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通过对汾河下游王庄至柴庄段河道特征和来水来沙特性分析，得出汾河在该段的河相关系、纵横向稳定系数、床沙质沿程组成和汾河该段的三种不同的河型，即王庄至石滩及襄汾县城至柴庄为山区型河流；石滩至洪洞县城为山区向平原过渡型河流；洪洞县城至襄汾县城为平原冲积性婉蜒河流。给出了婉蜒型河段河床纵比降与床沙质的数学表达式。分析了三种不同类型的河段的河床演变特性及影响该段河床演变的因素，得出了过渡型河段和婉蜒型河段的河床演变在纵向上表现为泥沙堆积和淤积，从１９５３～１９８９年，过渡型河段年堆积速度为３．３ｃｍ／ａ，婉蜒型河段年淤积速度为２．６ｃｍ／ａ；在横向变化上过渡型河段河槽变化保持在３００～５００ｍ，婉蜒型河流主槽宽约１００ｍ，自由演变，其摆幅宽度可达１５００ｍ。
Through the analysis of the characteristics of the rivers and the characteristics of incoming and outgoing water from the Wangzhuang to Chaizhuang sections of the lower Fenhe River, the relationship between the river system and the vertical and horizontal stability factors of the Fenhe River, the composition of the sediment along the Fenhe and the three Different types of river, that is, from Wangzhuang to Shitan and Xiangfen County to Chai Zhuang for the mountain-type rivers; rock beach to Hongdong County for the mountain to the plain transitional river; Hongdong County to Xiangfen County plain alluvial Wan River. The mathematical expressions of river bed vertical bed fall and bed sand quality in the meandering section are given. The characteristics of riverbed evolution and the factors influencing the river bed evolution of the three different types of river sections are analyzed. It is concluded that the riverbed evolution in the transitional and evanescent sections of the riverbed is characterized by sediment accumulation and siltation in the vertical direction. From 1953 ~ 1989, the annual accumulation velocity of transitional sections is 3.3cm / a, and the siltation velocity of Wanning section reaches 2.6cm / a in 1989; the variation of river channels in transitional sections of lateral changes remains at 300 ~ 500m, The main groove of the serpentine-shaped river is about 100m wide and free to evolve with a width of up to 1500m.