互通立交鼻端纵坡计算方法探讨

Discussion on Calculation Method of Longitudinal Slope at Nose of Interchanges

摘要:

互通立交的设计越来越标准化和规范化，但部分细节尚有欠缺，其中匝道鼻端纵坡接坡就是其中之一。面的主线、匝道平纵线元这样简单的工况，平均纵坡法、纵坡推算法具有较好的适应性，但是在主线平纵线元复杂时，其所依附的计算理论的假设已不存在，也就难以计算出精确接坡数值，尤其是设置附加路拱工况下。为指导互通立交的工程设计，采用“极限”对复杂工况下的接坡点纵坡进行推导，得到计算公式。借助当代计算机的强大计算能力，更好的服务于互通立交设计。

Abstract:

The design of interchanges is becoming more standardized and normalized, but some details are still lacking, in which the connection of longitudinal slope at the ramp nose is one of the details. The average longitudinal slope method and the longitudinal slope reckoning algorithm have good adaptability for the simple working conditions of mainline and ramp horizontal and vertical line elements. However, when the mainline horizontal and vertical line elements are complex, the assumption of the calculation theory attached to it no longer exists, so it is difficult to calculate the exact slope connection value, especially under the condition of setting additional road arches. To guide the engineering design of interchanges, the longitudinal slope of the connection point under complex working conditions is deduced by “limitation” to obtain the calculation formula. With the powerful computing power of contemporary computers, it can better serve the interchange design.