以龙开口水电站为例，提出了预应力钢衬钢筋混凝土坝后背管结构的设计方案，并采用非线性有限元理论对背管结构进行了极限承载力分析。研究了坝后背管结构的应力分布规律，并将预应力钢衬钢筋混凝土坝后背管与普通钢衬钢筋混凝土坝后背管进行对比分析。研究成果表明：预应力钢衬钢筋混凝土坝后背管结构具有节省投资、避免开裂、耐久性好等优点，是一种值得广泛应用和推广的压力管道结构形式。

A design scheme of prestressed steel-lined reinforced concrete (RC) penstock laid on the downstream surface of dam is proposed, and the ultimate bearing capacity of the penstock is analyzed through nonlinear finite element theory. Longkaikou hydropower station is taken as a case study. The law of stress distribution of the penstock structure on the downstream surface of the dam is discussed. Prestressed steel-lined RC penstock is compared with common steel-lined RC penstock in terms of stress, concrete consumption, and steel consumption. Results show that prestressed steel-lined RC penstock on the downstream surface could save investment, avoid cracking, and is of good durability, thus is worth of wide application and promotion.