摘要
为了研究围岩温度对隧洞衬砌混凝土温度应力的影响规律,确保长距离输水隧洞的安全运行,以某水电站无压输水洞为研究对象,采用三维有限元温度场与徐变应力场仿真计算平台,对20、40、60、80℃围岩温度情况下的输水洞施工期及运行期进行仿真模拟。分析围岩温度对输水洞衬砌混凝土温度场和徐变应力场的影响,并研究了浇筑温度对高围岩温度隧洞衬砌混凝土应力场和损伤程度的影响。结果表明:围岩温度对输水洞衬砌混凝土温度场和温度应力场影响均较大,围岩温度每升高1℃,则衬砌混凝土的最高温度平均升高0.5℃,最大应力增大约0.033 MPa;浇筑温度每降低1℃,则其最大应力值减小约0.07 MPa。衬砌混凝土底板与边墙的交界处以及顶拱与边墙的交界处为隧洞衬砌结构的易损伤部位。降低浇筑温度,可以有效减小衬砌混凝土的损伤量,改善其应力状态,抑制损伤的发展。此研究可为类似高围岩温度隧洞工程提供参考。
In order to study the influence of surrounding rock temperature on the temperature stress of tunnel lining concrete and ensure the safe operation of long-distance water conveyance tunnels,the construction period and operation period of a non-pressure water conveyance tunnel under the surrounding rock temperature of 20℃,40℃,60℃and 80℃were simulated with the help of a 3D finite element platform for the simulation of temperature field and creep stress field.By comparing the temperature change curves and the stress at special time of the top arch,side wall and bottom plate,we analyzed the influence of surrounding rock temperature on the temperature field and creep stress field of the lining concrete of the water conveyance tunnel.At the same time,the influence of pouring temperature on the stress field and damage degree of high rock temperature lining concrete was studied.The results show that the temperature of the surrounding rock has great influence on the temperature field and temperature stress field of the lining concrete.When the rock temperature increases by 1℃,the maximum temperature of lining concrete increases by 0.5℃on average and the maximum stress increases by about 0.033 MPa.When the pouring temperature decreases by 1℃,the maximum stress decreases by about 0.07 MPa.The junction between the lining concrete base plate and the side wall,and that between the top arch and the side wall are the vulnerable parts of the tunnel lining concrete structure.Lowering the pouring temperature can effectively reduce the damage of the concrete,improve its stress state,and inhibit the development of the damage.This study can provide a reference for similar high surrounding rock temperature tunnel projects.
作者
司政
霍晓宇
辛兰芳
SI Zheng;HUO Xiaoyu;XIN Lanfang(Faculty of Water Resources and Hydroelectric Engineering,Xi’an University of Technology,Xi’an 710048,China;Beijing Hi-Tech Engineering Technology Co.,Ltd.,Beijing 100032,China)
出处
《水资源与水工程学报》
CSCD
北大核心
2021年第2期151-157,共7页
Journal of Water Resources and Water Engineering
基金
国家自然科学基金项目(51879217、51409207)。
关键词
输水洞
衬砌混凝土温度
围岩温度
温度应力
热损伤
water conveyance tunnel
lining concrete temperature
surrounding rock temperature
temperature stress
thermal damage
