Dual Wheel Research Articles

Study of the Influence of the Variability of Traffic-Related Parameters on the Service Life of Flexible Pavement Structures in Senegal by a Mechanistic-Empirical Approach

The results of the study showed that exceeding the axle load and axle configuration are indisputably among the most damaging factors for flexible pavement structures in Senegal, made of local materials (Diack basalt, Sindia laterite). The regulatory axle load recommended by UEMOA for users is set at 11.5 tons and 12 tons for a single and twin axle respectively. For calculation purposes, this load is set at 13 tons. However, in Senegal, this axle load is often exceeded, and given the diversity of heavy goods vehicles in traffic, single axles, whose effects, according to several authors, are more detrimental to flexible pavement structures, are increasingly observed in road traffic. Differences in fatigue cracking and rutting damage between single and dual wheels, as well as load overruns, show the need to take axle configuration and possible overloads into account when dimensioning flexible pavement structures in Senegal, and when planning their maintenance, the costs of which are excessively high, according to Senegal's Autonomous Road Maintenance Fund (FERA). Keywords: Single wheel, dual wheel, damage, fatigue cracking, rutting, traffic

Effect of water wheel configurations on portable air conditioner performance in high-humidity environments: An experimental study

Nowadays, portable air conditioners (PACs) have gained a broad international market with their advantages of easy installation and flexibility. The water wheel is generally used to solve the drainage problem of the PACs in the high-humidity environment. The reasonable configuration of the water wheel can help extend the continuous operation time and improve the performance of the PACs. This study was built upon existing PACs, exploring the impact of water wheel configurations on the performance of PACs in high-humidity environments. The research revealed that among various water wheel configurations, a dual water wheel configuration functioned better than a single one to help solve drainage problem. And the water wheel configuration that sprays water to the highest temperature area of the condenser proved the most effective for condensate removal. The optimal drainage characteristics of this particular water wheel configuration corresponded to the highest Energy Efficiency Ratio (EER) observed in the PACs, with the maximum increase of 21.11% compared to other water wheel configurations. Additionally, Due to the effect of condensate, with an increase in relative humidity, there was a simultaneous rise in the EER for all water wheel configurations in high-humidity environments.

Load transfer of small-diameter GFRP and stainless steel doweled-joints in slabs-on-ground

Large diameter steel and glass fiber-reinforced polymer (GFRP) dowel bars are commonly used in rigid concrete pavements in highways for load transfer across joints to combat the concrete deterioration due to corrosion of steel dowels. Small-diameter GFRP dowel bars can be used at the expansion joints in slabs-on-ground, walkways, industrial floors and concrete-lined channels, which are not subjected to heavy traffic loads. This study investigated the performance and behavior of small-diameter GFRP dowels. GFRP dowels with three diameters (14 mm, 16 mm, and 38 mm) and stainless steel dowels (12 mm dia.) were embedded across a 25 mm-wide joint in a test slab with overall dimensions of 1500 × 750 × 200 mm3. The variables of the study were the type of dowel material (GFRP and stainless steel), the diameter of GFRP dowels, the spacing of the dowels (200 mm and 250 mm c/c), and the type of loading (monotonic and cyclic). The slabs were loaded up to the failure of the joints under a concentrated load applied at the edge of the joint. The performance of the dowel-jointed slab specimens was investigated based on the cracking and ultimate loads, modes of failure, and load-displacement response. The ability of the small-diameter dowel bars to transfer displacements across the joint was quantified using the quantitative measures of joint effectiveness (E), load transfer efficiency (LTE), and relative deflections (Δ). Failure of the specimens with 14 mm and 16 mm diameter dowels occurred predominantly due to shear failure of the dowels before the cracking of concrete. However, for the specimens with large-diameter GFRP dowels and the stainless steel dowels, failure was associated with cracking of the concrete. A smaller spacing of the GFRP dowels and a longer embedment length gave a stiffer load-displacement response. Reducing the spacing from 250 mm to 200 mm resulted in a 4.1-fold reduction in relative deflection under the AASHTO H10 design wheel load (∼35.6 kN). Increasing the dowel length had no significant effect on the load-carrying capacity of the dowel-jointed slabs. Cyclic load tests on the specimens revealed that the joint effectiveness (E) and the load transfer efficiency (LTE) of GFRP dowels were within the AASHTO and ACPA limits up to a concentrated load higher than the AASHTO HL93 dual tandem-axle wheel load (∼55.6 kN).

