Tread Groove Research Articles

Simulation analysis for landing process of aviation tires with ice overlay

In general, amphibious aircraft is subjected to challenges with liquid water freezing to the tires or atmospheric air-cooled icing in low-temperature environments. A finite element modeling method for aviation tires was proposed in this study in accordance with LAGRANGE mesh coupling curtain and rubber to investigate and evaluate the tires' icing adaptability of amphibious aircraft and ensure landing safety. The accuracy of the model was verified through simulation calculation, and the shape dimension achieved the maximum error of less than 1.7%. The dynamic response of the vertical ground impact for ice-free and ice-overlaid tires and that of the ground impact of tires during grounded skidding were simulated and analyzed through explicit dynamic analysis. The results of the simulation analysis suggested that the size of ice fragments showed a positive correlation with the ice thickness, and residual broken ice in the tread groove led to local stress concentration in the tread. And the tread rubber stress of the ice-overlaid aircraft tire of this type was less than the tensile strength of 27.8 MPa in the landing process, thus conforming to the required standards. Moreover, a friction-time curve was plotted to examine the impact of tires on the friction force during landings.

TireEye: Optical On-board Tire Wear Detection

Automotive tire tread depth has a major influence on a car's safety and thus has to be closely monitored. However, there is currently no on-board solution that can measure tire wear with an accuracy of less than 1 mm. TireEye is an optical device mounted inside the wheel well and facing towards the road. It records the cross-section of the longitudinal tread groove and extracts its outline by means of adaptive Canny edge detection. The tread wear indicators serve es means to calibrate the scale since they provide the minimum tread depth.

Experiment and Simulation Research on the Fatigue Wear of Aircraft Tire Tread Rubber

The road surface and the tread pattern structures directly affect the wear performance of aircraft tire, especially for lateral sliding conditions. In this paper, wear tests of tread block with different draft angles and root radiuses, different interfaces, and different slip angles were carried out, and combined with the simulation, the effects of tread groove structure and slip angle on the wear mechanism were analyzed. Results indicated that the influences of draft angle were greater than the root radius; the wear geometry of the tread block decreased when the draft angle increased in the range of 0° to 15°, but for the root radius, the wear geometry of each sample was similar to a strip shape. A considerable material loss occurred at the front edge when the slip angle increased, and the slip angle was larger in the range of 0° to 45°. Combined with the simulation and wear test, fatigue wear and abrasive wear of the slide surface are dominant factors when considering the effects of tread groove structure and slip angle, and both front edges of the tread blocks roll up repeatedly; the coefficient decreases with the increase in load when the cement concrete pavement interface is dry, but for a wet interface, the coefficient decreases softly.

Does visual representation of futsal shoes outsole tread groove design resemblance its mechanical traction, dynamic human traction performance, and perceived traction during change of direction and straight sprint tasks?

We aimed to clarify the efficacy of futsal shoe outsole tread pattern on mechanically available traction, dynamic human traction performance and athlete’s perceived traction. Thirty-nine university level athletes participated two human performance tests (multiple v-cut and 5 m/20m straight sprint) on a hardwood flooring facility using three pairs of futsal shoes that were systematically ranked based on apparent design simplicity/complexity (1 = simple, 2 = moderate and 3 = complex). Further mechanical testing was carried out to measure each shoe’s actual available traction coefficient on a dry hardwood surface [available friction coefficient (AFC)]. Among the three shoes, there were significant differences of AFCs in both horizontal and lateral components (rank 2 > rank 3 > rank 1). The shoes with higher AFC (ranks 2 and 3) had a significant impact on the multiple v-cut performance (p < 0.05) and on perceived traction (p < 0.05) when compared with the shoe with lower AFC (rank 1). No significant differences were observed across all shoe ranks for the initial (5 m) and resultant (20 m) sprint times for the straight sprint test. These findings indicated that the simplex outsole performed worst and the moderately complex outsole performed best for mechanical traction, human performance and perceived traction. Moreover, compared with the moderately complex outsole, the most complex outsole comes with several specific features did not induce any advantage of these parameters. The AFCs of three tested shoes most likely explain the differences in dynamic human traction performance and perceived traction during the test including multiple change of direction.

The Influence of Footwear Tread Groove Orientation on Slip Outcome and Slip Severity

Abstract Previous research utilizing mechanical testing has revealed that footwear tread groove orientation has a significant impact on available friction. However, the influence of tread groove orientation on slip potential in human subjects has received little attention. The purpose of this study was to determine if footwear tread groove orientation influences slip outcome and severity. Thirty-six subjects were allocated into two groups matched by sex, age, height, and weight. Subjects in each group wore a shoe with a different tread groove orientation (parallel versus perpendicular). Subjects ambulated across water-contaminated porcelain ceramic tile, and their slip outcome was recorded. Slip severity was assessed by slip distance as quantified using a motion analysis system. Results indicated that the parallel groove group experienced a greater proportion of slip events (15 of 18) compared with the perpendicular groove group (9 of 18). On average, parallel grooves also resulted in significantly greater slip distances compared with perpendicular grooves (34.6 cm versus 5.6 cm). Our findings indicate that tread groove orientation has an impact on slip outcome and slip severity.

