Tire Configurations Research Articles

Fatigue life prediction and structural optimization design of the bionic petal non-pneumatic tire with spokes

Fatigue durability of the non-pneumatic tire (NPT) has a decisive influence on vehicle safety and transport economy. This paper aims at the research on the fatigue life prediction method suitable for the flexible spokes of the NPT, and explores the influence of structural parameters on fatigue performance. By simultaneously taking consideration of fatigue performance, bearing capacity, and weight of the NPT, the optimal model parameters are obtained by the proposed structural optimization method. Firstly, based on the Thomas crack model, the fatigue life of the bionic petal non-pneumatic (BP-NPT) is predicted. Then, the influential mechanism of key structural parameters including the curvature, array period, and spoke thickness on tire fatigue durability is investigated by numerical simulation methods. Finally, an optimization method based on the Kriging model and modified NSGA-II is proposed to optimize the structure characteristics of the BP-NPT for better fatigue life and bearing capacity while ensuring lightweight. The results show that the predicted fatigue failure mileage of the BP-NPT is 2.54 × 104 km. By properly increasing the curvature and thickness of the spoke, the maximum strain energy density of the BP-NPT will be reduced, thus improving its fatigue durability. The performance of the optimized structure is significantly improved by the proposed optimization method. The total mass is reduced by 7.44%. The fatigue life and bearing capacity are improved by 9.75% and 4.16%, respectively. It is indicated that a more durable and safer tire configuration is provided for tire safety applications.

Incorporation of Pavement Dynamic Loading in Mechanistic–Empirical Design Frameworks

A framework for incorporating dynamic loading in pavement design is introduced. The framework is composed of five main steps. Firstly, input parameters, such as traffic characteristics, material properties, and the pavement configuration, are determined. Both primary and secondary data were obtained from the literature in this step. Secondly, a database of critical pavement responses, used by AASHTOWare software’s transfer functions to calculate pavement damage, was built using advanced pavement finite element models after the loading input was defined. The database includes various pavement configurations, axle configurations (single and tandem), pavement material properties, temperatures, loading conditions, and tire types (single steering, dual, and wide-base). AASHTOWare’s transfer function predicts pavement damage from pavement responses and is used to calculate the international roughness index (IRI) in the third and fourth steps, respectively. Finally, the load spectrum is adjusted to incorporate roughness-induced dynamic loading once the IRI exceeds 95 in./mi. A simple analytical dynamic-loading model was developed, based on mechanistic truck–trailer results. The model is a function of the tire configuration, speed, and IRI. Multiple case studies were performed, considering various pavement configurations, material properties, average annual daily traffic values, and dynamic-loading percentiles. Results showed that dynamic loading had the most significant impact on fatigue life, followed by rutting potential. The AASHTOWare’s transfer functions were found to be insensitive to an increase in loading when considering thick-pavement structures. The outcome of this effort was validated using the measured and predicted IRI from the Specific Pavement Study sections, which are part of the Long-Term Pavement Performance program.

Influences of bus traffic loading on asphalt concrete rutting

ABSTRACT Permanent deformation is the primary failure mode for the asphalt concrete (AC) pavement in urban environment. It is mainly caused by a combination of heavy traffic load, low vehicle speed and channelised traffic. A rut prediction model would therefore be a valuable tool for planning maintenance scheduling and selecting an appropriate asphalt material. This study uses the PEDRO (Permanent deformation in asphalt concrete layers for roads) model to evaluate the rutting performance of flexible pavements in dedicated bus lanes and intersections in urban areas. For this purpose, three road sections along a bus lane in Malmö, Sweden, were selected. To achieve this, AC cores from the road sections were tested using a Shear Box Tester to characterise the asphalt mixtures. Traffic data such as axle load, tyre configuration, speed, and lateral wander distribution of vehicles, and climate data were measured for the selected sections. Field measurements were carried out to assess the structural conditions of the pavements and to measure transverse profiles. This study introduced a procedure for the evaluation and local calibration of the PEDRO rutting model. The results revealed that the prediction of the transverse profiles are generally in good agreement with the rut measurements.