Development of HIL - real vehicle dual steering wheel test platform for automotive SBW system based on variable transmission ratio control

Development of HIL - real vehicle dual steering wheel test platform for automotive SBW system based on variable transmission ratio control

The status and development strategy of coalbed methane industry in China

To achieve the goals of carbon peaking and carbon neutrality under the backgrounds of poor resource endowments, weak theoretical basis and other factors, the development of the coalbed methane industry of China faces many bottlenecks and challenges. This paper systematically analyzes the coalbed methane resources, key technologies and progress, exploration effect and production performance in China and abroad. The main problems are summarized as low exploration degree, low technical adaptability, low return on investment and small development scale. This study suggests that the coalbed methane industry in China should follow the “two-step” (short-term and long-term) development strategy. The short-term action before 2030, can be divided into two stages: (1) From the present to 2025, to achieve new breakthroughs in theory and technology, and accomplish the target of annual production of 10 billion cubic meters; (2) From 2025 to 2030, to form the technologies suitable for most geological conditions, further expand the industry scale, and achieve an annual output of 30 billion cubic meters, improving the proportion of coalbed methane in the total natural gas production. The long-term action after 2030 is to gradually realize an annual production of 100 billion cubic meters. The strategic countermeasure to achieve the above goals is to adhere to “technology+management dual wheel drive”, realize the synchronous progress of technology and management, and promote the high-quality development of the coalbed methane industry. Technically, the efforts will focus on fine and effective development of coalbed methane in the medium to shallow layers of mature fields, effective development of coalbed methane in new fields, extensive and beneficial development of deep coalbed methane, three-dimensional comingled development of coalbed methane, applying new technologies such as coalbed methane displacement by carbon dioxide, microwave heating and stimulation technology, ultrasonic stimulation, high-temperature heat injection stimulation, rock breaking by high-energy laser. In terms of management, the efforts will focus on coordinative innovation of resource, technology, talent, policy and investment, with technological innovation as the core, to realize an all-round and integrated management and promote the development of coalbed methane industry at a high level.

Can Digital Finance Improve China’s Agricultural Green Total Factor Productivity?

The improvement of agricultural green total factor productivity (AGTFP) is crucial to achieve sustainable agricultural development. By matching China’s provincial digital financial inclusion index and agricultural production data from 2011 to 2020, and on the basis of using the DEA–Malmquist productivity index to measure AGTFP, the fixed effect model and Mesomeric effect model are used to empirically test the impact and mechanism of digital financial development on China’s AGTFP. Our research found that from 2011 to 2020, China experienced consistent improvement in AGTFP, which was largely attributed to advancements in technology. Interestingly, the AGTFP in non-major grain-producing areas surpassed that in major grain producing areas. Additionally, digital finance has proven to be an effective tool in boosting China’s AGTFP, the coverage subdimension, the depth of use subdimension and the digitization subdimension all significantly promote the AGTFP. Digital finance can significantly promote the efficiency and progress of agricultural green technology, which shows that digital finance promotes AGTFP in a “dual wheel” driven manner. However, the impact of digital finance on agricultural green technology efficiency and progress is more pronounced in major grain-producing areas than in non-major areas. The impact mechanism demonstrates that digital finance has the potential to stimulate AGTFP in two key ways. First, it can improve the mismatch of agricultural production resources; second, it can promote agricultural technology innovation. Therefore, it is necessary to further promote the rapid development of digital finance, optimize the rational allocation of financial resources, and formulate tailored digital finance development strategies to promote green development of agriculture.

The Evaluation of Equivalent Axle Load Equation Based on Deflection Value before and after Overlay Flexible Pavement

Some of the factors causing early damage to Indonesia’s flexible pavement system in Indonesia were allegedly caused by several things, including the Equivalent axle load (EAL) equation incompatible with Indonesia’s situation where most heavy vehicles carry overloaded loads. One effort that can be done to avoid severe damage to the road is overlaid pavement. It is suspected that the overlay on the flexible pavement will affect the shape of the EAL equation. This paper will discuss the EAL equation before and after the flexible pavement is overlaid by measuring the pavement deflection’s value using a falling weight deflectometer (FWD). The data obtained in the form of pavement deflection value is then analyzed using the regression analysis method with the permanent deformation theory approach. From the research analysis, it is obtained that the power rank value for applying the maximum load limit regulation and the type tandem axle dual wheel (TADW) shall follow determined EAL before and after overlay to the type single axle dual wheel (SADW).

