摘要
为了研究中美规范中公路涵洞水力计算的差异,以巴基斯坦某公路工程项目为实例,采用了中美规范的涵洞水力设计方法,对比分析了公路涵洞的布置参数,并主要分析计算了涵洞水力性能,确定了关键性的设计因素,最后推荐了公路涵洞水力设计方法。结果表明,中美方法的涵洞材料与形状不完全相同,在涵洞结构选取时,美国方法比中国方法多考虑了全寿命周期成本、原始河道及水中生物等因素;中美方法的水力状态存在对应关系,美国的水力计算方程是半经验半理论的,而中国的无压力式涵洞设计是以临界流理论为基础,半压力式和压力式涵洞则是以能量方程为基础;中国方法的水流状态具有较明确界限,美国方法则认为水流状态之间具有过渡阶段;中美方法计算结果差异原因主要包括设计流量、标准孔径大小及单位换算,排除上述影响因素,中美设计结果基本相同;中美规范中,进水口构造、水力粗糙度及设计流量均对水力性能有显著影响,美国方法比中国方法多考虑了进水口边缘类型对涵洞水力性能的影响,中美涵洞材料水力粗糙度对水力性能的影响趋势一致,中美方法中设计流量与涵前水深均呈正相关关系。最后推荐公路涵洞水力设计以中国方法为主,并建议结合美国规范中的全寿命成本分析、进水口类型水力计算等处理方式。
In order to study the difference of hydraulic calculations for highway culverts between China and US specifications,taking a highway engineering project in Pakistan for example,the layout parameters of highway culverts are contrastively analyzed by using the hydraulic design methods of highway culverts in China and US specifications.The hydraulic performance of culvert is mainly analyzed and calculated,and the key design factors are determined.Finally,the hydraulic design method of highway culvert is recommended.The result shows that(1)The materials and shapes of culverts of China and US are not the same.In the selection of culvert structure,the American method takes into account more factors such as life cycle cost,original river and aquatic organisms than Chinese method.(2)There is a corresponding relationship between the hydraulic states in Chinese method and that in American method.The hydraulic calculation equation of American is semi-empirical,while the Chinese design of non-pressure culverts is based on critical flow,and the partial pressure culverts and pressure culverts are based on the energy equation.(3)The flow states in Chinese method have a clear boundary,while the American method considers that there is a transition stage between the flow states.(4)The reasons for the difference between the calculation results of Chinese and American methods mainly include design discharge,standard aperture diameter and its unit conversion,and the design results of China and US are basically the same excluding the above factors.(5)In China and US specifications,the inlet structure,hydraulic roughness and design discharge have significant influence on hydraulic performance.Compared with China method,American method more considers the influence of edge type of inlet on the hydraulic performance of culvert.The influence trend of hydraulic roughness on the hydraulic performance is consistent for China and US.The design discharge and water depth in front of the culvert are both positively correlated for China and US.Finally,it is recommended that the hydraulic design of highway culverts should be based on the Chinese method,and combining with the life-cycle cost analysis and hydraulic calculation of inlet type in American specification.
作者
罗志刚
高英
陈凯
王慧
林俊
LUO Zhi-gang;GAO Ying;CHEN Kai;WANG Hui;LIN Jun(China Road&Bridge Corporation,Beijing 100011,China;School of Transportation,Southeast University,Nanjing Jiangsu 211189,China;National Key Practical Education Center of Road and Traffic Engineering,Southeast University,Nanjing Jiangsu 211189,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2021年第7期69-76,共8页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(51878168)
中国路桥“一带一路”项目(2017-zlkj-08)。
关键词
桥梁工程
规范对比
公路涵洞
进水口构造
水力粗糙度
设计流量
水力性能
bridge engineering
specification comparison
highway culvert
inlet structure
hydraulic roughness
design discharge
hydraulic performance
作者简介
罗志刚(1978-),男,江西南昌人,博士,高级工程师.(luozg@crbc.com)。
