Simplified design method for highway easement curves

Abstract

The invention discloses a simplified design method for highway easement curves. The method comprises the steps of confirming a highway easement curve starting point, a highway easement curve terminal point and a highway easement curve starting point radius, a highway easement curve terminal point radius and highway easement curve parameters; setting a search line starting point as the highway easement curve starting point and a search line terminal point as the highway easement curve terminal point; calculating a maximum offset between a search line and a highway easement curve; and comparing the maximum offset with a preset accuracy control value to perform curve fitting. According to the simplified design method for highway easement curves, the design accuracy can be controlled accurately; fitting straight line or arc segments are few; control errors are calculated directly instead of being approximated iteratively, the speed is fast, and the efficiency is high while easement curves are drawn in mass; problems of difficulties in controlling calculation accuracy and calculating directly of parallel line drawing, relevant lengths and intersection and the like of easement curves are solved; and the problem that differences of chord arcs arranged on bridges on easement curves are difficult to accurately calculate is solved.

Description

technical field [0001] The invention belongs to the field of highway design and construction, and in particular relates to a simplified design method of highway transition curves, which is suitable for calculation and drawing of highway transition curves and offset lines thereof, and facilitates highway design and construction. Background technique [0002] The transition curve is a curve whose curvature continuously changes between a straight line and a circular curve, and between circular curves with different radii in the same direction. The current "Code for Design of Highway Alignment" (JTG D20-2006) stipulates that the clothoid is used as a transitional curve, so the clothoid is one of the important elements of the highway plane alignment. [0003] Clothoids are complex high-order continuous smooth curves. Its characteristic is that the radius of curvature r on the curve changes uniformly and decreases as the length of the curve l increases. That is to say, for two p...

AI Technical Summary

Problems solved by technology

According to the fitting line of the highway transitional curve, the design and calculation of the transitional curve are simplified; the precision of the transitional curve can be controlled according to the needs of highway design and construction; the calculation accuracy of the parallel line drawing of the transitional curve and its related length and intersection calculation can be solved Difficult to control and difficult to calculate directly; solves the problem that in the design of highway bridges, it is difficult to accurately calculate the chord difference of the bridge layout on the transition curve

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