沙漠重載鐵路槽型梁水化熱溫度監(jiān)測與分析

打開文本圖片集
中圖分類號:TB9;U239.5:U441 文獻標(biāo)志碼:A文章編號:1674-5124(2025)06-0097-09
Monitoring and analysis of hydration heat temperature of channel beam in desert heavy haul railway
LIU Yuyi1,LIU Mengfu2,LU Yihui2,LI Xiaodong2,JIN Tengfei2, ZHANG Xun1 (1.DepartmentofBridge Engineering,Southwest Jiaotong University,Chengdu 610031,China; 2.UAE Branch, China Civil Engineering Construction Corporation, Abu Dhabi , UAE)
Abstract: This study investigates the variation paterns of hydration heat temperature field and stress field during the construction of prestressed concrete channel beams,using a practical project, numerical simulation, and field testing. The findings are as folows: 1) Concrete temperature increases rapidly after pouring,then decreases gradually, eventually reaching a trend similarto the ambient temperature. 2) The upper flange of the web span experiences the highest temperature. Both measured and simulated maximum temperatures of 65.2°C and 70.2°C , respectively, occur around the 3Oth hour after pouring. 3) The temperature difference between the inner surface of the concrete at each measuring position remains within 25°C . The daily cooling rate exceeds the limit of in the early stage of cooling due to significant temperature fluctuations between day and night. 4) The fitting results are excellent.The average temperature difference at each measuring point ranges from 0.5 to 4.7°C ,and the time difference for the highest temperature remains within O to 4 hours when comparing measured and simulated results. 5) Simulation results reveal areas where the temperature-induced stress exceeds the tensile strength of concrete at the same age. Consequently,the channel beams areat risk of cracking due to temperature stress.To mitigate this, a well-designed temperature control plan should be implemented during the construction process.
Keywords: heavy haul railway; channel beam; hydration heat; temperature monitoring; temperature stress
0引言
槽型梁結(jié)構(gòu)具有橋下凈空大、建筑高度低、截面利用率高、降噪效果好等優(yōu)點[1],因此該類結(jié)構(gòu)越來越多地被利用到了城市軌道交通的建設(shè)當(dāng)中[2]。(剩余10841字)