Truck Axle Research Articles

The single container loading problem with axle weight constraints

Abstract This paper considers a single container loading problem with practical constraints that address the U.S. legal requirements stipulated in the California Vehicle Code (CVC) related to truck axle weight. The problem is computationally intractable for practical problem cases. We propose an integrated heuristic solution approach that combines a GRASP wall-building algorithm with linear integer programming models. Experiments are conducted using data generated from real cases showing the effectiveness of our approach. This work has been developed into a software component to facilitate decision makers in the industry.

Truck Parking Cheating Detection System of the Truck Scale Using the Voltage Waveform Analysis

Truck scale is an important weighing instrument. The truck parking cheating method is one of the truck scales cheating method and can lead to large economic losses to the enterprise. A new truck parking cheating detection method based on the voltage waveform analysis is brought out in this paper. According to the output voltage signal waveform of the weighing transducer, if the turning point number of the output voltage is different with the truck axles, the truck parking cheating method exists. Based on the principle, the truck parking cheating detection system is designed. The instrument is using 8031 as the MCU and can be transmitted the voltage signal to the control computer. Experimental data show that the detection system can on-time detects the truck parking cheating method.

The Experimental Research of Axlehousing Hydroforming Processing

The axle housing manufactured by hydroforming can meet the requirement of light weight in automotive making. The products are of reasonable thickness distribution, high strength and rigidity. The application time of hydroforming axle housing in automotive manufacturing is not so long, its theory and process research is still not enough, accumulation of its experiences of test data and deformation regulation is rare, all this lead to difficulty in manufacturing design. Aiming at above problems, this thesis takes 1:2 scale samples of a 0.75t truck axle housing to hydroforming test and research, so as to search the regulation of axle housing hydroforming. By the use of different loading path in the two step of the processing, reasonable loading paths to the axle housing hydroforming are found. By the study of the broken tube, hydrorming limit diagram is drawn.

Evaluation of fatigue and rut damage prediction methods for asphalt concrete pavements subjected to multiple axle loads

The new Mechanistic–Empirical Pavement Design Guide (MEPDG) developed under NCHRP 1-37A does away with the American Association of State Highway and Transportation Officials-derived equivalent single axle load concept and calculates damage caused by various axle configurations directly. However, the calculation of pavement damage caused by multiple axles (tandem, tridem, etc.) is significantly affected by the summation method used to describe the response of the pavement due to the passage of a given axle type or truck configuration. In this paper, the results from different methods of accounting for the passage of a given axle group are compared using laboratory fatigue and rut data from repeated cyclic load tests. The evaluation criterion for these different summation methods was the degree of agreement with the measured laboratory performance. The results show that for fatigue damage, dissipated energy and strain area methods have an excellent agreement with the laboratory values, whereas peak and peak mid-way methods have poor agreement. This implies that it is important to consider the entire strain pulse when calculating fatigue damage under multiple axles. For rutting damage, the peak strain method has the best agreement with the laboratory values, whereas dissipated energy and peak mid-way methods underestimate the rutting damage. Finally, the MEPDG procedure for calculating the strain under multiple axles considerably underestimates the damage for both fatigue and rutting. However, model calibration in the MEPDG does improve the prediction of the damage due to multiple axles for fatigue and to a lesser extent for rutting.

Drive axle housing failure analysis of a mining dump truck based on the load spectrum

One of the key components in a mining dump truck is the drive axle housing. Failure of this component during normal use is unacceptable. Recently, early fatigue fracture became a problem during the normal working process of these machines. However, it is difficult to calculate exactly the fatigue failure life of the drive axle housing based on bench testing or pure computer simulation due to the differences between practical road conditions (such as slope and roughness) and simplified boundary conditions. To increase the reliability of analysis results a new analysis method based on dynamic strain measurement from practical mine road surface conditions combined with finite element analysis is proposed in this paper. The dynamic strain and stress on the drive axle housing is obtained by strain measurements while the truck travels over normal mine road surface conditions. The dynamic stress was analyzed using the rain-flow counting method, which can determine the amplitudes and mean values of counted cycles. The influence of the stress mean value was taken into consideration with the Morrow’s model. According to the assumption of a linear Palmgren–Miner hypothesis of damage accumulation and using typical fatigue characteristics of the material, the fatigue failure life was calculated. Analysis of the measurements showed that the dynamic stress experienced by the axle housing was far greater than expected. In order to find the factors affecting the dynamic stress of the drive axle housing, the slope of the road surface, any uneven loading and eccentricities were analyzed using the finite element method. This paper shows that the new analysis methods described are valuable tools for analyzing the reasons behind the failure of these truck axle housings.

