Page 527 - Automotive Engineering Powertrain Chassis System and Vehicle Body

CHAP TER 1 6. 1 Terminology and overview of vehicle structure types

Fig. 16.1-16 Triangulated sports car structure (courtesy of Caterham Cars Ltd).

showed that the torsion stiffness can be increased by over skin performs the dual role of the body surface and
500 per cent as compared with the basic chassis frame. structure.
The contribution of the roll cage depended on (a) the This is the automotive version of aircraft ‘stressed
degree of triangulation in the roll cage, and (b) on how skin’ construction. It is very weight efficient.
well the roll cage was connected to the rest of the The pure monocoque car structure is relatively rare.
structure (i.e. on the continuity of load paths). Its widespread use is restricted to racing cars as shown in
Fig. 16.1-18. There are several reasons for this.
First, for the monocoque to work efficiently, it
16.1.2.2.4 Pure monocoque requires a totally closed tube. However, practical vehicles
The logical conclusion of the ‘closed box’ approach is the require openings for passenger entry, outward visibility,
‘monocoque’ (French: ‘single shell’). For this, the outer etc. This requires interruptions to the ‘single shell’ which

Fig. 16.1-17 Triangulated sports car structure with integrated roll cage (Roots et al. 1995 with original permission from TVR Ltd).

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