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In an effort to understand how tire tread separation affects vehicle handling, a series of tread separation handling test programs were conducted. ...Catastrophic and sudden tire tread separation is an event that drivers of motor vehicles may encounter and, in some instances, is implicated as the cause of motor vehicle crashes and related injury or property damage. ...In each tread separation test program a sport utility vehicle was instrumented and equipped with steel belted radial tires that were modified to emulate tread separation between the inner and outer steel belts.

The tests were categorized as tread separation event tests and tread-separated tests. The tread separation event tests were designed to determine how the vehicle responds as the tread is separating from the tire carcass at speeds ranging from 58–119 km/h (36–74 mph). ...A series of open loop tests was conducted on three vehicles instrumented per SAE J266 to determine the effect of a rear tire tread separation on the vehicles’ behavior. The vehicles tested were a 1989 Ford Bronco II, a 1996 Ford Explorer, and a 1993 Ford Taurus. ...Tires were prepared in a manner that would initiate either a complete or partial separation of the tread. The vehicle was driven on a straight path with the steering wheel held fixed as the tread came off.

In this study, tests were performed with modified tires at the various front and rear positions on seventeen different vehicles to determine the effect of a full tire tread belt separation on a vehicle at highway speeds. The driver's steering and braking inputs were measured along with the vehicle responses during the event. ...The results show that the forces of a full tread belt separation generally do not force a vehicle out of a driver's control and that only small steering corrections are required to remain in the original lane of travel during the tread belt separation event. ...The results show that the forces of a full tread belt separation generally do not force a vehicle out of a driver's control and that only small steering corrections are required to remain in the original lane of travel during the tread belt separation event. Additionally, forces due to the separating tires do not result in violent hop or tramp suspension responses during the separation event.

Tread belt separation and detachment is a common failure mode of radial tires. The accident reconstructionist is frequently asked to evaluate the effect of tread belt separation and detachment relative to the occurrence of an accident. ...The accident reconstructionist is frequently asked to evaluate the effect of tread belt separation and detachment relative to the occurrence of an accident. Publications have previously been directed toward defining the effects of rapid tire deflation on vehicle drag and handling. ...However, little has been written about the singular effect of the loss of the tire tread belt relative to vehicle handling. The loss of a tread belt from a tire may be followed by rapid deflation.

Yaw tests were performed using tires that were intact and tires that had the tread removed. The tires that had the tread removed were placed at various wheel positions on the vehicle (e.g. leading side - front, leading side -rear, trailing side - rear). ...This testing simulates the loss of control phase subsequent to a tread separation. Speeds up to 117 km/h (72.9 mph) were achieved. A simple electro-mechanical device was incorporated to the dynamic testing to simulate a low-severity non-deployment event that triggered the recording of pre-crash data by the SDM. ...This paper examines the dynamic effect of high sideslip angles and changes to tire rolling radius, as a result of a tread separation, as it pertains to the accuracy of EDR reported vehicle speed.

Electronic Stability Control (ESC) has the potential of improving yaw stability and reducing the occurrence of a crash when a vehicle experiences a rear tire tread separation. Two instrumented 4-door, RWD SUV’s equipped with ESC were tested to evaluate the effectiveness of their ESC systems on maintaining yaw stability under these circumstances. ...This will likely have a positive effect on a driver’s ability to maintain control when faced with a rear tire tread separation under real world circumstances....The test vehicles were evaluated with the tread and outer steel belt removed from the right rear tire. Tests were run with the ESC engaged and then repeated with the ESC disengaged.

Vehicles were tested with delaminated tires (i.e. tires where the tread and upper steel belt were removed) placed on the front suspension as well as the rear. These tests were performed using open loop steering evaluations at highway speeds and according to the Society of Automotive Engineers procedure J266, which includes testing to measure the steering required to follow a circular path at ever increasing speeds until the limits of tire traction are exceeded. ...The SAE J266 one hundred foot circle test was performed with both good tires and with a front or rear tire that had a totally separated tread and upper belt. In the tests with good tires, the vehicles could achieve a maximum lateral acceleration in the range of 0.65 g to in excess of 0.80 g in both clockwise and counterclockwise directions. ...In constant radius testing with the missing tread tire on the rear suspension, the vehicles could achieve in the range of 0.50 to 0.75 g lateral acceleration in a turn with the separated tire on the inside or unloaded side of the vehicle.

The results of this study demonstrate that ESC systems can be overwhelmed by some steering demands when a rear tire has lost its tread. This fact does not constitute a problem with the ESC systems or the vehicles tested. It merely confirms that ESC systems will not always keep a vehicle from sliding or spinning out when a tire is disabled.