Axle Load Distribution for Mechanistic–Empirical Pavement Design in North Carolina

A multidimensional clustering approach to generate regional average truck axle load distribution factors (ALDFs) for North Carolina is presented. The results support the Mechanistic–Empirical Pavement Design Guide (MEPDG). Weigh-in-motion data collected on North Carolina roadways are used in the analysis. A multidimensional clustering analysis based on ALDF data develops representative clusters for different highway functional classifications. Findings show that ALDF clusters have distinct characteristics for primary roads, secondary roads, collectors, and local roads. An easy-to-use decision tree based on available traffic parameters and local knowledge helps the pavement designer select the proper ALDF input. Specific contributions include a multidimensional clustering analysis that is guided by MEPDG damage-based analysis, well-defined ALDF clusters that represent specific traffic patterns in North Carolina, and a decision tree characterized by its simplicity to help pavement designers select ALDF inputs.

C108 復元機構を有するジャイロダンパによる一軸台車車両の蛇行動安定化(車両システム)

C108 復元機構を有するジャイロダンパによる一軸台車車両の蛇行動安定化(車両システム)

Creation of Truck Axle Load Spectra Using Weigh-in-Motion Data

To assure a smooth transition from the existing pavement design methods to the new mechanistic-empirical design method in the Indiana Department of Transportation, a study was conducted to create truck traffic inputs and axle load spectra of major interstate and state-owned highways in Indiana. The existing pavement design method is based on the equivalent single-axle loads (ESAL), which converts wheel loads of various magnitudes and repetitions to an equivalent number of "standard" or "equivalent" axle loads. The new design method uses axle load spectra as the measure of vehicle loads on pavements. These spectra represent the percentage of the total axle applications within each load interval for single, tandem, tridem, and quad axles. In this study, the truck traffic and axle load spectra were developed based on the historical traffic data collected at 47 sites with weigh-in-motion technology. The truck traffic information includes hourly, daily, and monthly distributions of various types of vehicles and corresponding adjustment factors, the distributions of the number of axles of each type of truck, the weights of the axles, the spaces between the axles, the proportions of vehicles on roadway lanes, and the proportions of vehicles in driving directions. This paper presents the truck traffic and axle load spectra generated from the weigh-in-motion sites as required by the new pavement design method.

Simrit launches energy-saving hub seal

Simrit is introducing its MileMaker seals worldwide for both original equipment and aftermarket, heavy-duty truck and trailer wheel and axle applications.

Process to Estimate Permit Costs for Movement of Heavy Trucks on Flexible Pavements

A process based on a mechanistic–empirical (ME) analysis was developed to estimate permit fees on the basis of truck-axle loading and configuration as well as the predicted pavement deterioration that they cause. The process was implemented in a software package, Integrated Pavement Damage Analyzer (IntPave). IntPave is a finite element–based program that calculates pavement responses, uses ME distress models to predict performance under any type of traffic load, is capable of comparing the level of distress caused by a heavy truck relative to a standard truck, and accordingly provides a permit fee. On the basis of a parametric study, it was found that, aside from the truck gross vehicle weight and axle configuration, pavement structure and the damage threshold to rehabilitation also heavily affect the permit fee.

Characterization and Development of Truck Axle Load Spectra for Implementation of New Pavement Design Practices in Louisiana

