The purpose of this article is to explore the design of compound interchange interweaving sections on expressways.During the research phase,based on the support of the literature research method,the classification and...The purpose of this article is to explore the design of compound interchange interweaving sections on expressways.During the research phase,based on the support of the literature research method,the classification and development of the interchange system,as well as the design forms of the compound interchange interweaving section,were analyzed.Subsequently,based on the case method,the design of the compound interchange interweaving section of the ShiWu and ShiBai expressways in Shiyan,Hubei Province,was discussed,and a design scheme and scheme comparison were proposed.It is hoped that this article can provide technical reference and ideas for China’s road and bridge engineering teams,ensuring that the design results can not only guarantee the normal passage of traffic on the North Intersection Expressway but also ensure the straight-line traffic capacity of the main highway under the background of dislocation intersection,achieving smooth and safe transitions between different expressways.展开更多
Mg-Zn-Zr series Mg alloys(ZK) are one of the most important commercial Mg alloys due to their good comprehensive mechanical properties. The phase equilibria of the Mg-Zn-Zr system at 400 ℃ covering the overall compos...Mg-Zn-Zr series Mg alloys(ZK) are one of the most important commercial Mg alloys due to their good comprehensive mechanical properties. The phase equilibria of the Mg-Zn-Zr system at 400 ℃ covering the overall composition range were investigated by X-ray diffraction and electron probe microanalyses on thirteen ternary alloys. Three ternary compounds, τ_1, τ_2 and τ_3, were detected to be thermodynamically stable at 400 ℃, and their homogeneity range was determined to be Mg_((7-17))Zn_((80-88))Zr_((4-6)), Mg_((15-22))Zn_((66-65))Zr_((9-16)) and Mg_9 Zn_(68)Zr_(23)(in at.%), respectively. Eight three-phase regions and four two-phase regions were observed. The maximum solubility of Mg in Zn_(22) Zr, Zn_(39) Zr_5 and Zn_3 Zr phases was measured to be 0.52, 0.37 and 0.99 at.%, respectively, while the solubility of Zr in MgZn_2 and Mg_2 Zn_3 phases is negligible. The isothermal section of the Mg-Zn-Zr system at 400 ℃ was then constructed based on the present experimental data.展开更多
文摘The purpose of this article is to explore the design of compound interchange interweaving sections on expressways.During the research phase,based on the support of the literature research method,the classification and development of the interchange system,as well as the design forms of the compound interchange interweaving section,were analyzed.Subsequently,based on the case method,the design of the compound interchange interweaving section of the ShiWu and ShiBai expressways in Shiyan,Hubei Province,was discussed,and a design scheme and scheme comparison were proposed.It is hoped that this article can provide technical reference and ideas for China’s road and bridge engineering teams,ensuring that the design results can not only guarantee the normal passage of traffic on the North Intersection Expressway but also ensure the straight-line traffic capacity of the main highway under the background of dislocation intersection,achieving smooth and safe transitions between different expressways.
基金The financial supports from the National Key Research and Development Plan (No. 2016YFB0701202)the National Natural Science Foundation of China (Grant No. 51771235)
文摘Mg-Zn-Zr series Mg alloys(ZK) are one of the most important commercial Mg alloys due to their good comprehensive mechanical properties. The phase equilibria of the Mg-Zn-Zr system at 400 ℃ covering the overall composition range were investigated by X-ray diffraction and electron probe microanalyses on thirteen ternary alloys. Three ternary compounds, τ_1, τ_2 and τ_3, were detected to be thermodynamically stable at 400 ℃, and their homogeneity range was determined to be Mg_((7-17))Zn_((80-88))Zr_((4-6)), Mg_((15-22))Zn_((66-65))Zr_((9-16)) and Mg_9 Zn_(68)Zr_(23)(in at.%), respectively. Eight three-phase regions and four two-phase regions were observed. The maximum solubility of Mg in Zn_(22) Zr, Zn_(39) Zr_5 and Zn_3 Zr phases was measured to be 0.52, 0.37 and 0.99 at.%, respectively, while the solubility of Zr in MgZn_2 and Mg_2 Zn_3 phases is negligible. The isothermal section of the Mg-Zn-Zr system at 400 ℃ was then constructed based on the present experimental data.