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Hat-sections, single and double, made of steel are frequently encountered in automotive body structural components. These components play a significant role in terms of impact energy absorption during vehicle crashes thereby protecting occupants of vehicles from severe injury. However, with the need for higher fuel economy and for compliance to stringent emission norms, auto manufacturers are looking for means to continually reduce vehicle body weight either by employing lighter materials like aluminum and fiber-reinforced plastics, or by using higher strength steel with reduced gages, or by combinations of these approaches. Unlike steel hat-sections which have been extensively reported in published literature, the axial crushing behavior of hat-sections made of fiber-reinforced composites may not have been adequately probed.

Natural fiber-reinforced composites are currently gaining increasing attention as potential substitutes to pervasive synthetic fiber-reinforced composites, particularly glass fiber-reinforced plastics (GFRP). The advantages of the former category of composites include (a) being conducive to occupational health and safety during fabrication of parts as well as handling as compared to GFRP, (b) economy especially when compared to carbon fiber-reinforced composites (CFRC), (c) biodegradability of fibers, and (d) aesthetic appeal. Jute fibers are especially relevant in this context as jute fabric has a consistent supply base with reliable mechanical properties. Recent studies have shown that components such as tubes and plates made of jute-polyester (JP) composites can have competitive performance under impact loading when compared with similar GFRP-based structures.

The Isodamp damping material (also known as Navy Damp) used in the ribs of current crash test dummies provides human-like damping to the thorax under impact. However, the range of temperature over which it can be used is very small. A new rib design using laminates of steel, fiberglass, and commercially available viscoelastic material has been constructed. Load-deflection response and hysteresis of the laminated ribs were compared with corresponding conventional ribs fabricated from steel and Isodamp. Impact tests were conducted on laminated and conventional ribs at 18.5° C, 22.2° C and 26.6° C. Results indicate that the response of the laminated ribs is essentially the same as that of the ribs with Isodamp at 22.2° C, which is the operating temperature of the conventional ribs. The variation in the impact response of the newly developed laminated ribs in the temperature range of 18.5° C to 26.6° C was less than 10%.

There has been a keen interest in recent times on implementation of lightweight materials in vehicles to bring down the unladen weight of a vehicle for enhancing fuel efficiency. Fiber-reinforced composites comprise a class of such materials. As sustainability is also a preoccupation of current product development engineers including vehicle designers, bio-composites based on natural fibers are receiving a special attention. Keeping these motivations of lower effective density, environment friendliness and occupational safety in mind, woven jute fabric based composites have been recently studied as potential alternatives to glass fiber composites for structural applications in automobiles. In the past, mechanical characterization of jute-polyester composites were restricted to obtaining their stress-strain behaviors under quasi-static conditions.

Conventional 30 mil HPR laminated and wide-zone monolithic tempered windshields are compared on a safety performance basis from the stand-points of occupant injuries from frontal force collisions and injury or loss of control from breakage from high speed external impact of stones. All experiments were conducted with the windshields installed by conventional methods in an automobile. Occupant injury potential as measured by the Severity Index for brain damage at a 30 mph barrier impact simulation was approximately two times as high for the tempered as for the laminated windshields, although only one tempered windshield exceeded the recommended maximum value of 1,000. Severe lacerations resulted in all impacts in which the tempered glass broke. Less severe lacerations were found for the laminated windshield impacts at comparable speeds.

Safety performance of an experimental windshield with a thin, chemically tempered inner pane is compared with the standard windshield and other experimental windshields. The chemically tempered windshield has a penetration velocity of 35 mph compared with 26 mph penetration velocity for the standard windshield and has lower peak head accelerations than other types used in the experiments. The windshield tested produces a bulge on impact, which decelerates the head over a long distance with low accelerations. The bulge or pocket is lined with particles that are less lacerative than the standard annealed glass.

An improved windshield with a special, thin, plastic inner surface attached to the inner surface of a three layer windshield similar to those used in the United States minimizes lacerations from occupant impact to the windshield during a collision. The plastic coats the sharp edges of the broken glass preventing or minimizing laceration. It was evaluated by comparing its laceration performance with that of a standard windshield in simulated barrier crashes at velocities up to 65 km/h. No lacerations resulted from impact to the Securiflex windshield at Barrier Equivalent Velocities up to 65 km/h. Substantial laceration resulted at velocities above 20 km/h with the standard windshield. It is concluded that the Securiflex windshield essentially eliminates lacerations in the particular vehicle involved at velocities up to at least 65 km/h.

Children riding on the bed over the cab in campers can be injured in forward force collisions from striking the glazing material and/or being ejected through the opening. The two types of glazing commonly used are acrylic and laminated. A comparison of the performance of the two types of glazing in simulated forward force collisions at velocities up to 30 mph showed the acrylic material to pose threats of neck and back injury and the laminated material to result in lacerations. Ejections occurred with the acrylic that were not present with the laminated windshields when correct glazing techniques were used. With poor installation procedures, ejections occurred in both types of glazing materials. It is concluded that the best way to avoid injury is to prevent the child from riding in the over-the-cab bunk. If the child does ride there, his body axis should be positioned at an angle to the longitudinal axis of the vehicle.

A series of rear impact tests of varying severity was performed using a mini pick-up truck with an instrumented Hybrid III dummy at the driver position. Head, neck and chest loads were monitored. The severities of these loads from an injury standpoint were assessed using biomechanically based reference criteria that are particularly suitable for the Hybrid III. The glass Installation performed well as a head restraint. Glass fracture from head impact was achieved only when the glass was predamaged, with surface scratches on the outer (tensile) side. The amazing strength and flexibility of tempered glass and the dramatic reduction in strength caused by small surface scratches are demonstrated.