This study addresses the traffic data needs and requirements associated with the adoption of the Mechanistic–Empirical Pavement Design Guide in Louisiana. The objective of the study is to develop the truck axle load spectra from existing data and to identify possible improvements in data collection techniques. Data collected from portable weigh in motion (WIM) sites were screened by using data validation tests and were used to develop axle load spectra for different axle configurations (single, tandem, and tridem) of the primary vehicle class. A significant variation in vehicle class distributions was observed for the same roadway functional classification, and therefore an alternative grouping method based on the truck traffic classification (TTC) procedure was recommended. The results showed that Class 9 was the dominant vehicle class for single axle loads at most of the portable WIM sites located on Interstates and principal arterials. The majority of tandem axles in TTC groups appeared to belong to Class 9, whereas the majority of tridem axles in TTC groups appeared to belong to Class 10. For single axle load spectra, the developed spectra were very similar to the default values, except for TTC 5. For both tandem and tridem axle load spectra, the developed spectra appeared to differ significantly from the default values. It was strongly recommended that traffic data from portable WIM stations be collected for a longer monitoring period and that calibration be done more frequently. Another strong recommendation was to develop a strategic plan for installing permanent WIM sites and tap into axle load data from existing weight enforcement sites to supplement the data collected by portable WIM sites.

Clustering Analysis to Characterize Mechanistic–Empirical Pavement Design Guide Traffic Data in North Carolina

This paper presents attempts to generate regional average truck axle load distribution factors (ALFs), monthly adjustment factors (MAFs), hourly distribution factors (HDFs), and vehicle class distributions (VCDs) for North Carolina. The results support Mechanistic–Empirical Pavement Design Guide (MEPDG) procedures. Weigh-in-motion data support the analysis and generate seasonal factors. MEPDG damage-based sensitivity analysis shows that pavement performance is sensitive to North Carolina site-specific ALFs, MAFs, and VCDs. Similar results occur for national default values of ALF, MAF, and VCD. Hierarchical clustering analysis based on North Carolina ALFs and MAFs develops representative seasonal traffic patterns for different regions of the state. Findings show that seasonal truck traffic has distinct characteristics for the eastern coastal plain, the central Piedmont, and the western mountains. A simplified decision tree and a related table help the pavement designer select the proper representative patterns of ALF and MAF. To develop VCD factors, the approach uses 48–h classification counts and a seasonal factoring procedure to account for day-of-week and seasonal variations. The approach incorporates site-specific truck traffic to improve the accuracy of pavement design. On the basis of sensitivity analysis results, pavement performance is found to be insensitive to North Carolina site-specific and national default values of HDF; thus, the average statewide HDF values may be used as input to MEPDG. Specific contributions of this research are the relative insensitivity of pavement performance to HDF, the use of 48-h classification counts to estimate VCD inputs, and a decision tree and table to help pavement designers select the proper ALF and MAF inputs.

Binzhou Perpetual Pavement Test Road

ABSTRACT Expressway construction has been carried out on a large-scale in China. Vigorous economical development has caused rapid growth in traffic volume and truck axle loads creating a severe challenge for the pavement structure design. Therefore, the high-performance and low- maintenance cost of a long-life perpetual pavement structure is gaining attention. This paper discusses the first perpetual asphalt pavement test road in China including pavement design, data acquisition and response analysis. Dynamic stress and strain is measured and the change in response to axle load and speed at different pavement temperature is discussed. The response of different pavement sections is compared and a prediction model of pavement stress and strain is constructed.

Failure Analysis of Friction Weld (FRW) in Truck Axle Application

A section of a fractured spindle from an axle housing was metallurgically examined. The axle fractured at the friction weld (FRW) interface and was from a truck with only about 8,000 miles of service. SEM and metallographic examinations of the weld fracture revealed that a ferritic band existed at the weld interface. A significant amount of oxides and some micro-porosity was observed in the ferrite. The existence of this type of microstructure compromised the strength of the weld and resulted in the overload fracture of the axle. FRW is supposed to be a solid-state process; however, melting-solidification was evident in this case, as suggested by the band of oxides caused by liquid phase oxidation of the molten layer at the interface and micro-shrinkage porosity formed during solidification of the liquid film. Process conditions that resulted in high heat input and liquidizing of the weld interface before the upsetting stage of the friction welding process should be mitigated.

