Geometric graphing method for graphing vertical stadia envelope curves of concave vertical curves

Abstract

The present invention discloses a geometric graphing method for graphing vertical stadia envelope curves of concave vertical curves. The geometric graphing method comprises: summarizing completed longitudinal-section results; obtaining an eye-height line and an object-height line; selecting a stake mark of a start point; according to the Code for Design of Urban Road Engineering, deviating a perpendicular line of the stake mark of the start point from a first intersection point according to a set stadia length, enabling the deviated perpendicular line to intersect with the object-height line to obtain a second intersection point; connecting the first intersection point with the second intersection point through a straight line segment, wherein the straight line segment is a traveling stadia line of the stake mark of the start point; successively obtaining the stadia line corresponding to each set of stake marks according to precision requirements; graphing the stadia enveloping curve; and inserting a control object of the corresponding proportion according to the designed stake marks to visually reflect whether the control object shields the traveling stadia line. The geometric graphing method provided by the present invention is high in operability and applicability. The longitudinal sections of all positions under different traffic organization manners are precisely controlled, so that the engineering design is more flexible, convenient and economic, which is favorable for the popularization and the application of graphing stadia enveloping diagrams as an engineering design method.

Description

technical field [0001] The invention relates to a geometric drawing method of a line of sight envelope. In particular, it relates to a geometric drawing method for drawing a concave vertical curve vertical line of sight envelope. Background technique [0002] Sight distance is an important design index to ensure the safety of highway driving, and it is one of the compulsory indicators of highway engineering construction standards. The shortest driving distance that the car travels along the road during the period from when the driver finds an obstacle to when he decides to take some measures is called the sight distance. Therefore, each lane along the highway should have sufficient sight distance, so that the driver can detect potential dangers in time and make correct responses to ensure driving safety. The line-of-sight safety evaluation technology is an important part of the road safety guarantee technology. It is a formal line-of-sight inspection and evaluation of road...

AI Technical Summary

Problems solved by technology

For vertical curves, especially the inspection of the sight distance on the concave vertical curve of the underpass type interchange, it is not only necessary to check whether the horizontal sight distance meets the requirements, but also to check whether the headroom can meet the requirements of the driving sight distance. The test of sight distance has not yet provided a more effective test method

[0005] At present, the code has not given a clear calculation formula for the inspection of the vertical driving sight distance, and relevant scholars have also conducted research on this, and the analytical solution of the vertical driving sight distance has not yet been obtained

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