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Study On Strength And Volume Stability Of Coral Mortar, Qingzong Xue

International Conference on Durability of Concrete Structures

No abstract provided.

Mechanical Properties And Microstructure Of High Strength Lc3 Pastes With Varying Limestone/Calcined Clay Ratios And Different Curing Conditions, Yemin Dong

International Conference on Durability of Concrete Structures

研究（抗施工蒸馏）石石和石榴石在淀粉胶系统（即0标准和低水印）下的水胶系统（即0标准和低水墨）X射线比、水量值水量-电子背基相关研究.61.25 .25.25.25.0.25.25.25.25.25.0.25.25.25.25.25.1.25.7.25.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.25.1.25.25.1.25.1.25.1.25.1.25.1.25.1 .25.1.25.1.25.1.25.1.25.1.25.0.0.0.0.0.0.0.00.0.0.1.25.1.25.1.25.1.25.1.25.0.0.0.00.0.0.0.0.0.0.0.0.0.0.0.0.0.00.0 .00.0.00.X射线比值、水量-电子显微镜相关研究测量值。早期的水泥水化程度小水的压合含煤量，降低了水泥石的。因此，需要采用合适的钙铝内容和体系以提高碳系统的性能。

Development And Properties Of Sulfate-Resistant And Corrosion-Inhibiting Admixtures, Tongwei Lu, Jie Zhang, Guisheng Cai, Linmao Wang, Xiangyang Guo

International Conference on Durability of Concrete Structures

Sulfate and chloride-induced corrosion of concrete and steel reinforcement are the most important causes of premature failure of durability of concrete structures. To prevent damage in concrete structures, the application of sulfate-resistant and corrosion-inhibiting admixtures has proven to be an effective method. In this study, a new type of corrosion-inhibiting admixtures including organic and special inorganic components are developed and the properties of mortar mixed with them was investigated. The results show that NC-CZ series of sulfate-resistant and corrosion-inhibiting admixtures have been successfully developed. The mortar with NC-CZ has good resistance to sulfate attack, whose corrosion resistance coefficient of mortar …

Study On The Effect Of Fly Ash On The Properties Of Potassium Magnesium Phosphate Cement, Bo Pang

International Conference on Durability of Concrete Structures

In this paper, the effect of fly ash on the setting time and mechanical properties of potassium magnesium phosphate cement is studied. The early hydration process of potassium magnesium phosphate cement was studied by TAM-Air, and the hydration products were analyzed by XRD. The results show that fly ash can effectively prolong the setting time and the compressive strength of the cement paste was decreased; The addition of fly ash would not change the phase composition of the hydration products of the potassium magnesium phosphate cement, which affect the hydration process, the amount of the hydration products and the degree …

Study On The Hydration Behaviour Of The Coral Sand Powder- Ground-Granulated Blast Furnace Slag-Portland Cement Ternary System, Renwang Nie, Haonan Wang, Zhuqing Yu, Xiaodong Shen

International Conference on Durability of Concrete Structures

Recently, the studies on the application of coral sand in concrete construction attracted wide attention, especially in China. Coral sand and coral sand powder (CSP) can be used as fine aggregate and mineral admixture in concrete, respectively. The main component of CSP is calcium carbonate (CaCO₃), up to 96%. However, the utilization of CSP in cement mortar will cause performance degradation. Ground-Granulated Blast Furnace Slag (BFS) be used to improve the property of CSP-Portland cement mortar. In this study, the coral sand powder-blast furnace slag-Portland cement (CSP-BFS-PC) ternary system had been used to produce cement paste and mortar. …

Study On Hydration Properties Of Grinded Tuff-Cement Cementitious Material System, Hao Wang

International Conference on Durability of Concrete Structures

The chemical composition and microscopic morphology characteristics of grinded tuff(GT) and fly ash(FA) were compared and analyzed in the paper. The chemical bound water content and hydration heat were tested for investigating the hydration properties of grinded tuff-cement cementitious material system (GTCS) and fly ash-cement cementitious material system (FACS). The results shown that, the chemical composition of GT was similar with that of FA, however the loss on ignition of the GT was obviously higher than FA. The microstructure of the GT particles was polygonal and irregular, while the microstructure of FA particles were mostly smooth spheres. The hydrated heat …

Numerical Investigation On Aggregate Settlement And Its Effect On The Durability Of Hardened Concrete, Qing-Feng Liu, Yuxin Cai

International Conference on Durability of Concrete Structures

Vibrating consolidation process is widely applied to field construction of cement concrete. However, high-frequency vibration can easily lead to the settlement of coarse aggregates (CAs) and then affects the durability of hardened concrete. This study has developed a 3-D concrete model to investigate the CA settlement caused by vibration and its effect on long-term chloride transport in concrete. Based on the proposed model, the influence mechanism of CA settlement on both chloride concentration distribution and initiation time of reinforcement corrosion is discussed in detail. The results indicate that due to the settlement, a more obvious fluctuation of chloride concentration along …

Study On Properties Of Fiber Reinforced Foam Concrete, Guofa Zheng

International Conference on Durability of Concrete Structures

No abstract provided.

