{"title":"Mesoscale numerical study of aggregate size in concrete by discrete element method","authors":"R. Zhu","doi":"10.21012/FC10.235426","DOIUrl":"https://doi.org/10.21012/FC10.235426","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122912990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Fibers, Distributed Net Reinforcement and Sharp Corners on Fracture and Size Effect in Concrete Structures","authors":"Z. Bažant","doi":"10.21012/FC10.237978","DOIUrl":"https://doi.org/10.21012/FC10.237978","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126975945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is known that the fatigue resistance of concrete decreases when it becomes saturated with water, and that its compressive strength increases at low temperature. However, there have been few systematic investigations of the influence of the environmental temperature and moisture conditions on the fatigue resistance of concrete. In the present study, static loading and fatigue tests were carried out on concrete cylinders to determine their fatigue resistance under compression. The results indicated that at room temperature, the static compressive strength decreased with increasing moisture content. In contrast, at low temperature, it increased with increasing moisture content. On the other hand, regardless of the temperature, the fatigue resistance decreased as the moisture content increased.
{"title":"Experimental study of ambient temperature and moisture conditions on fatigue resistance of concrete","authors":"Y. Koda","doi":"10.21012/FC10.235057","DOIUrl":"https://doi.org/10.21012/FC10.235057","url":null,"abstract":"It is known that the fatigue resistance of concrete decreases when it becomes saturated with water, and that its compressive strength increases at low temperature. However, there have been few systematic investigations of the influence of the environmental temperature and moisture conditions on the fatigue resistance of concrete. In the present study, static loading and fatigue tests were carried out on concrete cylinders to determine their fatigue resistance under compression. The results indicated that at room temperature, the static compressive strength decreased with increasing moisture content. In contrast, at low temperature, it increased with increasing moisture content. On the other hand, regardless of the temperature, the fatigue resistance decreased as the moisture content increased.","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133790831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cracking at early age of a massive reinforced concrete structure : case of the gusset of the VeRCoRs mock-up","authors":"J. Mazars","doi":"10.21012/FC10.234286","DOIUrl":"https://doi.org/10.21012/FC10.234286","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114390051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mechanical evaluation of 3D printable nano-silica incorporated fibre-reinforced lightweight foam concrete","authors":"S. Cho","doi":"10.21012/FC10.232696","DOIUrl":"https://doi.org/10.21012/FC10.232696","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124499837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper is aimed at the development of the physical, mechanical and fracture characteristics of cementitious materials during ageing. Three mortars which differed only in the water-cement ratio (w/c) were prepared for manufacturing of the test specimens intended for the experiments. All mortars were prepared using the standardized quartzite sand with the particle grain size distribution of 0−2 mm CEN 196-1, CEM I 42.5 R Portland cement (cement plant Mokrá, Czech Republic) and water. The reference w/c was set to the value of 0.5. To produce two other mortars, this ratio was reduced by approx. 5 and 30 %. This resulted in w/c ratio 0.47 and 0.35 respectively. All test specimens were not protected intentionally from drying during the whole time of measurement and were stored in laboratory at ambient temperature of 21 ± 2 °C and relative humidity of 60 ± 10 %. The results of the shrinkage, elastic, fracture and strength parameters determined within the time interval from 3 days to 2 years of ageing are summarized and discussed in the paper. The results of performed experiments were partially published within the conference DYN-WIND’17. This paper focuses especially on the evaluation of the results obtained after 2 years of specimens ageing and also provides a complex discussion of the results gathered during the whole time of ageing. The results show a crucial impact of the w/c on the final values of mechanical and fracture characteristics. The early-age and long-term characteristics were substantially influenced by the poor curing conditions.
