Journal of Jilin University(Engineering and Technology Edition) ›› 2021, Vol. 51 ›› Issue (5): 1734-1741.doi: 10.13229/j.cnki.jdxbgxb20200599

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Effect of hydration heat temperature and cracking mechanism of beam end in early stage of T⁃beam

Ying-xin HUI1,2,3(),Xiao-rong SUN1,Hong-yu WANG1,Chen GAO1   

  1. 1.School of Civil and Hydraulic Engineering，Ningxia University，Yinchuan 750021，China
    2.Ningxia Communications Construction Co. ，Ltd. ，Yinchuan 750002，China
    3.Ningxia Engineering Technology Research Center for Road Maintenance，Yinchuan 750002，China
  • Received:2020-08-10 Online:2021-09-01 Published:2021-09-16

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Abstract:

In order to avoid high hydration heat of precast concrete T beam during construction and maintenance， early vertical cracks appear at the beam end. Taking a 40-meter prestressed concrete T-beam as the research object， the mechanical properties of the concrete t-beam during the pouring process were monitored and tested. According to the measured results， a refined finite element model considering the early time-varying of the beam segment was established. And based on the above model， the evolution characteristics of hydration heat temperature field and the stress distribution law at the end of the beam during pouring process were studied. The results show that in the initial stage of concrete pouring of the 40-meter-span precast T-beam， the position near the beam end has a higher risk of cracking due to the rapid accumulation of temperature during the hydration process. In the area 2m～4m away from the beam end， the cracks are easy to penetrate through the web near the flange plate. It is recommended to control the mold-in temperature within 20 ℃， and adopt the method of optimizing the mixing ratio， reduce the amount of cement or use low-heat-of-hydration cement to reduce the heat of hydration and prevent cracking.

Key words: prestressed concrete T-beam, crack at the beam end, hydration heat, temperature field, stress field, finite element method

CLC Number: 

  • U441

Fig.1

Site diagram of web crack at prefabricated T beam end"

Fig.2

Layout of measuring points beam end"

Fig.3

Time-history curve of hydration heat temperature at relevant measuring points at 2 m and 4 m sections of prefabricated T beam ends"

Table 1

Temperature peak of prefabricated beam at each measuring point"

测点名称2 m截面峰值/℃4 m截面峰值/℃
测点1、342.940.9
测点4、543.843.0
测点7、946.044.4
测点11、1343.543.9
测点243.542.3
测点650.849.9
测点853.851.9
测点1058.956.2
测点1252.850.5

Table 2

Mechanical properties of prefabricated beam concrete at early ages"

龄期τ/df(cu,τ)/MPaf(t,τ)/MPa
113.51.32
329.32.20
536.62.55
741.42.78
1046.53.00
2861.33.60

Fig.4

Meshed finite element model"

Table 3

Comprehensive heat exchange coefficient of concrete surface"

文献风速/（m·s-1）部位

热交换系数/

（W·m-2·K-1）

［10］v顶板?=10.942+4v
腹板?=9.428+4v
底板?=7.514+4v

Table 4

Mixing proportion and thermal parameters of concrete"

项目水水泥砂石外加剂
比热/［kJ·（kg·℃）-1］4.190.460.700.69－

导热系数/

［kJ·（m·h·℃）-1］

2.164.4511.1310.50－
百分比/%5.7715.6329.6044.400.49

Fig.5

Time-history comparison of measured and calculated temperature at 2 m section of beam end"

Fig.6

Characteristic cross section temperature comparison diagram"

Fig.7

Time-history curve of first principal stress at measuring point 2 m and 4 m at beam end"

Fig.8

Temperature and time history at different temperature of casting concrete"

Table 5

Temperature peaks at different variable parameters"

