<正>宁（南京）淮（淮安）高速公路南京段的花旗营高架桥，跨越津浦铁路复线、宁启铁路和104国道。针对桥梁需多次跨越铁路、公路且结构特殊、架设困难等问题。通过局部改造架桥机，采用钢套箍牛腿结构加宽盖梁等多种措施保证了施工安全。

On the basis of analyzing and investigating the plots and stem analysis of poplar, the growth and yield models of poplar were established. Based on the growth and yield models, the optimum cultivation patterns of poplar plantations for every site index and various cultivation objectives were obtained by using method of dynamic economic evaluation. The results showed that the optimum patterns of cultivating middle woods and small logs should control planting density about 2500tree/hm2 and cutting age about 14～15 a in lower discount rate (3%). The net present value (NVP) was respectively increased 1982.41～31243.33yuan/hm2 and the inner revenue rate (IRR) was respectively increased 4.1%～9.3% than those conventional cultivation patterns, which felling age were 7～8a. The incomes can get from poplar plantation for cultivating large timber in the conditions of the site index equal or higher to 16 and planting density about 208～625tree/hm2 and cutting age about 14～22a. The optimum patterns of cultivating middle woods and small logs should control planting density about 2500tree/hm2 and cutting age about 9～12a in discount rate equal to 7%, the NVP was respectively increased 482.22～12413.07yuan/hm2 and IRR was respectively increased 5.2%～11.4% than those conventional cultivation patterns. The optimum cultivation patterns of cultivating large timber should control the planting density about 208～625tree/hm2 and cutting age about 16～22a. The optimum patterns of cultivating middle woods and small logs should control planting density about 2500tree/hm2 and cutting age about 8～9 a in discount rate equal to 12%, the NVP was respectively increased 1171.36～4025.03yuan/hm2 and IRR was respectively increased 3.1%～8.6% than those conventional cultivation patterns. These studies can provide technical references for cultivation and management of poplar plantation.