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丹江口水利枢纽混凝土坝右岸１～右３等４个坝段向上游折转６０°，称右岸转弯坝段，在平面上呈向下游凸出的反拱形。运用初期，发现这几个坝段水平变形与其它直线坝段变形方向相反。其后增设监测项目、提高观测精度，全面监测坝体变形、坝基扬压力和坝踵接触面开合情况，经分析表明：转弯坝段＂反向＂变形并非全年发生，每年３～５月仍为正常变形，５～９月坝体升温，与两侧直线坝段热胀撑挤，产生了向下游的挠曲变形，与其他直线坝段相反，这一＂反向＂挠曲９月达最大值，同时坝踵基岩接触面有微小开裂，帷幕前扬压力加大。９月至次年２月热胀挤压力逐渐减小，变形又回复原状，坝踵裂缝逐渐闭合，扬压力降低。为消除坝体长期反复撑挤变形，避免坝踵周期性开裂，保证坝基防渗质量，今后当大坝加高时，应针对＂反向＂变形产生的原因进行有效的处理。建议对初期坝顶附近的灌浆横缝采用锯缝（钻成空缝）处理，下游坡加厚及坝顶加高新浇筑混凝土横缝填软垫层，以消除热胀撑挤作用，进行坝基渗控补强处理，并继续加强安全监测。
Danjiangkou Hydropower Project concrete dam right bank 1 ~ 3 3 dam bent upstream to 60 °, said the right bank turns dam segment, in the plane was convex downstream anti-arch. In the initial stage of application, it is found that the horizontal deformation of several dam sections is opposite to the deformation of other straight-line dam sections. After the establishment of monitoring projects to improve the accuracy of observation, the full monitoring of dam deformation, dam abutment pressure and the heel contact surface opening and closing situation, the analysis shows that: turning dam “reverse” deformation is not occurring throughout the year, March to May each year Is still normal deformation, dam body warming from May to September, with the thermal expansion and contraction squeeze of the linear dam on both sides, resulting in the deflection to the downstream. Contrary to other linear dam sections, this “reverse” deflection Up to the maximum, at the same time there is a slight crack in the contact surface of the base rock of the heel, and the pressure in the front of the curtain increases. From September to February, the thermal expansion and extrusion pressure gradually decreased, and the deformation returned to its original shape. The crack in the heel gradually closed and the uplift pressure decreased. In order to eliminate the long-term repeated distraction and deformation of the dam, to avoid periodic cracking of the dam heel and ensure the seepage prevention dam foundation quality, in the future when the dam is heightened, the reasons for the “reverse” deformation should be effectively dealt with. It is suggested that the grouting transverse seam near the initial crest should be treated with sawing (drilling into an empty seam), the thickening of the downstream slope and the height of the crest, and the pouring of the concrete transversely filled cushion to eliminate the thermal expansion and contraction, Control reinforcement treatment, and continue to strengthen safety monitoring.