本文旨在研究胶凝材料在老化过程中的物理、力学和断裂特性。制备了三种仅水灰比(w/c)不同的砂浆，用于制作用于实验的试件。所有砂浆均采用粒径分布为0 ~ 2mm的标准化石英砂CEN 196-1, CEM I 42.5 R波特兰水泥(mokr水泥厂，捷克共和国)和水配制。参考w/c设置为0.5。为了生产另外两种迫击炮，这一比例减少了大约。5%和30%。w/c比值分别为0.47和0.35。在整个测量过程中，所有试样都没有故意保护以免干燥，并在环境温度为21±2°C，相对湿度为60±10%的实验室中保存。本文总结和讨论了在3天至2年老化时间间隔内测定的收缩率、弹性、断裂和强度参数的结果。完成的实验结果部分发表在DYN-WIND ' 17会议上。本文特别着重于对2年后试件老化结果的评估，并对整个老化过程中收集的结果进行了复杂的讨论。结果表明，w/c对最终的力学和断裂特性值有重要影响。较差的固化条件对其早期龄期和长期性能有较大影响。
{"title":"Complex evaluation of the mechanical and fracture properties of cementitious materials with different water-cement ratio","authors":"B. Kucharczyková","doi":"10.21012/FC10.233083","DOIUrl":"https://doi.org/10.21012/FC10.233083","url":null,"abstract":"This paper is aimed at the development of the physical, mechanical and fracture characteristics of cementitious materials during ageing. Three mortars which differed only in the water-cement ratio (w/c) were prepared for manufacturing of the test specimens intended for the experiments. All mortars were prepared using the standardized quartzite sand with the particle grain size distribution of 0−2 mm CEN 196-1, CEM I 42.5 R Portland cement (cement plant Mokrá, Czech Republic) and water. The reference w/c was set to the value of 0.5. To produce two other mortars, this ratio was reduced by approx. 5 and 30 %. This resulted in w/c ratio 0.47 and 0.35 respectively. All test specimens were not protected intentionally from drying during the whole time of measurement and were stored in laboratory at ambient temperature of 21 ± 2 °C and relative humidity of 60 ± 10 %. The results of the shrinkage, elastic, fracture and strength parameters determined within the time interval from 3 days to 2 years of ageing are summarized and discussed in the paper. The results of performed experiments were partially published within the conference DYN-WIND’17. This paper focuses especially on the evaluation of the results obtained after 2 years of specimens ageing and also provides a complex discussion of the results gathered during the whole time of ageing. The results show a crucial impact of the w/c on the final values of mechanical and fracture characteristics. The early-age and long-term characteristics were substantially influenced by the poor curing conditions.","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134351452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fracture mechanics based design of reinforced concrete beams-An analytical study","authors":"F. Rama","doi":"10.21012/FC10.244962","DOIUrl":"https://doi.org/10.21012/FC10.244962","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132243266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The prediction of the Thermo-Hydro-Mechanical (THM) behavior of large buildings with a containment role (reservoirs, dams, nuclear vessels, etc.) is a critical step towards their risk assessment. In particular, their cracking implies a considerable loss of their structural tightness that needs to be controlled, monitored and, if necessary, repaired to ensure a safe operational environment. The difficulty of performing numerical predictive analyses is related to (a) the multiphasic and multi-physical nature of concrete (b) the large number of inputs to identify at the specimen and structural scales (c) the non-negligible and intrinsic material and load related uncertainties. All these aspects strongly affect our ability to foresee the structural response of large constructions; especially in terms of cracking and tightness. In this contribution, a global finite elements based stochastic methodology is proposed to allow physically representative and efficient non-intrusive probabilistic coupling of strongly nonlinear and numerically expensive THM calculations. To this aim (a) concrete cracking is modeled using a stochastic, local and energy regularized damage model accounting for size effects (b) concrete permeability is defined using a strain-based law (c) the spatial heterogeneity of properties is modeled using discretized and FE projected Random Fields (d) uncertainties propagation is computed using adapted Surface Response based methods. For the demonstration of this strategy’s efficiency and effectiveness, in terms of physical accuracy and cost optimization, a 1:3 scaled containment building named VeRCoRs is considered as an application. In particular, a complete probabilistic analysis of its dry air leakage rate (indicative of the whole structural performance) is achieved within a computational time of tens of days only. In general, such results can help during the decision-making process for the design, maintenance and risk assessment of large structures with a containment role based on a leakagerate-defined criterion under service loads. 1 Institute of Engineering Univ. Grenoble Alpes 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures FraMCoS-X G. Pijaudier-Cabot, P. Grassl and C. La Borderie (Eds)
具有围堵作用的大型建筑(水库、水坝、核容器等)的热-水-机械(THM)行为预测是其风险评估的关键步骤。特别是，它们的开裂意味着其结构严密性的相当大的损失，需要加以控制、监测，并在必要时进行修理，以确保安全的操作环境。执行数值预测分析的困难与(a)混凝土的多相和多物理性质(b)在试样和结构尺度上识别大量输入(c)不可忽略的和固有的材料和负载相关的不确定性有关。所有这些方面都强烈影响我们预测大型建筑结构反应的能力;特别是在开裂和松紧方面。在这一贡献中，提出了一种基于全局有限元的随机方法，以允许物理上具有代表性和有效的非侵入性概率耦合强非线性和数值昂贵的THM计算。为此，(a)使用考虑尺寸效应的随机、局部和能量正则化损伤模型对混凝土裂缝进行建模;(b)使用基于应变的规律定义混凝土渗透性;(c)使用离散化和有限元投影随机场建模属性的空间异质性;(d)使用适应的基于表面响应的方法计算不确定性传播。为了证明该策略在物理精度和成本优化方面的效率和有效性，我们考虑了一个名为VeRCoRs的1:3比例的密闭建筑作为应用。特别是，它的干空气泄漏率(指示整个结构性能)的完整概率分析是在几十天的计算时间内实现的。总的来说，这些结果可以帮助在设计、维护和风险评估的决策过程中，根据服务载荷下泄漏定义的标准，对具有遏制作用的大型结构进行评估。1工程大学研究所第十届国际会议混凝土和混凝土结构的断裂力学[j] . x G. Pijaudier-Cabot, P. Grassl和C. La Borderie(主编)