Does apparent outsole tread groove design represent mechanical traction?

In any type of sports including futsal, one of the most important aspects is the selection of footwear. Among many aspects of a shoe, the importance of traction (the shear forces performed by athle...

Finite Element Analysis for Groove Wander Prediction of Passenger Car Tires with the Longitudinal Tread Grooves

A finite element modeling technique is employed in this paper to predict the groove wander of longitudinal tread grooved tires. In generally, groove wander is the lateral force acting on a vehicle’s wheel resulting from the combination of rain grooves. If the lateral force of tire is generated by groove wander, unexpected lateral motion of vehicle will happen and it makes drivers uncomfortable. This paper describes the effect of groove wander according to the shape condition of tire tread groove and highway groove using the finite element analysis based on a static loading or a steady-state rolling assumption. The road groove can be located anywhere relative to the longitudinal tread groove. Therefore, the lateral force of the tire is changing depending on the location of the groove road. The numerical results for groove wander prediction of the longitudinal tread grooved tires are compared with the subjective evaluation. It is found that the waveform for the tire with varying grooved road position has a peak-to-peak lateral force in order to estimate the rating of groove wander. The effect of the road groove width and the pitch length on the peak-to-peak lateral force of tire is discussed. It is found that the prediction of FEA-based groove wander model using finite element analysis will be useful for the reliability design of the tire tread pattern design.

The influence of footwear tread groove parameters on available friction

The purpose of this study was to determine how footwear tread groove parameters influence available friction (COF). Utilizing a whole shoe tester (SATRA STM 603), 3 groove parameters (width, depth and orientation) were evaluated. Groove orientation had 3 levels (parallel, oblique and perpendicular), width had 3 levels (3, 6 and 9 mm) and depth had 3 levels (2, 4 and 6 mm). In total, the COF of 27 shoes, each with a distinct groove combination, was assessed on wet porcelain tile. The 27 groove combinations produced a wide range of COF values (0.080–0.344). Groove orientation had the greatest impact on COF, explaining the greatest variance in observed COF values (ŋ2 = 0.81). The most slip resistant groove combination was an oblique orientation, with 3 mm width and 2 mm depth. The least slip resistant groove combination was a parallel orientation, with a 6 mm width and 6 mm depth.

Analysis of Impact of Tire Tread Groove Depth on Hydroplaning Risk Level

Hydroplaning ranks a maior inducement of wet-weather road accidents. By way of CFD (Computational Fluid Dynamics) approach, this paper frames a finite-element meta-models for rib tires ranging in groove depth, aiming to figure out the wheel water pressures on tires under different traveling conditions, and to find out water velocities of the different parts of the tire tread. Analysis shows that the action coverage of the high pressure induced by hydradynamic pressure is correlated with the thickness of standing water, and the grooves fail to drain as designed in case of total hydraplaning. Based on the outcomes of the experiments, this paper frames the relation formula between hydradynamic pressure and traveling velocity, standing water depth and tire tread groove depth, and thus gives recommendations on speed range in wet weather driving, and also on measures for safe driving in wet weather conditions.

Analysis of Impact of Tire Tread Groove Depth on Hydroplaning Risk Level

Hydroplaning ranks a maior inducement of wet-weather road accidents. By way of CFD (Computational Fluid Dynamics) approach, this paper frames a finite-element meta-models for rib tires ranging in groove depth, aiming to figure out the wheel water pressures on tires under different traveling conditions, and to find out water velocities of the different parts of the tire tread. Analysis shows that the action coverage of the high pressure induced by hydradynamic pressure is correlated with the thickness of standing water, and the grooves fail to drain as designed in case of total hydraplaning. Based on the outcomes of the experiments, this paper frames the relation formula between hydradynamic pressure and traveling velocity, standing water depth and tire tread groove depth, and thus gives recommendations on speed range in wet weather driving, and also on measures for safe driving in wet weather conditions.