Effect Of In-Situ Modification Of Poly-Dopamine On Workability And Frost Resistance Of Glass Fiber Reinforced Cement Materials, Pengfei Ma

International Conference on Durability of Concrete Structures

No abstract provided.

Particle Classification And Segmentation Of Hydrated Cement Based On Slic And Multivalued Data Processing, Zhen Wang

International Conference on Durability of Concrete Structures

Cement-based materials are widely used in production and life, but the production process has caused great harm to the environment. Moreover, the existing cement varieties will have various quality problems after several years of wind and sun exposure. Therefore, the study of high-quality cement is of great significance for energy conservation and emission and improving the quality and durability of cement. Many global teams are conducting relevant research, but they try to solve this problem from the perspective of pure materials, which requires a large number of physical and chemical experiments. In this paper, we try to solve this problem …

Influence Of Quartz Sand On The Properties Of Foam Concrete, Shi Yanyu

International Conference on Durability of Concrete Structures

The effect of 120-180 μm quartz sand on the mechanical properties, water absorption, thermal conductivity and porosity of foam concrete is studied in this paper. The results show that the addition of quartz sand can effectively enhance the compressive strength of foam concrete, but it will increase the thermal conductivity of foam concrete and reduce the thermal insulation performance of foam concrete. However, when the amount of quartz sand is 50%, foamed concrete has excellent comprehensive properties.

Investigation On The Properties Of Calcium Sulfoaluminate Cement Waterproof Repair Mortar Modified With Ethylene-Vinyl Acetate Powder, Dong Dong

International Conference on Durability of Concrete Structures

本文采用乙烯-醋酸乙烯酯（EVA）粉体和CSA水泥制备了防水修复砂浆，并对其水化和性能进行了研究。结果表明，EVA粉体延长了凝固时间，提高了防水修补砂浆的流动性，使其在实际工程中更容易应用。EVA粉提高了防水修复砂浆的不渗透性，降低了吸水性。虽然EVA粉降低了防水修补砂浆的抗弯强度和抗压强度，但它仍然符合JC/T 2381-2016标准对刚性修复砂浆的要求。EVA粉体降低了防水修复砂浆的收缩率，改善了界面过渡区和拉伸粘接强度、弯曲粘接强度等粘接性能。EVA粉末抑制CSA水泥的水合作用6 h，在3 d水化年龄时抑制作用消失。

Shrinkage And Durability Of Cement Mortars With Recycled Aggregates, Wencui Yang

International Conference on Durability of Concrete Structures

In recent years, the rapid growth of economy and urbanization process in China resulted in the massive construction and demolition wastes (C&DW). The reutilization of C&DW as recycled aggregates (RA) fully or partially to replace natural aggregates is an effective way to solve the environmental and economic problems caused by C&DW. The properties of cement mortars could be influenced by recycled fine aggregates due to their high absorption and the quantity of fine particles. This paper presents the main results of the research to explore the effect of recycled aggregate (RA) on shrinkage and durability properties of masonry mortars. Four …

Investigation On Structural Heritability And Durability Of High Sulfate Resistance Portland Cement Mortar Modified By Aluminum Salt, Jun Xu

International Conference on Durability of Concrete Structures

The essential hydration and hardened properties of high sulfate resistance Portland cement paste/mortar were investigated with Al₂(SO₄)₃ as admixture. Experiment results showed that that the addition of Al₂(SO₄)₃ promoted the hydration of HSRP cement pastes, and the hydration rate accelerated with the increase of the addition amount. The mechanical properties and chloride diffusion coefficient of cement mortar were obviously improved with 0.25% Al₂(SO₄)₃ addition . For instance, the compressive strength of AS0.25 cement mortars was 24.8% higher than AS0 samples and the chloride ion migration …

Mechanical And Thermal Insulation Properties Of Clay-Based Lightweight Concrete, Chuang Shi, Chuanlin Hu