DESIGN OF THE NEW RUNWAY AT SUPADIO INTERNATIONAL AIRPORT'S RIGID PAVEMENT THICKNESS USING FAA METHOD

Supadio International Airport in Pontianak is a gateway for many domestic and international tourists. In order to boost West Kalimantan's economy and tourism, PT. Angkasa Pura II (Persero) wants to expand the Supadio International Airport by adding a second runway. This article looks at how the FAA (Federal Aviation Administration) method was used to plan the thickness of the rigid pavement on the new runway at Supadio International Airport. The expected number of people and aircraft will be calculated using the double-moving average method. The anticipated time frame is 2035, with 12.763.479 passengers and 121.782 aircraft movements annually. The Airbus A330-300 requires the most considerable thickness of the concrete slab, consisting of dual tandem wheel types and a maximum take-off weight (MTOW) of 533.519 lbs. As the original soil is in poor condition, a 52.5-cm-thick embankment is required to achieve a CBR value of 6%. The rigid pavement thickness design result for the design life of 2035 is as follows: surface course = 56,39 cm, subbase course = 15,24 cm, stabilized subgrade/base soil = 52,5 cm for critical areas, and a surface course of 50,751 cm, subbase course = 13,716 cm, and stabilized subgrade/base soil = 52,5 cm for non-critical soil.

СОЗДАНИЕ ЦИФРОВОГО ДВОЙНИКА ПРОЦЕССА СБОРКИ РАБОЧЕГО КОЛЕСА КОМПРЕССОРА

A digital dual compressor wheel assembly process has been developed to predict the angular rotations of the blade assembly rotating as it rotates. The calculated angles characterize the tension in the joints of the end flanges of the blades. At the input of a digital double sequence of data on geometry deviations with control of operations on parts. During the implementation, the random forest method was used, the study of which was carried out on a set of calculated experiments performed in the ANSYS environment using the element model of the assembled impeller. The experimental results show that the calculation error does not exceed 15 minutes of arc.

(Retracted) Research on motion control method of double rear wheel independent drive robot

The mobile robot receives control commands through wireless communication in real time, and moves flexibly with desired speed, direction, and trajectory. The motion control system directly affects the overall performance of the robot system. Here, we establish the kinematic model of the independent dual rear wheel drive mobile robot, design the linear speed control rate and angular speed control rate, design the inversion controller through the backstepping method, and carry out offline simulation and real-time control research on the dual rear wheel independent drive mobile robot system. Compared with other linearization control methods, the backstepping method does not need to linearize the system, and it directly designs the recursive controller of the system while retaining the nonlinear term in the controlled object, so the designed controller has strong robustness.

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.

Creep model to determine rut development by autonomous truck axles on pavement

Abstract Impacts of autonomous truck’s passes on pavement have been analyzed in this research. Two types of lateral positioning namely zero wander and uniform wander along with a super single wide tire and a dual tire have been analyzed with variable traffic speeds in ABQUS. The study concludes with the results in favor of usage of a super single wide tire under a uniform wander mode. The highest amount of pavement damage in terms of maximum rut depth is caused by the dual wheel assembly moving under a zero-wander mode. The magnitude of rut depth increases by a factor of two when a dual tire assembly is used instead of a wide tire assembly. At a uniform wander mode, rut depth increases by 0.2 mm for every 10 km/h decrease in traffic speed within 90 km/h to 70 km/h range.

FEM based parametric analysis for investigating effect of wheel base characteristics and axle configurations on flexural stresses in rigid pavements