Effectiveness of Tire-Tread Patterns in Reducing the Risk of Hydroplaning

Grooving of tire tread is necessary to provide sufficient skid resistance for wet-weather driving and to reduce the risk of hydroplaning. Many different groove patterns of tire tread are found in the market. However, their relative effectiveness in reducing hydroplaning risk is generally not known to motorists and highway engineers. The effects of changes in the groove depth of a tire tread's groove pattern also deserve further investigation. This paper presents an analytical study that aims to characterize quantitatively the influence of different tire-tread patterns and groove depths on the hydroplaning behavior of passenger cars. The analysis is performed by means of a computer simulation model with a three-dimensional finite element approach. The following six forms of tire-tread groove patterns are considered: ( a) longitudinal groove pattern, (b) transverse groove pattern, ( c) V-groove pattern with 20° V-cut, (d) V-groove pattern with 40° V-cut, ( e) combined groove pattern consisting of longitudinal grooves and edge horizontal grooves, and ( f) combined groove pattern consisting of longitudinal grooves and 20° V-cut grooves. The analysis shows that a parameter computed as the groove volume per tread area of the tire is a useful performance indicator to assess the effectiveness of various tire-tread groove patterns in reducing vehicle hydroplaning risk. The significance of V-shape grooves is discussed. For vehicular operations involving both forward and lateral movements, the analysis indicates that a combined pattern would provide a good compromise in lowering hydroplaning risk sufficiently in different modes of vehicle movements.

Noise damper and pneumatic tire with compensation tread groove

A noise damper disposed in a tire cavity formed by a pneumatic tire and wheel rim is disclosed. A noise damper designed to use with a wheel rim comprises an annular body disposed around a damper-mounting portion of the wheel rim, and the annular body is made of a spongy material having an inside diameter of from 0.9 to 1.10 times an outside diameter of the damper-mounting portion. A noise damper designed to use with a pneumatic tire comprises an annular body disposed in a tire hollow, and the annular body is made of a spongy material having an outside diameter of from 1.00 to 1.10 times the maximum inside diameter of the tire hollow.

Relationship Between Measured Friction Coefficients and Two Tread Groove Design Parameters for Footwear Pads

The shoe sole geometrical design parameters are believed to be important factors affecting the coefficient of friction (COF) between the shoe/floor interface. This study is concerned with the relationship between the measured COF and the tread groove orientation and width on the footwear pad. Friction measurements using the Brungraber Mark II slipmeter were conducted. Six tread groove width/orientations designs on the footwear pads under 27 footwear material/floor/contamination conditions were tested. The results show that tread orientation and width affect the measured COF significantly. Wider grooved footwear pads result in higher COF values and footwear pads with tread grooves perpendicular to the friction measurement direction have higher COF values. A regression model using measured COF as the dependent variable and tread groove width, groove orientation, footwear material, floor, and contamination conditions as independent variables was established. The models are significant at p<0.0001 with R 2 of 0.97, which may be used in predicting the COF at the shoe-floor interface.

Influence of Belt Cord Angle on Radial Tire under Different Rolling States

Finite element modeling techniques of a rolling radial tire are discussed in this study. The rebar model is employed to simulate complex multilayer rubber-cord composites and to directly define the cord directions varying with their positions. A 3D finite element model of a rolling radial tire has been built with MSC.MARC software according to the actual construction of a 195/60R14 radial tire. This model considers the geometric nonlinearity due to large deformation, material nonlinearities of cord-rubber composites, and the nonlinear boundary conditions from tire-rim contact and tire-road contact. Based on the nonlinear finite element model, the influence of the belt cord angle on the radial tire under different rolling states is studied numerically. The shear strain of the radial tire concentrates on the edge of the belted layer, the surface of the shoulder, and the tread groove. The strain energy density of the belt end decreases with the increase of the belt cord angle. The optimum belt cord angle of the 195/60R14 radial tire is 72.

The effect of shoe sole tread groove depth on the friction coefficient with different tread groove widths, floors and contaminants

Slipping and falling are common phenomena in both workplaces and our daily activities. The risks associated with slipping and falling are related to the materials of footwear/floor, contamination condition, and geometric design of the sole. Shoe soles of various tread design are very common. Tread pattern of the shoe affects friction especially under liquid-contaminated conditions. Verification of the effects of tread groove depth is significant in assisting designers in designing proper footwear for workers exposed to slippery floor conditions. In this study, we measured the friction coefficients using the Neolite footwear pads on the terrazzo, steel, and vinyl floors under three liquid-contaminated conditions. A Brungraber Mark II slipmeter was used. The footwear pads had tread grooves with a width of either 3 or 9 mm. The depth of the tread grooves ranged from 1 to 5 mm. The results showed that tread groove depth affected the friction coefficients significantly. Higher friction values were recorded for footwear pads with deeper tread grooves on wet and water–detergent-contaminated floors. The averaged coefficient of friction (COF) gain per tread groove depth increase in millimeter under these two surface conditions ranged from 0.018 to 0.108, depending on the tread groove width, floor, and contaminant.