Tyre Configuration and Axle Load of Front-Wheel Assist and Four-Wheel Drive Tractors Effects on Soil Compaction and Rolling Resistance under No-Tillage

Selecting the appropriate tyre configuration and settings for heavy farm vehicles is important to ensure that soil compaction and power loss in rolling resistance are minimised and traction is optimised. This study investigated the effect of front-wheel assist (FWA, ≈75 kN) and four-wheel drive (4 WD, ≈100 kN) tractors fitted with different tyre configurations (single, dual), tyre sizes and inflation pressures on soil strength (a proxy for soil compaction), and rolling resistance. Single-pass tests were performed on a Typic Argiudoll (≈23% clay, bulk density: 1305 kg m−3) managed under permanent no-tillage. Results showed that average power losses in rolling resistance were 7.5 kN and 5 kN for the 4 WD and FWA tractors, respectively. The average rut depth increased by approximately 1.4 times after a pass of the 4 WD compared with the FWA tractor. The soil cone index (0–600 mm depth) increased from 2023 kPa (before traffic) to 2188 and 2435 kPa after single passes of the FWA and 4WD tractors, respectively (p < 0.05). At the centreline of the tyre rut, dual tyres reduced the soil cone index a little compared with single tyres, but they significantly increased the volume of soil over which soil strength, and therefore soil compaction, was increased. For both tractors (regardless of tyre configuration or settings), soil strength increased to the full measured depth (600 mm), but relative changes before vs. after traffic became progressively smaller with increased soil depth. The power loss in rolling resistance was consistently greater with the heavier tractor, and rut depth was directly related to tyre inflation pressure.

Fatigue damage analysis of pavements under autonomous truck tire passes

Abstract Two different tire configurations consisting of a dual tire and a super single wide tire having different range and distribution of contact pressures have been analyzed. Along with the effect of speed on development of pavement damage at speeds of 5, 50 and 80 km h−1 under zero and uniform wander modes. Results show that at super slow speeds of 5 km h−1, at dual wheel moving at zero wander mode, decrease in fatigue life of the pavement is 3.5 years, which is 1.45 times more than the dual wheel moving at uniform wander and 3.4 times more than wide tire moving at uniform wander mode. The difference between fatigue damage at different lateral wander modes is prominent at speeds greater than 50 km h−1. A wide tire performs better than the dual wheel under zero wander configurations.

Numerical simulations of complex water spray flows around aircraft landing tire

When an aircraft passes through the contaminated runway, the water spray generated by the landing gear may enter the inlet of the engine and affect the operation of the engine. In this paper, the formation of tire spray and the complete splashing trajectory under a complex flow field are calculated by numerical simulations. Firstly, the initial patterns of tire water spray are simulated by the Smoothed Particle Hydrodynamics (SPH)-Finite Element (FE) coupling method in LS-DYNA software package, and the engine flow field is simulated in CFX software package. Secondly, the water spray particles information and engine flow field information are imported into a program to calculate the splashing trajectory under the influence of the complex flow field. In the process, the particles inhaled by the engine are counted, so the engine water inflow can be obtained under different working conditions and tire configurations, which can verify the suppression effect of the tire chine on the engine water inflow. Lastly, the complete splashing trajectory of the complex flow field simulated by the program is consistent with the result of the aircraft splash test, which proves the feasibility of the numerical simulation method for the complete splashing trajectory simulation.

Simulating the Impact of Vehicle Speed on the Life of Bituminous Pavement

Due to the visco-elastic nature, the performance of flexible pavements depends on temperature and loading conditions. This study investigates the influence of different speeds of vehicle and binder type on stiffness modulus and the corresponding pavement life. The filed data was collected from the pavement section at Bukit Mertajam, Penang, Malaysia. The data were used to determine the stiffness of binder and corresponding stiffness of wearing and binder courses at different vehicle speeds (30, 50, 70 and 80 km/h) using analytical equations. The data of layer properties (stiffness and poison’s ratio) and axle loading (wheel load, tyre configuration) were incorporated in BISAR software to determine the horizontal tensile strain at bottom of binder layer and vertical compressive strain at top of subgrade. The strains were then used to predict pavement life passed on fatigue and rutting failure criteria. It was concluded that increasing the speed of the vehicle (from 30 km/h to 80 km/h) causes about 24% increase in stiffness modulus of wearing course. Similarly, asphalt mixture with Pen 80/100 grade bitumen has a lower stiffness modulus than Pen 60/70 grade bitumen. Furthermore, reducing vehicle speed (i.e., increasing loading time) causes a reduction in fatigue and rutting life of the pavement. Therefore, it is required to consider the speed of the vehicle while designing flexible pavement in addition to other mixed design considerations.