The main advantages of rigid pavements are their durability and ability to hold their shapes when subject to heavy traffic and extreme weather conditions. Different vehicles have different wheel base characteristics and axle load configurations, due to which the above conditions structurally affect the performance of the rigid pavements in different ways. One of the main causes of critical defects in the rigid pavement is the development of flexural stress exceeding the critical level under different conditions. In rigid pavements the critical stresses are generated with the combination of wheel load stresses and curling stresses. In this paper, the investigation of the variation of flexural stress developed in jointed plain concrete pavements under different axle load configuration and wheelbase characteristics was done using FEM (Finite Element Method). In this paper, the modelling of the rigid pavement was carried out using KENPAVE software. In modelling, effect of both axle load and temperature difference is considered. For loading effect, axle configuration of SASW (Single Axle Single Wheel), SADW (Single Axle Dual Wheel), Tandem and Tridem axle was considered in modelling. To include the combined effect of base and subgrade an equivalent modulus of subgrade reaction was considered as per the IRC-58 code provisions. Parameters related to rigid pavement were taken according to the provisions of IRC code for modelling of base case. Parameters of pavement like thickness of pavement slab, equivalent modulus of subgrade reaction, temperature difference, modulus of elasticity and location of wheel load were changed from the base case and maximum tensile stress was calculated for each axle configurations. Based on the analysis of results for different thickness of pavement slab, equivalent modulus of subgrade reaction, temperature difference, modulus of elasticity and location of wheel load, the variation of magnitude and location of maximum tensile stress was reported for given properties of subgrade, base and axle configuration.

Study of a novel rotational speed amplified dual turbine wheel wave energy converter

In this study, a novel wave energy converter is proposed, which features a dual turbine wheel to provide an amplified rotational speed to the generator. The design novelty of the system is that the counter-rotational turbine wheels are connected to the generator stator and rotor respectively through a belt-drive transmission system for amplification of the rotational speed of the generator. This arrangement enables the power take-off system to be placed inside the buoy which is above the waterline. Furthermore, the belt-drive transmission system can effectively absorb the load fluctuations or vibrations caused by sea waves. A lumped parameter analytical model of the system has been developed where the Lagrange principle is applied to analyze the motion of the system and the computational fluid dynamics simulation is employed to determine the drag coefficients of the system. The results obtained from the lumped parameter analytical model have been verified by experimental test results. The developed lumped parameter analytical model allows accurate performance prediction without the high computational cost of the detailed simulations. The proposed research method could be applied as an effective tool to explore the science of wave energy conversion and to optimize the power absorption capacity and the efficiency of the power take-off system, which is the originality of this paper and contributes to the new knowledge in this area. For this prototype of the dual turbine wheel wave energy converter with an overall underwater volume of 0.002 m3, the maximum harvested efficiency and harvested power at the wave excitation condition of 80 mm in amplitude and 0.3 Hz in frequency are 11.57%, and 26.4mW, respectively.

Calculation of Equivalent Axle Load Factor Based on Artificial Intelligence

In most road pavements design methods, a solution is required to transform the traffic spectrum to standard axle load with using equivalent axle load factor (EALF). The EALF depends on various parameters, but in existing design methods, only the axle type (single, tandem, and tridem) and pavement structure number were considered. Also, the EALF only determined for experimental axles and axle details (i.e., axle weight, length, pressure), wheel type (single or dual wheel) plus pavement properties were overlooked which may cause inaccuracy and unusable for the new axle. This paper presented a developed model based on Artificial Neural Network (ANN) for calculation of EALFs considering axle type, axle length, contact area, pavement structure number (SN), tire pressure, speed, and final serviceability. Backpropagation architecture was selected for the model for the EALF prediction based on fatigue criteria. Finally, among all reviewed ANN configuration, a network with 7-13-1 was selected for the optimum network.

Bending and SAR analysis on UWB wearable MIMO antenna for on-arm WBAN applications

Abstract Here, a planar Ultra-Wideband (UWB) wearable Multiple Input Multiple Output (MIMO) antenna is designed for on-arm wearable Wireless Body Area Network (WBAN) applications. This antenna is designed on a 100% cotton cloth substrate. The two-port MIMO antenna has a dual spinning wheel shape like radiators with the partial ground and microstrip feedings. The two partial grounds are connected to a rectangular strip to have common ground. The complete surface area of the antenna is 40 × 70 mm2. In comparison with recently published papers in the same research area, the bending and SAR analysis are also done to estimate the performance of this wearable antenna, which is the novelty of this research work. For entire UWB bandwidth, S–parameters, gain, efficiency, and diversity parameters (Channel Capacity Loss [CCL] and Envelope Correlation Coefficient [ECC]) and far-field simulations are done for all cases such as flat, bend, on body antenna, which demonstrates the appropriateness of the presented antenna to be operated to the human arm.