Measurement of Floor Slipperiness Using Footwear Pads with Various Tread Groove Width Design

Measurement of the coefficient of friction (COF) between the shoe/sole and the floor is essential in understanding the risk of slipping accidents. COF measurements between the footwear material and floor using a slipmeter were commonly performed using flat footwear pads. Such measurements might underestimate the actual slip resistance of people's daily experiences because tread groove design on footwear is very common. This research investigates the effects of the tread groove width on the measured COF. The results indicated that tread groove width significantly (p＜0.0001) affect COF under various footwear material, floor, and contamination conditions. Wider tread grooves resulted in higher COF values with a few exceptions especially on oil contaminated floor. Stepwise regression was performed to establish a linear regression model between COF and the tread groove width under footwear material/floor/liquid-contamination conditions. A seven-independent-variable model with an adjusted R^2 of 0.74 was obtained. The lack of fit test result for the model was significant at p＜0.0001, indicating that the model adequately fit the friction measurement data.

Effects of tread groove orientation and width of the footwear pads on measured friction coefficients

The shoe sole geometrical design parameters, such as tread groove orientation and groove width, were believed to be important factors affecting the COF between the shoe/floor interface. In this study, friction measurements using a Brungraber Mark II slipmeter were conducted under three footwear materials, three floors, and three contamination conditions. Six tread groove designs (2 widths × 3 orientations) on the footwear pads were tested. The results showed that all the footwear materials, floors, and the contamination conditions affected the measured COF significantly. In addition, the tread groove orientation and width also affected the COF significantly. It was found that wider grooved footwear pads resulted in higher COF values and footwear pads with tread grooves perpendicular to the friction measurement direction had higher COF values. A linear regression model using COF as the dependent variable and tread groove width, tread groove orientation, footwear material, floor, and contaminated conditions as independent variables was established. The lack of fit test result for the model was significant at p < 0.0001, indicating that the model adequately fit the friction measurement data.

MEASUREMENT OF FLOOR SLIPPERINESS USING FOOTWEAR PADS WITH VARIOUS TREAD GROOVE WIDTH DESIGN

ABSTRACT Measurement of the coefficient of friction (COF) between the shoe/sole and the floor is essential in understanding the risk of slipping accidents. COF measurements between the footwear material and floor using a slipmeter were commonly performed using flat footwear pads. Such measurements might underestimate the actual slip resistance of people's daily experiences because tread groove design on footwear is very common. This research investigates the effects of the tread groove width on the measured COF. The results indicated that tread groove width significantly (p<0.0001) affect COF under various footwear material, floor, and contamination conditions. Wider tread grooves resulted in higher COF values with a few exceptions especially on oil contaminated floor. Stepwise regression was performed to establish a linear regression model between COF and the tread groove width under footwear material/floor/liquid-contamination conditions. A seven-independent-variable model with an adjusted R 2 of 0.74 was obtained. The lack of fit test result for the model was significant at p<0.0001, indicating that the model adequately fit the friction measurement data.

The effect of shoe soling tread groove width on the coefficient of friction with different sole materials, floors, and contaminants

Tread groove design is very common in footwear. However, coefficient of friction (COF) measurements between the footwear material and floor using a slipmeter were commonly performed using flat footwear pads. Such measurements might underestimate the actual slip resistance of the footwear pad. This research investigates the effects of the tread groove width on the measured COF using four footwear materials, three floors, and four liquid-contamination conditions using a Brungraber Mark II slipmeter. The analysis of variance results indicated that the footwear material, floor, contamination conditions, and groove width were all significant (p<0.0001) factors affecting the measured COF. The hypothesis that wider tread grooves result in higher COF values was true with some exceptions especially on oil contaminated floors. A regression model, with an R2 of 0.91, was established to describe and predict the relationship between the COF and the tread groove width under footwear material/floor/contamination conditions.

1204 実稼動解析を用いたタイヤ転動時の放射音場解析

External noise radiating from tire is one of the dominant sources of vehicle. Noise generated by a rolling tire is mainly tread block vibration, air resonance in the tread groove, and tire vibration. This paper remarks on tire vibration noise generated by rolling on the road. For this purpose smooth tire was used to exclude influences of tread pattern. Because of difficulty in measuring exciting force, an operational analysis is undertaken for investigation of rolling tire vibration behavior. A rolling tire vibration is measured using the scanning Laser Doppler Vibrometers (LDV). Sound intensity is also measured to investigate the relation between vibration and sound radiation. Rolling tire sound radiation is estimated by applying the results of the operational analysis as the modal superposition for the velocity boundary condition on the tire model. Results of prediction of sound intensity radiation showed a good agreement with experiment