Spectroscopic ellipsometry methods for brevetoxin detection

The spectroscopic ellipsometry (SE), and attenuated internal reflection spectroscopic ellipsometry (TIRE) are promising methods in label-free biosensing applications. An ellipsometer running under surface plasmon resonance (SPR) conditions has unique advantages over other SPR-based methods in terms of sensitivity and real-time/label-free measurement capability. In this study, both SE and TIRE-based brevetoxin B (BTX) sensors were developed using two anti-BTX aptamers reported before. A new aptamer sequence was also derived from these two antiBTX aptamers using predictive modeling tools and an exclusion method. All three antiBTX aptamers' analytical performances were quite competitive in terms of both detecting range and detection limits. However, the selectivity of the previously reported aptamers against analogs of BTX was poor at low detection ranges, especially for okadaic acid. Furthermore, the selectivity of the derived aptamer was lower than its predecessors. The sensors were capable of detecting BTX in the range of 0.05 nM–1600 nM in the TIRE and 0.5 nM–2000 nM in the SE configuration. The detection limits of the sensors were 1.48 nM (1.32 ng/mL) and 0.80 nM (0.72 ng/mL) for SE and TIRE configurations, respectively. Both configurations have been used successfully to detect BTX standards spiked into real fish and shrimp samples.

Energy Absorption in Actual Tractor Rollovers with Different Tire Configurations.

In order to better understand the complexities of modern tractor rollover, this paper investigates the energy absorbed by a Roll-Over Protective Structure (ROPS) cab during controlled lateral rollover testing carried out on a modern narrow-track tractor with a silent-block suspended ROPS cab. To investigate how different tractor set-ups may influence ROPS and energy partitioning, tests were conducted with two different wheel configurations, wide (equivalent to normal ‘open field’ operation) and narrow (equivalent to ‘orchard/vineyard’ operation), and refer to both the width of the tires and the corresponding track. Dynamic load cells and displacement transducers located at the ROPS-ground impact points provided a direct measurement of the energy absorbed by the ROPS cab frame. A trilateration method was developed and mounted onboard to measure load cell trajectory with respect to the cab floor in real-time. The associated video record of each rollover event provided further information and opportunity to explain the acquired data. The narrow tire configuration consistently subjected the ROPS cab frame to more energy than the wide tire arrangement. To better evaluate the influence of the ROPS cab silent-blocks in lateral rollover, static and dynamic tests were performed. The results confirm that tires influence the energy partition significantly and that further understanding of silent-blocks’ dynamic performance is warranted.

Total internal reflection ellipsometry for kinetics-based assessment of bovine serum albumin immobilization on ZnO nanowires

The properties of the ZnO-NWs were investigated by utilizing spectroscopic ellipsometry under TIRE configuration during real-time measurement of covalent BSA immobilization.

Numerical analysis applied to the study of soil stress and compaction due to mechanised sugarcane harvest

Crop harvesting has been pointed as the main source of soil compaction in sugarcane fields because of the high stresses induced by the machinery; however, little is known about the magnitude of the stress transmitted to the soil by these machines in the compaction process. The aim of this study was to use numerical simulations to analyse the impact of vehicles used in mechanised sugarcane harvesting on soil stress and soil compaction response. For that, numerical simulations were performed for a set of machines and tyre configurations used to harvest sugarcane: tractor, truck and trailer. The model was formulated as a 2D plane strain problem, meshed for a soil domain 9.0 m in width and 4.0 m in depth, while using the Modified Cam Clay model as the constitutive relationship. Up to 1 m depth, the domain was layered every 0.20 m using measured soil mechanical properties. Effective vertical stress, precompression stress and soil total porosity were analysed in response to the applied stress by the harvest machines. The truck and the trailer applied stresses to the soil surface that reached 800 kPa, while the stresses applied by the tractor did not exceed 300 kPa. Numerical simulations showed that the truck and the trailer can transmit stresses higher than precompression stress that exceeds 1.00 m depth, causing a reduction in the soil total porosity and hence subsoil compaction. These stresses can extend to the planting row by stress bulbs overlapping at around 0.60 m, and could cause soil damage in case of greater stress than precompresion stress. Finally, the simulations revealed variability in soil compaction as dependent on the magnitude of the transmitted stress, as well as due to heterogeneity of mechanical properties along the soil profile. The simulations indicate the relevance of detailing the compressive properties of arable soils rather than considering the soil profile as homogeneous.