{"title":"Uncertainty propagation through Thermo-Hydro-Mechanical modelling of concrete cracking and leakage – Application to containment buildings","authors":"J. Baroth","doi":"10.21012/FC10.235507","DOIUrl":"https://doi.org/10.21012/FC10.235507","url":null,"abstract":"The prediction of the Thermo-Hydro-Mechanical (THM) behavior of large buildings with a containment role (reservoirs, dams, nuclear vessels, etc.) is a critical step towards their risk assessment. In particular, their cracking implies a considerable loss of their structural tightness that needs to be controlled, monitored and, if necessary, repaired to ensure a safe operational environment. The difficulty of performing numerical predictive analyses is related to (a) the multiphasic and multi-physical nature of concrete (b) the large number of inputs to identify at the specimen and structural scales (c) the non-negligible and intrinsic material and load related uncertainties. All these aspects strongly affect our ability to foresee the structural response of large constructions; especially in terms of cracking and tightness. In this contribution, a global finite elements based stochastic methodology is proposed to allow physically representative and efficient non-intrusive probabilistic coupling of strongly nonlinear and numerically expensive THM calculations. To this aim (a) concrete cracking is modeled using a stochastic, local and energy regularized damage model accounting for size effects (b) concrete permeability is defined using a strain-based law (c) the spatial heterogeneity of properties is modeled using discretized and FE projected Random Fields (d) uncertainties propagation is computed using adapted Surface Response based methods. For the demonstration of this strategy’s efficiency and effectiveness, in terms of physical accuracy and cost optimization, a 1:3 scaled containment building named VeRCoRs is considered as an application. In particular, a complete probabilistic analysis of its dry air leakage rate (indicative of the whole structural performance) is achieved within a computational time of tens of days only. In general, such results can help during the decision-making process for the design, maintenance and risk assessment of large structures with a containment role based on a leakagerate-defined criterion under service loads. 1 Institute of Engineering Univ. Grenoble Alpes 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures FraMCoS-X G. Pijaudier-Cabot, P. Grassl and C. La Borderie (Eds)","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132770755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Anglani, P. Antonaci, Susana I. Carillo Gonzales, Giorgia Paganelli, J. Tulliani
{"title":"3D printed capsules for self-healing concrete applications","authors":"G. Anglani, P. Antonaci, Susana I. Carillo Gonzales, Giorgia Paganelli, J. Tulliani","doi":"10.21012/FC10.235356","DOIUrl":"https://doi.org/10.21012/FC10.235356","url":null,"abstract":"","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"70 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133007093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fatigue behaviour in concrete and grout has become a very important mechanical behaviour to be studied further due to more sleek structures requiring higher performances and strength, such as onshore and offshore wind turbines. However, relatively few studies are available about fatigue behaviour and often contradictory. A series of monotonic and fatigue tests were performed to investigate the fatigue behaviour of ultrahigh strength grout under compression. Multiple stress levels were tested at two loading frequencies, 10Hz and 1Hz. The developments of strain and stiffness degradation were analysed for each test and show a typical three-step damage mechanism. At a higher frequency, some heating is observed within the specimen and the observations are made with thermocouples and infrared thermography. Since the fatigue testing is very time consuming, mostly when defining the S-N curve and endurance limit, an alternative method such as the selfheating method was used. This method is widely applied in materials such as steel [1], aluminium, composite materials or rubber-like materials, to define the endurance limit with only a few specimens based on the heating released during fatigue testing. To the authors knowledge, it has never been used in grout materials. Our experimental work on numerous specimens shows that the self-heating method might be an alternative method in order to predict the endurance limit for concrete and grouts. Erisa Myrtja, Olivier Rateau, Jerome Soudier, Evelyne Prat and Mohend Chaouche
{"title":"Strain development of high strength grouts under compressive fatigue loading and determination of fatigue properties from self-heating measurements","authors":"E. Myrtja","doi":"10.21012/FC10.235506","DOIUrl":"https://doi.org/10.21012/FC10.235506","url":null,"abstract":"Fatigue behaviour in concrete and grout has become a very important mechanical behaviour to be studied further due to more sleek structures requiring higher performances and strength, such as onshore and offshore wind turbines. However, relatively few studies are available about fatigue behaviour and often contradictory. A series of monotonic and fatigue tests were performed to investigate the fatigue behaviour of ultrahigh strength grout under compression. Multiple stress levels were tested at two loading frequencies, 10Hz and 1Hz. The developments of strain and stiffness degradation were analysed for each test and show a typical three-step damage mechanism. At a higher frequency, some heating is observed within the specimen and the observations are made with thermocouples and infrared thermography. Since the fatigue testing is very time consuming, mostly when defining the S-N curve and endurance limit, an alternative method such as the selfheating method was used. This method is widely applied in materials such as steel [1], aluminium, composite materials or rubber-like materials, to define the endurance limit with only a few specimens based on the heating released during fatigue testing. To the authors knowledge, it has never been used in grout materials. Our experimental work on numerous specimens shows that the self-heating method might be an alternative method in order to predict the endurance limit for concrete and grouts. Erisa Myrtja, Olivier Rateau, Jerome Soudier, Evelyne Prat and Mohend Chaouche","PeriodicalId":329531,"journal":{"name":"Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133526973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：