavement maintenance time threshold. Comparing the flexible layer overlay repair schemes used in various test points, it provides a reference for the pavement performance management decision-making and the road repair scheme design after repair.

Peningkatan Effisiensi Tenaga Kerja pada Lintasan Assy Wheel dengan Metode Line Balancing Ranked Positional Weight

<em>In the production of motorcycles at PT XYZ, there are various manufacturing processes and one of them is the Assy Wheel process. The Assy Wheel process for the K93X type performed on PT XYZ has a fairly low track efficiency. This happens because there are some unbalanced work stations where the conditions are quite detrimental to the company, so they need to be minimized or eliminated. One way to minimize unbalanced work stations is by balancing work tracks with the RPW (Ranked Positional Weight) method. This method is done by making a precedence diagram, determining the weighting of positions for each work element, sorting work elements by ranking position, placing work elements on a work station, placing the remaining time on an operation in the next sequence at the work station. After the analysis process is carried out on the Assy Wheel Track, there is a work element at the work station that needs to be changed and balanced. Work elements are combined at the next work station so that the track efficiency increases from 74% to 95%, the number of work stations and labor is reduced from four to two</em>

Performance properties of WMA modified binders and asphalt mixtures containing PPA/SBR polymer blends

The performance properties of asphalt binders and mixtures can be enhanced utilizing several modifiers, including; Poly Phosphoric Acid (PPA), Warm Mix Asphalt (WMA) modifiers, and Styrene–Butadiene Rubber (SBR). The current study evaluated the effect of PPA and WMA contents on rheological behavior of SBR modified binders and SMA mixtures. The modified binders were subjected to rotational viscosity, Dynamic Shear Rheometer, and Bending Beam Rheometer, Multiple Stress Creep Recovery (MSCR), and Linear Amplitude Sweep (LAS) tests. The SBR/PPA and SBR/PPA/WMA modified mixtures were subjected to Indirect tensile strength (ITS), dynamic creep, resilient modulus ( Mr), wheel track, and four-point beam fatigue (FPB) tests. To analyze the data, two-factor analysis of variance (ANOVA) was investigated. Based on the results of the MSCR test at both stress levels, modification of base bitumen by SBR, PPA and WMA additives causes an enhance in permanent deformation performance of original bitumen. LAS test results indicated that, utilization of SBR and WMA additives improves the fatigue life of bitumen. Also, by addition of PPA, the fatigue life of SBR modified binders increases. whereas, the fatigue lives are higher than original binders ones. Based on results, utilization of SBR and PPA enhances the Mr, rutting properties, ITS, FE, and fatigue behavior of specimens. By increasing the PPA percentage, the rutting and fatigue behavior enhances. Whereas, it causes a decreases in Mr and ITS of modified mixtures. Among warm additives, sasobit has better effect on enhancing the performance of binders and mixtures.