模型编号入模 温度/℃温度 峰值/℃模型 编号水泥含量/（kg·m-3）温度 峰值/℃
1基准模型54.11#基准模型54.1
21550.42#36051.9
32556.73#37053.3
43058.74#39055.1
－－－5#40056.4
1 宿晓萍, 王清. 复合盐浸-冻融-干湿多因素作用下的混凝土腐蚀破坏[J]. 吉林大学学报: 工学版, 2015, 45(1): 112-120.
Su Xiao-ping, Wang Qing. Corrosion damage of concrete under multi-salt soaking, freezing-thawing and dry-wet cycles[J]. Journal of Jilin University(Engineering and Technology Edition), 2015, 45(1): 112-120.
2 张宁, 周鑫, 刘永健, 等. 基于点阵式测量的混凝土箱梁水化热温度场原位试验[J]. 土木工程学报, 2019, 52(3) :76-86.
Zhang Ning, Zhou Xin, Liu Yong-jian, et al. In-situ test on hydration heat temperature of box girder based on array measurement[J]. China Civil Engineering Journal, 2019, 52(3): 76-86.
3 戴公连, 岳喆. 混凝土箱梁早期温度测试与分析[J].武汉大学学报: 工学版, 2019, 52(2): 139-144.
Dai Gong-lian, Yue Zhe. Test and analysis of early temperature of concrete box girder[J]. Engineering Journal of Wuhan University, 2019, 52(2): 139-144.
4 顾斌, 陈志坚, 陈欣迪. 大跨径混凝土箱梁桥有效温度与应变的实测分析[J]. 吉林大学学报: 工学版, 2013, 43(4): 877-884.
Gu Bin, Chen Zhi-jian, Chen Xin-di. Analysis of measured effective temperature and strains of long-span concrete box girder bridge[J]. Journal of Jilin University(Engineering and Technology Edition), 2013, 43(4): 877-884.
5 Taysi N, Abid S R. Temperature distributions and variations in concrete box-girder bridges: experimental and finite element parametric studies[J]. Advances in Structural Engineering, 2015, 4(18): 469-486.
6 Wang Y B, Zhan Y L, Zhao R D. Analysis of thermal behavior on concrete box-girder arch bridges under convection and solar radiation[J]. Advances in Structural Engineering, 2016, 19(7): 1043-1059.
7 李昀. 预应力混凝土T梁裂缝成因分析与处理[J].铁道科学与工程学报, 2015, 12(2): 330-334.
Li Yun. Cause analysis and treatment of cracks in prestressed concrete T beams[J]. Journal of Railway Science and Engineering, 2015, 12(2): 330-334.
8 朱伯芳. 大体积混凝土温度应力与温度控制[M]. 北京: 中国电力出版社, 2012.
9 Zhu S Y, Cai C B. Interface damage and its effect on vibrations of slab track under temperature and vehicle dynamic loads[J]. International Journal of Non-Linear Mechanics, 2014, 58(1): 222-232.
10 彭友松. 混凝土桥梁结构日照温度效应理论及应用研究[D]. 成都: 西南交通大学土木工程学院, 2007.
Peng You-song. Studies on theory of solar radiation thermal effects on concrete bridges with application [D]. Chengdu: College of Civil Engineering, Southwest Jiaotong University, 2007.
11 Zhu J S, Meng Q L. Effective and fine analysis for temperature effect of bridges in natural environments[J]. Journal of Bridge Engineering, 2017, 22(6): 1-19.
12 汪建群, 方志, 刘杰. 大跨预应力混凝土箱梁水化热测试与分析[J]. 桥梁建设, 2016, 46(5): 29-34.
Wang Jian-qun, Fang Zhi, Liu Jie. Measurement and analysis of hydration heat of long span PC Box- girders[J]. Bridge Construction, 2016, 46(5): 29-34.
13 朱伯芳. 水工混凝土结构的温度应力与温度控制[M]. 北京: 水科电力出版社, 1976.
14 宋军, 石雪飞, 阮欣. 大体积混凝土热学参数识别的优化[J]. 吉林大学学报: 工学版, 2018, 48(5): 1418-1425.
Song Jun, Shi Xue-fei, Ruan Xin. Optimization of thermal parameter identification for mass concrete[J]. Journal of Jilin University(Engineering and Technology Edition), 2018, 48(5): 1418-1425.
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