Justification of the Number and Type of Tire Size for a Dump Truck with a Lifting Capacity from 90 to 130 Tons

The article substantiates the quantity and type of tire size for a dump truck with a carrying capacity from 90 to 130 tons. Types of tire sizes for dump trucks are given, as well as an analysis of applicable tires for dump trucks. An example of tire configuration for a dump truck is described, as well as the differences between projects and dump trucks with the traditional arrangement of large tires. The working productivity of large tires was cal- culated using the TKH “tons per kilometer per hour” technique. The general tasks that need to be addressed when designing a dump truck are highlighted. The conclusion is made on the relevance of the development of scientifically based approaches when designing dump trucks. The above data indicate that when surface mining, it is possible to solve the economic problem of reduc- ing the operating costs of transporting minerals by applying the proposed arrangement and number of large tires when designing new dump trucks, including robotic and unmanned ones.

Effect of Axle and Tire Configurations on Flexible Pavement Response

The aim of this research is to analyse flexible pavement mechanistic response to axle configurations and tire variations with the help of KENPAVE program based on field survey conducted in Cipularang Highway Km. 97. Each tire load was obtained from the axle load divided by the number of tires. Vertical compressive strain was used to analyze rutting damage while horizontal tensile strain was used to analyze fatigue damage. The results showed that on single axle single tire, the biggest strain value is at the center of the tire. Single axle dual tires obtains biggest strain at the tire radius. Tandem and tridem axle dual tires obtain biggest strain values at ½ distance between tires. Vertical and horizontal strain value on the vehicles are not only influenced by vehicle loading but also axle configuration. Number of allowable repetitions is inversely proportional to vertical and horizontal strain value, which means that the bigger vertical strain value is, the number of vehicle reps that can cross the road without causing rutting damage will be smaller.

Agricultural tractor performance with different wheel and tire configurations

This study evaluates the performance of an agricultural tractor with a maximum power of 92.4 kW (125.6 hp), equipped with different wheel and tire configurations. The experiment was carried out in the field, with a random­ized block design in a trifactorial scheme, with two wheel and tire configurations (double wheel and diagonal tire; single wheel and radial tire), three mass-power ratios (61, 67, and 74 kg kW -1 ), and three levels of partial loads imposed on the drawbar (24, 27, and 36 kN), on firm soil covered with vegetation. The data were recorded by means of electronic instrumentation installed in the tractor. The results indicate that the double wheel and diago­nal tire configuration showed better performance regarding traction force, traction power, and traction efficiency, as well as lower specific fuel consumption. In turn, the simple wheel and radial tire configuration showed the low­est values of driving wheel slipping. The best traction performance was obtained with the mass-power ratio of 67 kg kW -1 for the double wheel and diagonal tire configuration, and 61 kg kW -1 for the single wheel and radial tire configuration.

Structural and environmental impact of new-generation wide-base tires in New Brunswick, Canada

The loading and environmental impacts of new-generation wide-base tires (NG-WBT) and dual tire assemblies (DTA) on typical asphalt concrete (AC) pavement sections of New Brunswick, Canada were evaluated using finite element method (FEM) analysis and life-cycle assessment. The impact of steering wheel was not considered in this study. The analysis considered realistic material models and loading conditions (i.e. AC viscoelastic characteristics and measured three-dimensional nonuniform tire–pavement contact loads). Predicted critical pavement responses were used in transfer functions to determine potential pavement damage. The NG-WBT loading resulted in greater critical pavement responses compared to that of DTA, especially near the surface (e.g. Vertical shear strains in AC). On the other hand, subgrade response (i.e. maximum vertical strains) to loading was similar for both tire configurations. NG-WBT market penetrations and pavement service life are inversely related. For example, an NG-WBT market penetration of 20% resulted in an 8% greater pavement damage. However, the higher the NG-WBT market penetration is, the greater fuel savings and, therefore, the fewer the emissions and greenhouse gases. Hence, both structural and environmental impacts must be considered.

