華中科技大學學報(自然科學版) 2020, Vol. 48 Issue (12): 114-120 DOI10.13245/j.hust.201220
欄目:土木工程
水-溫作用下水工隧洞鋼筋混凝土襯砌開裂特性
摘要
考慮水工隧洞初次充水加壓過程和溫度場演化的時差性,采用塑性-損傷-接觸特征的多裂縫混凝土本構模型,結合某發電引水隧洞實例,研究水工隧洞鋼筋混凝土襯砌結構在內水壓與溫度場聯合作用下的開裂特征;同時針對內水水溫與外圍圍巖的溫度傳導過程,對水工隧洞初次充水加壓過程中不同加壓和溫降的疊加作用下襯砌開裂特征進行對比分析.數值分析結果表明:水工隧洞初次充水運行時,溫降的同步作用導致襯砌結構開裂時機提前,致使裂縫寬度的普遍增大和裂縫條數的減少;水-溫聯合作用下,提高隧洞充水加壓速度將增加集中裂縫的最大寬度,并對襯砌結構裂縫分布有較大影響;襯砌-圍巖之間的熱傳遞并不改變襯砌最大裂縫產生的位置,而會降低襯砌裂縫的最大寬度.
關鍵詞
水工隧洞
;鋼筋混凝土襯砌
;初次充水
;聯合作用
;裂縫寬度
Study on cracks of reinforced concrete lining of hydraulic tunnel under the combined action of water pressure and temperature load
Abstract
The plastic-damage-contact constitutive model for concrete was applied to study the cracking characteristics of the concrete lining of hydraulic tunnel,under the combined action of water pressure and temperature load,and the time difference between the first water-filling process and temperature field change was especially considered.And the combined effect of water-filling speed and temperature load for concrete lining was discussed by taking temperature conduction and mechanics characteristic of concrete lining into account.The result shows that the synchronous effect of temperature drop leads to crack earlier and generally increases the crack width and decreases the amount of cracks when the hydraulic tunnel operates with water for the first time.Under the combined action,increasing the velocity of filling tunnel increases the maximum width of concentrated crack and has a great influence on the crack distribution of lining structure.The thermal transmission between lining and surrounding rock has little effect on the crack position,but decreases the maximum crack width.
Keywords
hydraulic tunnel
; reinforced concrete lining
; first filling
; pressure-temperature action
; crack width
基金資助國家自然科學基金資助項目(51879207)
中圖分類號TV672.1
文獻標志碼A
文章編號1671-4512(2020)12-0114-07