Tire tread separation events, a category of tire disablements, can be sub-categorized into two main types of separations. These include full tread separations, in which the tread around the entire circumference of the tire separates from the tire carcass, and partial tread separations, in which a portion of the tread separates and the flap remains attached to the tire for an extended period of time. ...Relatively, there have been few partial tire tread separation tests presented in the literature compared to full tread separation tests. In this study, the results of 25 full and partial tire tread separation tests, conducted with a variety of vehicles at highway speeds, are reported. ...These include full tread separations, in which the tread around the entire circumference of the tire separates from the tire carcass, and partial tread separations, in which a portion of the tread separates and the flap remains attached to the tire for an extended period of time.

The results of this study demonstrate that utilizing circumferentially cut tires is appropriate to evaluate the effects that a tread separation may have on vehicle performance. Also, the forces created in the tire tread separation tests performed did not force the vehicle out of the drivers’ control. ...In this study, tests were performed with modified tires at the right rear location on a solid rear axle sport utility vehicle to compare the vehicle inputs from both: (1) tire tread belt detachments staged by circumferentially cut tires, and (2) a tire tread detachment staged by distressing a tire in a laboratory environment. ...The data shows that the tire tread belt detachments prepared by circumferentially cut tires and distressed tires have similar inputs to the vehicle.

The tests document the longitudinal and lateral forces generated while the tread is detaching during different types of tread separation events. The results demonstrate that magnitude and duration of forces depend upon the nature of the tread separation event. ...Additional documentation includes high speed and real time video of the tread separation events to provide insights into tread detachment modes and mechanisms of measured force response. ...A series of tests were conducted utilizing a tire test machine built to measure forces during a tire tread separation event. Tires were prepared by cutting between the two steel belts inward from the shoulder area.

Recently, papers have been published purporting to study the effect of rear axle tramp during tread separation events, and its effect on vehicle handling [1, 2]. Based on analysis and physical testing, one paper [1] has put forth a mathematical model which the authors claim allows vehicle designers to select shock damping values during the development process of a vehicle in order to assure that a vehicle will not experience axle tramp during tread separations. ...Based on analysis and physical testing, one paper [1] has put forth a mathematical model which the authors claim allows vehicle designers to select shock damping values during the development process of a vehicle in order to assure that a vehicle will not experience axle tramp during tread separations. In the course of their work, “lumpy” tires (tires with rubber blocks adhered to the tire's tread) were employed to excite the axle tramp resonance, even though this method has been shown not to duplicate the physical mechanisms behind an actual tread belt separation. ...In the course of their work, “lumpy” tires (tires with rubber blocks adhered to the tire's tread) were employed to excite the axle tramp resonance, even though this method has been shown not to duplicate the physical mechanisms behind an actual tread belt separation. This paper evaluates the theories postulated in [1] by first analyzing the equations behind the mathematical model presented.

Some have used lumpy tires in attempt to model the force and displacement inputs created by a tire tread belt separation. Four configurations were evaluated for the lumpy tires: 1-Lump, 2-Lump (2 lengths), and 3-Lump. ...The results show that the stepped diameter tires do not create inputs to the vehicle and responses from the vehicle similar to a tread belt detachment. In addition, the use of lumpy tires as surrogates for tread belt detachments to study the resulting vehicle responses was shown to be not valid. ...The forces created in the tire tread separation tests performed did not force the vehicle out of the drivers' control.

It was shown that applying a common numerical setup, with velocity boundary condition prescribed on the tread, significant errors were introduced in the simulation. The contact patch separation was exaggerated and the flow field from wind tunnel measurements could not be reproduced. ...Previously, the authors studied a treaded, deformable, isolated full-scale tire rotating in contact with the ground in the wind tunnel and using the Lattice-Boltzmann solver Exa PowerFLOW. ...Thus, the effect of tread rotation can be investigated separately from the effect of a deformed contact patch. In the simulation this is achieved by including the whole wheel in a sliding mesh region.

This specification covers one type of cushion tread (semi-pneumatic) wheels for use on mobile ground support equipment.

To determine the ability of a fuel/water separator to separate emulsified or finely dispersed water from fuels. This test method is applicable for biodiesel fuel.

To determine the undissolved water removal performance of a fuel/water separator under controlled laboratory conditions, using water droplets. This test method is applicable for diesel and biodiesel fuel.

This SAE Recommended Practice sets forth a method for measuring pressure-induced separation in automotive sealers and determining the likelihood of equipment failure due to this separation, also known as "caking." ...This SAE Recommended Practice sets forth a method for measuring pressure-induced separation in automotive sealers and determining the likelihood of equipment failure due to this separation, also known as "caking."

This water separation technical report has been established to cover heavy-duty engine intake filter systems. ...It may also be applicable to some automotive and industrial air inlet systems where water separation is an issue.