Modeling the Response of Paved Low-Volume Roads under Various Traffic and Seasonal Conditions

Since low-volume road (LVR) systems were first designed and built, events such as deregulation and free-trade agreements and changes in economic growth patterns and in manufacturing and farming practices have resulted in increased truck movements and have accelerated the deterioration of paved LVRs, such as the ones in North Dakota, which were not designed for such heavy-truck traffic. The traditional empirical methods—use of the soil factor and R-value designs and the use of visual inspection and ride quality—to assess pavement performance are not adequate. A mechanistic model that uses material data and is capable of predicting pavement response under different traffic loading and seasonal conditions is deemed necessary. An analytical approach to determine and compare pavement response for different truck axle loadings under normal, thaw, and hot summer seasonal conditions on paved LVRs is discussed. A three-dimensional finite element program is used to model the pavement response in the form of total permanent deformation (TPD) and to calculate axle and truck damage factors. Various axle loadings representing U.S. axle weight limits on steering axles with single tires, single axles with dual tires, tandem axles, and tridem axles are used in this study. Seasonal variations are modeled through material strength parameters. The analysis of the TPD responses provides greater insight and understanding of how paved LVRs react to different axle configurations, levels of loading, and seasonal variations. This analysis ultimately may help to improve paved LVR design and planning practices and enhance seasonal load limit criteria.

Effect of Heavy Multiple Axle Trucks on Flexible Pavement Damage Using In-Service Pavement Performance Data

Truck axle configurations and weights have changed significantly since the AASHO road study was conducted in the late 1950s and early 1960s. Emerging concerns about the effects of new axle configurations on pavement damage, which is unaccounted for in the AASHTO procedure, have prompted several researchers to investigate the impacts of different axle and truck configurations on pavement performance. However, there is still a need to strengthen the mechanistic findings using field data. In this paper, actual in-service traffic and pavement performance data for flexible pavements in the state of Michigan are considered. Monitored truck traffic data for different truck configurations are used to identify their relative damaging effects on flexible pavements in terms of cracking, rutting, and roughness. The analysis included simple, multiple, and stepwise regression. The results indicated that trucks with multiple axles (tridem or more) appear to produce more rutting damage than those with only single and tandem axles. On the other hand, trucks with single and tandem axles tend to cause more cracking. Pavement roughness results did not show enough evidence to draw a firm conclusion.

Measurement of Truck Axle Weights by Instrumenting Longitudinal Ribs of Orthotropic Bridge

The longitudinal ribs of an orthotropic box-girder bridge were instrumented to measure axle weights of trucks. The bending stress in the longitudinal rib is composed of a girder component, i.e., the flexural stress due to the rib’s function as part of the box-girder’s upper flange in carrying vehicles, and a rib component, i.e., the part of stress produced in the rib when it is viewed as a continuous beam supporting wheel loads. The instrumentation locations were set close to the middle support of the two-span continuous bridge to reduce girder component and impact effect. All possible wheel-supporting ribs inside the box girder were instrumented to cover most transverse locations of truck wheels. Deviating passes as well as central passes were carried out for each traffic lane in calibration tests to catch maximum stress response. The results of the calibration tests were used to solve the influence lines of the girder component and rib component at each strain gauge. With these influence lines, the rib component was separated from girder one in the stress waves of the 3-day live traffic measurements, and axle weights of the truck traffic were subsequently calculated.

Optimization of Pinion Roughing of Spiral Bevel and Hypoid Gear

Roughing plays a very important role in spiral bevel and hypoid gear manufacturing. The roughing machine settings and cutter blade profile are optimized in this article on the basis of three considerations: the transition between the roughing root and the finishing fillet is smoothened, which causes the gear to obtain minimum possible bending stress and maximum bending strength; the finishing stock is distributed evenly to improve the residual stress, which causes the distortion of pinion during the process of heat treatment; and the working load of finishing cutter tip is minimized, and the maximum cutter life is obtained. The complex shape method is successfully used to optimize the roughing machine settings and cutter blade profile. The advantages and benefits of the newly developed roughing process are verified in the manufacture of hypoid gears for a heavy truck axle in a Chinese vehicle company.

2607 一軸台車を用いたフランジ乗り上がりの基礎実験 : 輪重と横圧の測定(OS5-2 鉄道と航空機の安全,OS5 安全・安心・セキュリティー・防災,TRANSLOG 2006)

2607 一軸台車を用いたフランジ乗り上がりの基礎実験 : 輪重と横圧の測定(OS5-2 鉄道と航空機の安全,OS5 安全・安心・セキュリティー・防災,TRANSLOG 2006)

2207 防振性能を向上した一軸台車車両(システム同定・解析I,OS3 交通・物流システムのダイナミクスと制御,一般講演)

2207 防振性能を向上した一軸台車車両(システム同定・解析I,OS3 交通・物流システムのダイナミクスと制御,一般講演)