International Conference on Durability of Concrete Structures

建材生产和住宅采暖将消耗大量能源并排放大量CO_2。在混凝土制备中，使用陶土制备具有优异隔热性能的轻质混凝土，并使用煅烧粘土代替部分波特兰水泥，可以大大降低能耗。本研究采用页岩陶土和陶砂分别作为粗骨料和细骨料制备轻质混凝土。首先，确定最佳体积砂比。然后，使用煅烧粘土和石灰石的剂量从30%，50%到70%。研究了煅烧粘土和石灰石含量对混凝土微观结构、力学性能和隔热性能的影响。结果表明，最佳体积砂比为50%。当煅烧粘土和石灰石的用量为30%时，强度在所有年龄段最高，28 d时强度可达33.6 MPa，比对照组高12%。当更换水平不断增加时，所有年龄段的实力开始下降。所制备的粘土基轻质混凝土的导热系数低至0.144 W/mK，表现出优异的保温性能。本研究制备的轻质混凝土具有较高的强度和优异的保温性能，具有良好的应用前景。

The Effect Of Initial Water Saturation On Freeze-Thaw Damage Of Submerged Mortar Materials, Siyuan Chen, Huigang Xiao

International Conference on Durability of Concrete Structures

An indispensable condition for the occurrence of the freeze-thaw (F-T) damage in unsaturated cement-based materials is that the specimens absorb water during the F-T process and reach a critical level of water saturation, which is influenced by the initial degree of water saturation (IDWS). However, the fast-freeze method commonly used in the laboratory does not reflect the effect of the IDWS on F-T damage. Thus, this study investigated the effect of different IDWS on the development of F-T damage in specimens to fill the gap in this research area. In this study, compressive strength tests were used to characterize the …

Nanoparticle Injection Technology For Remediating Leaks Of Co2 Storage Formation, Linfei Li

International Conference on Durability of Concrete Structures

No abstract provided.

Influence Of Biological Sulfuric Acid On Corrosion Mechanism Of Alkali-Activated Cement Concrete, 季 韬 教授

International Conference on Durability of Concrete Structures

生物硫酸对碱活化水泥混凝土腐蚀机理的影响

丁方硕、韬骥、潘伟杰

福州大学土木工程系

抽象的

讨论了不同浓度的生物硫酸对碱活化水泥混凝土（AACC）腐蚀的影响，并以化学硫酸为参考。AACC的质量和抗压强度、孔溶液的pH曲线和Ca ²⁺对其释放进行了研究，并通过 ESEM-EDS 和 XRD 揭示了 AACC 的腐蚀机理。结果表明，在不同浓度的化学硫酸和生物硫酸作用下，AACC的腐蚀产物主要是石膏。随着硫酸浓度的增加，AACC的失重率增加，AACC的抗压强度降低。石膏阻碍化学硫酸进入混凝土。然而，石膏为细菌提供了生存环境，细菌很容易渗透到混凝土中，加速了AACC的破坏。与化学硫酸相比，生物硫酸增加了AACC的质量损失率和抗压强度。

参考

荣H，Wu，C.，Ma，G.，Zheng，X.，和Liu，Z，2021。污水环境下混凝土微生物腐蚀研究进展。中国陶瓷学会学报，49（5）：988-999。

Scholz, F., 1997。微生物影响的材料腐蚀：科学和工程方面。固态电化学杂志，1（2）：181-181。

谢毅，林，X.，吉，T.，2019。普通硅酸盐混凝土与碱活化混凝土在生物硫酸侵蚀下的耐腐蚀机理比较。建筑和建筑材料，228（20）：1-12。

Frost Resistance And Pore Structure Properties Of Mortar Containing Air Entraining Agent Combined With Superabsorbent Polymer, Yanqun Xu, Qiang Yuan

International Conference on Durability of Concrete Structures

The air entraining effect of air entraining agent (AEA) is deeply affected by environment, which will further influence its function of improving frost resistance. To solve this problem, a strategy of using AEA combined with superabsorbent polymer(SAP) to improve the frost resistance of mortar was proposed in this study. Mass loss and relative dynamic elastic modulus of mortar were used to characterize frost resistance of mortar. Air void density, spacing factor, air void distribution and air content were measured to analyze its pore structure properties. The results verify that the combined use of AEA and SAP can improve the frost …

Carbonation Resistance Enhancement Of Cement Mortars With Recycled Plastics Using Ethylene-Vinyl Acetate And Nanosilica, Ahmed Al-Mansour, Qiang Zeng

International Conference on Durability of Concrete Structures

Carbonation resistance enhancement of cement mortars with recycled plastics using ethylene-vinyl acetate and nanosilica

Plastic has surpassed most of the man-made materials, and it has been accumulated as “waste” in the environment for several decades. Replacement of natural aggregates in concrete with recycled waste plastic (RWP) attracted great attentions in recent years due to the high potentials of recycling waste plastic. This employment of RWPs in concrete, however, was accompanied by reduction in mechanical properties and durability performances (e.g., carbonation) due to the poor interactions between RWP and cement matrix. The aim of this study is to lessen the mechanical …