Proposing an Updated AM2 Mat Performance Criteria Model

The AM2 mat system is historically one of the most deployed portable airfield mats in the military. The current AM2 airfield mat performance criteria for determining the number of coverages an AM2 mat can sustain before failure is an empirically correlated model and cannot accurately predict the number of coverages to failure beyond lower subgrade (California bearing ration) CBR or for modern aircraft with multiple tire configurations. This paper presents a stress-based model that predicts the number of coverages to failure using the maximum deviator stress as the performance index normalized by the subgrade CBR. The proposed model addresses different aircraft tire configurations on the AM2 mat over subgrade CBR values extending up to 100. Some improvements made to current criteria include (1) the addition of more test data at higher subgrade CBR values, (2) a fitted curve that more reasonably addresses early permanent deformation failures due to loads at low CBR, (3) a reasonable “cap” to the service life of an AM2 mat due to failure from mat breakage at high CBR, (4) a consolidation of previous “families of curves” for different equivalent single wheel loads and CBR values into one single regression curve, and (5) a performance index calculated using layered elastic analysis ( WinJULEA). This paper presents a comparison of the proposed model with the current performance criteria against the full-scale test data. Results show that the proposed model has a high correlation to the test data ( R2 = 0.952) and performs very well with respect to the current performance criteria.

Computational investigation of hydroplaning risk of wide-base truck tyres on roadway

The risk of hydroplaning is one of the major safety concerns at rainy weather condition for both travel public and highway agencies. Most previous studies have focused on analysis of hydroplaning for passenger car tyres while giving limited importance to truck tyres. This study aimed to investigate hydroplaning risk of truck tyres and compare hydroplaning speeds of different tyre configurations using three-dimensional (3-D) fluid–structure interaction models. The validation of hydroplaning simulation model was performed against the field test results from existing literature. The results show that the wide-base 445 tyre provides better safety performance than the conventional wide-base 425 tyre and dual tyre assembly with 11R22.5 tyre under wet weather condition. The hydroplaning potential increases with the increase in water film thickness on pavement surface. On the other hand, the high wheel load or high tyre inflation pressure positively increases hydroplaning speed. In addition, the analysis results demonstrate that the truck tyre under sliding condition has the higher hydroplaning risks than the tyre under free rolling condition. These factors should be considered together when developing safety improvement countermeasures for driving safety.

Modelling of optimal tyre selection for a certain truck and transport application

The main aim of the research leading to this paper is to select - for a truck and its transport application - a configuration of the tyres such that the energy losses caused by these are minimised. We show that neither the rolling resistance coefficient (RRC) classes provided by tyre suppliers nor any other nominal values of RRC evaluated for specific operating conditions are sufficient to do the tyre selection. Therefore, a surrogate model of the RRC is developed. A tyre model based on the RRC model is introduced in this paper. The modularity of the tyre model is demonstrated by coupling it with two different vehicle models and an operating environment model. The usage of the joint vehicle, tyres, and operating environment model is demonstrated by solving a few illustrative instances of the tyre selection problem. The potential savings with respect to energy losses when the selected tyre configurations are used are presented.

Modelling of optimal tyre selection for a certain truck and transport application

The main aim of the research leading to this paper is to select---for a truck and its transport application---a configuration of the tyres such that the energy losses caused by these are minimized. We show that neither the rolling resistance coefficient (RRC) classes provided by tyre suppliers nor any other nominal values of RRC evaluated for specific operating conditions are sufficient to do the tyres selection. Therefore, a surrogate model of the RRC is developed. A tyre model based on the RRC model is introduced in this paper. The modularity of the tyre model is demonstrated by coupling it with two different vehicle models and an~operating environment model. The usage of the joint vehicle, tyres, and operating environment model is demonstrated by solving a few illustrative instances of the tyres selection problem. The potential savings wrt. energy losses when the selected tyre configurations are used are presented.

Efficient surrogate method for predicting pavement response to various tire configurations

A computationally efficient surrogate model was developed based on artificial neural networks (ANN) to investigate the effect of the new generation of wide-base tires on pavement responses. Non-uniform tire contact stress measurements were obtained using a stress-in-motion instrument. The measured 3-D contact stresses were applied on two extreme 3-D flexible pavement finite element models representing low-volume (thin) and high-volume (thick) roads. Eleven critical pavement responses were modeled at two different material properties input levels--detailed and simplified--depending on data availability. The results rendered by the ANN surrogate models were highly accurate with average prediction error less than 5 % and R-square values higher than 0.95. In addition, two sensitivity analyses were performed to investigate the variables effect on pavement responses. It was found that the type of tire (wide-base vs. dual tire assembly) is more influential than the inflation pressure on pavement responses. However, the tire inflation pressure seemed to have a significant effect on near-surface responses. The developed models were incorporated into a tool to assist designers and engineers in investigating the effect of the pavement responses of wide-base versus dual tire assembly under typical loading conditions and pavement structures.