平底蛋形断面隧洞正常水深直接计算方法  

Direct Calculation Method for Normal Depth of Egg-Shaped Section with Flat Bottom

作　　者：牛坤 华强 NIU Kun;HUA Qiang(Pingyi Country Water Conservancy Bureau, Pingyi 273300, China)

机构地区：[1]平邑县水利局,山东平邑273300

出　　处：《人民黄河》2019年第4期97-99,106,共4页Yellow River

摘　　要：平底蛋形断面具有施工相对简单、适应性强的特点,但断面形状较复杂,正常水深计算需要求解超越方程,计算过程繁琐且无法直接求解。利用面积分割法计算出普通平底蛋形断面的水力要素方程,得到3种典型断面的过水断面面积、湿周和水深方程。根据正常水深基本方程和优化拟合理论,推导出求解3种平底蛋形典型断面正常水深超越方程的直接简化计算公式,并进行公式精度分析。结果表明,直接简化计算公式具有形式简单、计算方便、精度高的特点,在适用范围内正常水深相对误差最大值仅为0.34%。The egg-shaped section with flat bottom has the characteristics of simple construction and strong adaptability, but its normal depth calculation formula must be derived from a transcendental equation which is a complicated process and difficult to solve with complex geometry. Using area segmentation method, the hydraulic factor equations of egg-shaped section with flat bottom were computed and then the area,wetted perimeter and depth of three typical sections were obtained. Based on the basic equation of normal depth and optimum matching theory, the direct and simplified formula was proposed to solve the normal depth transcendental equation of the three typical sections and their errors were analyzed and evaluated.The results show that the proposed simplified formulas are simple form, convenient calculation and high precision, and the maximum error of calculated normal depth is less than 0.34% in the practical range.

关 键 词：平底蛋形断面 水力要素 正常水深 直接计算 

分 类 号：TV133[水利工程—水力学及河流动力学]