浅谈污水管道设计充满度的确定

DETERMINATION OF PROPORTIONAL DEPTH OF SEWER PIPE

污水管道的设计以往仅根据设计流量来估算管径,然后根据《室外排水设计规范》选择充满度来确定管径和底坡,或者先确定管径,然后再推求充满度和底坡.这样有可能造成浪费或者不能保证瞬时冲击流量的通过.本文介绍了根据水力学原理推导过载系数与充满度的函数式来计算在一定过载能力下的充满度.还列出充满度与过载系数关系表供设计选用,并举例说明.

Generally the diameter of sewer pipe was designed as follows: to estimate the diameter by designed flowrate and then to select the proportional depth (PD) according to the 'Design Standard of Outdoor Sewer System' and finally to determine the gradient and diameter of the pipe, or select the PD and gradient by the estimated diameter. By these steps excessive safety or insufficient capacity for the instantaneous peak flow rate may be caused. A new way based on the hydraulic principle to calculate the overloaded coefficient for defined overloaded capacity by the function of the PD and the overloaded coefficient is presented in this paper and some data stating the relationships between PD and the overloaded coefficient are listed with practical examples.