The Transportation Of Corrosion Products In Cementitious Material Under Chloride-Rich Environment, Yuzhou Wang

International Conference on Durability of Concrete Structures

Corrosion products, forming on steel bar in cementitious material, can lead to concrete cracking. Clear the transportation of corrosion products is of great significance to predict corrosion-induced structural deterioration. This study investigates the corrosion products in steel-reinforced concrete specimen. By Raman spectroscopy and SEM method, the chemical constituents and micromorphology of corrosion products at steel-concrete interface as well as those inside the pore of cement paste are investigated. The proportion of corrosion products filling into the cement paste is determined by EDTA titration method. The results reveal that corrosion products diffuse in forms of ion in solution under chloride-rich environment, …

Research On Water Absorption And Frost Resistance Of Concrete Coated With Different Impregnating Agents For Ballastless Track Structure, Xin Ge, Yanbin Tan, Xiaowei Wang, Yongjiang Xie, Qinfei Li, Linxiang Li, Lu Yang, Zhongwei Feng

International Conference on Durability of Concrete Structures

In consideration of performance requirement of ballastless track concrete in cold regions of China, 3 types of commercially available impregnating agents were employed to research their effect on water absorption and frozen resistance of concrete, containing silanes, potassium silicate and osmotic curing agent. The results presented that coating silanes was the most effective on the reduction of water absorption among all employed impregnating agents, because of the most significant character change of concrete surface from hydrophilicity to hydrophobicity which could be proved by the contact angle test of concrete. The promotion on frozen resistance of concrete was not as significant …

Study On Corrosion Resistance Of Portland Cement-Calcium Sulphoaluminate Cement Binary System In A Sodium Chloride Environment, Shilin Song, Tao Xing, Yu Zhang, Jianzheng Wang, Xiaodong Shen, Ying Ma

International Conference on Durability of Concrete Structures

Portland cement is widely used in civil engineering. However, Portland cement-based materials are easy to be corroded by seawater in marine environment. Many research show the corrosion resistance of Portland cement mortar can be improved by add appropriate amount of mineral admixture.Sulphoaluminate cement have high strength and good corrosion seawater resistance. However, the short setting time and high hydration heat of sulphoaluminate cement limit its application in civil engineering.Portland cement-sulphoaluminate cement (PC-CSA) not only have high strength and corrosion resistance but also long setting time.In this work, the sulphoaluminate cement was used to partially replace Portland cement. The replacement level …

On The Role Of The Microstructure In The Deformation Of Porous Solids, Sansit Patnaik, Mehdi Jokar, Wei Ding, Fabio Semperlotti

Purdue University Libraries Open Access Publishing Fund

This study explores the role that the microstructure plays in determining the macroscopic static response of porous elastic continua and exposes the occurrence of position-dependent nonlocal effects that are strictly correlated to the configuration of the microstructure. Then, a nonlocal continuum theory based on variable-order fractional calculus is developed in order to accurately capture the complex spatially distributed nonlocal response. The remarkable potential of the fractional approach is illustrated by simulating the nonlinear thermoelastic response of porous beams. The performance, evaluated both in terms of accuracy and computational efficiency, is directly contrasted with high-fidelity finite element models that fully resolve …

Field-Test Performance Of Solid Oxide Fuel Cells (Sofc) For Residential Cogeneration Applications, Nicolas Paulus, Vincent Lemort

International High Performance Buildings Conference

No abstract provided.

A Heuristic Model Predictive Control Method To Activate The Energy Flexibility Of School Buildings, Navid Morovat, Andreas K Athienitis, José Agustín Candanedo

International High Performance Buildings Conference

No abstract provided.

Extraction As A Way To Improve The Performance Of Microchannel Condensers Using R134a, Jun Li, Pega Hrnjak

International Refrigeration and Air Conditioning Conference

No abstract provided.

Latent Thermal Energy Storage For Thermal Management Of Refrigerated Trucks, Michele Calati, Giulia Righetti, Claudio Zilio, Kamel Hooman, Simone Mancin

International Refrigeration and Air Conditioning Conference

No abstract provided.

Critical Impact Of Fin Thermal Conductivity In The Modeling Of Evaporator Under Frost Conditions, Antoine M. Parthoens, Samuel Gendebien, Vincent Lemort

International Refrigeration and Air Conditioning Conference

No abstract provided.

Utilization Of Ejector For Decrease Of Compressor Discharge Pressure In Hvac&R Applications, Md Muntasir Alam, Stefan Elbel

International Refrigeration and Air Conditioning Conference

No abstract provided.