摘要：
—魏斯巴赫(Darcy-Weisbach)公式，曼宁(Manning)公式及谢才(Chezy)公式，
以管道的摩阻系数为其础，以塑料和钥筋混凝土两种管道为例，对
“动态
”
道工程最低成本时的常年运行费用
(30 年全寿命期间、残值为零)展开量化分析。
关键词：技术
比较 常年运行费用 量化分析 折现 工程成本 水力坡降
Focus On Data Analasis Of the Cost Of Operation in Comparing
Water Pipe Technical Economy
Abstract：By taking thep plastic pipe(PP) and reinforced pipe(PCP) for example，this paper
is to give a data analysis with a view to the cost of operation (COO,residual value is during its
30-year life span),
is worked out by the dynamic analysis method to compute the lowest
cost of water pipe project，with the employment of the eqcuations of thee:Darcy-weisbach,
Manning and Chezy and the hydralic friction coefficient as the base.As the flow and pipe
diameter(eg.Q=100,000m
3
/d，DN1000)being fixed,the hydralic gradient on the calculating
pipeline is analyzed order compare the difference of the COO and that of the static cost(maily
refferring to the cost of the pipe material)Prior to comparision,the difference should be discounted
(rate i=10%)into the cost of investment for a project.Secondly,to compare the carrying capacity of
pipe(CCOP) of the two kinds of pipe of the same diameter(DN1000)：provided,the outlay exceeds
the COO by 18.8%,the CCOP of the PP will be 35.7％ higher than the RCP；if the consumption is
equal to the COO,the CCOP will be 27.5％.When the CCOP ie defined as the
same(Q=100,000m
3
/d),the diameter of the PP will be smaller than that of the RCP.Also，there will
be reduction in the COO.
above said dynamic cost and static cost will have a great impact on
the cost of work,and are very likely to choice of a plan.
Keywords：comparing technical economy；cost of operation(COO)；data analysis；discount；
cost of work；hydraulic gradient
工程设计方案技术经济比较的实质，就是各方案所体现的经济效果，即能以最少的人力、
物力、财力消耗获得最佳的工程效益。为了正确评价方案经济效果的优劣，人们意识到
“资
金的时间价值
”以后，感觉到“动态分析法”比“静态分析法”更符合客观经济
。然而，采
用了正确的评价
，不等于评价出的结果就一定正确，因为人们往往对动态成本即常年运
行费用等经常性的成本并未做出具体的量化分析，只是作出定性的说明，凭经验估计其数值
的大小，缺乏足够的依据，准确度低。本文针对这
—情况，结合工程实例，采用“最低成本
法
”，以两种典型管道—塑性管与钢筋混凝土管为例，比较两方案的经济性。所谓“最低成本
法
”是“净现值法”的一种应用，对静态投资和常年运行费用折现计算，从所需费用的多少角
度来评价，以成本净现值小的方案的为优。为简化计算，笔者仅对占工程成本主要部份的管
道材料费、常年运行费用
(能耗)的折现值差额来进行比较，为方案的整体评价提供依据。
1 水力坡降计算公式的确定