Guideway Geometry for AGT Systems

A logical method of defining horizontal and vertical Automated Guideway Transit (AGT) guideway geometry is presented. Only geometric accelerations and jerk are considered, which are defined as those which a passenger feels if the guideway is smooth and rigid and the vehicle fully damped. No account is taken of vibrational effects. The interaction of the roll flexibility of the vehicle with the superelevation on curves is discussed and simplified expressions developed for design applications. A new horizontal transition curve is presented which is a refinement of the Mast equation and ensures continuity of unbalanced lateral acceleration at both ends of the curve for small and large spiral angles. Expressions are developed for transition lengths based on limitation on lateral jerk, vertical acceleration at superelevation buildup, and on rate of twist. These lengths are compared in a general way with those currently in use for highways and railroads. A new vertical transition curve, which ensures a gradual buildup of vertical accelerations is presented. By limiting the value of maximum acceleration, the length of the vertical curve is established.