Spin-type forward motion mode based on double steering wheel parking AGV

PurposeThe purpose of this paper is to propose the situation that the existing parking automated guided vehicle (AGV) has a single walking mode, a spin forward motion mode based on a dual steering wheel driven parking AGV. In this way, the AGV can complete the 180° spin of the AGV in the process of straight forward.Design/methodology/approachA spin forward kinematics model of the dual steering wheel AGV is established, and a motion controller of the dual steering wheel AGV is designed based on the principle of model predictive control to complete the path following the spin forward motion mode.FindingsComputer simulations and laboratory tests were performed on this movement mode, which showed that the operation mode was feasible. It also verified that the mode can improve the handling efficiency, and also solved the problem that the parking space beside the wall could not be set and the site utilization was improved.Research limitations/implicationsThe controller should be further improved to make the operation smoother and more accurate.Practical implicationsThis mode has the applicability to the indoor logistics AGVs. In addition, it can improve the handling efficiency and also solved the problem that the storage space for goods beside the wall could not be set and the site utilization was improved.Social implicationsThis method can solve the problem due to the increasing number of private cars and parking spaces are hard to find. It increases the number of parking spaces and improves the utilization rate of the site. In addition, it also saves people the time to find a parking space and reduces car exhaust emissions in the process. It follows the requirements of sustainable development.Originality/valueThe studies in this paper provide AGV with more ideas on the issue of improving handling efficiency and site utilization and also solves the problem of being unable to set parking spaces when parking against the wall. In addition, this model has applicability to indoor logistics AGV and plays the same role.

Designing a dual steering wheel microstructured blood components sensor in terahertz wave band

We design a photonic crystal fiber (PCF) biosensor, based on the refractive index, capable of operating in terahertz (THz) region. This structure comprises a dual steering wheel (DSW) shape of large noncircular air–hole structure in the cladding region. This PCF is designed using rectangular structured air holes in core, and they are filled with blood components as analytes. We use the full-vectorial finite-element method to optimize the structural parameters and to characterize the proposed PCF. The simulation results demonstrate a high relative sensitivity for water, cytop, plasma, white blood cells, hemoglobin, red blood cells, sylgard184, biotin–streptavidin, polyacrylamide, and bovine serum albumin. As the practical sensor setup requires connecting a single-mode fiber with that of the PCF, we compute the effective area (Aeff), V-parameter (Veff), spot size (Weff), beam divergence (θ), and dispersion (β2) of the proposed PCF over the wide THz range. We envisage that the proposed fiber may not only be useful for the measurement of various blood components but also for polarization-preserving applications in the THz region.

StormPav Green Pavement the environmentally friendly pavement

Growth of economy and population density, open space is being converted to roads or other infrastructures such as buildings or parking lots reducing green space. This paper demonstrates a new type of green pavement designed to replace flexible and rigid pavements which are water impermeable and have a short design life. This type of green pavement helps reduce runoff problems in urban areas. StormPav GP is an innovative Industrialised Building System (IBS) Green Pavement which has been shown to have structural, environmental and economic advantages. However, its susceptibility to distress has yet to be analyzed. This study addresses this gap by analyzing the mechanistic properties and evaluating distress of StormPav GP as compared to flexible and rigid pavements. WinJULEA, KenPave and Circly 6.0 were used for this analysis which also investigated the effects of different tire pressures on deflections. StormPav GP was found to have lower deflection due to a tandem axle dual wheel load on any pavement surface and provided a more uniform settlement with higher elastic modulus and shear modulus than flexible and rigid pavement.

Analysis and design of two layered flexible pavement systems: A new mechanistic approach

Analysis of two layered flexible pavements is considered as a significant aspect for design of low volume roads, which typically consist of a thick granular base course directly laid over subgrade with or without a thin asphalt-wearing course. Permanent deformation or rutting has been observed to be the major distress mode in thin surfaced or unsurfaced low volume roads. In the present study, a new formulation has been proposed to determine the surface and interface deflections for both single and standard axle dual wheel assembly for a two layered pavement system. The present formulation has been developed based on mechanistic approach and the solutions obtained from 3-dimensional finite element program, using ABAQUS taking into account the influence of rectangular tire imprint, modulus of granular base course, pavement thickness and ratio of modulus of pavement and subgrade. The effect of Poisson’s ratio of granular base and subgrade is observed to be very insignificant. For the estimation of surface and interface deflections, deflection factors have been generated in the form of non-dimensional charts as a function of ratio of modulus of pavement and subgrade, and ratio of pavement thickness and tire width.