Cement and Concrete Research最新文献_第7页

Basic creep properties of hydrates in mature slag-based CEM II concretes: A micromechanical analysis 成熟渣基CEM II混凝土中水合物的基本蠕变特性：微观力学分析

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-12-05 DOI: 10.1016/j.cemconres.2024.107735

Maximilian Sorgner , Rodrigo Díaz Flores , Bernhard Pichler , Thomas Pilgerstorfer , Bernd Moritz , Christian Hellmich

{"title":"Basic creep properties of hydrates in mature slag-based CEM II concretes: A micromechanical analysis","authors":"Maximilian Sorgner , Rodrigo Díaz Flores , Bernhard Pichler , Thomas Pilgerstorfer , Bernd Moritz , Christian Hellmich","doi":"10.1016/j.cemconres.2024.107735","DOIUrl":"10.1016/j.cemconres.2024.107735","url":null,"abstract":"<div><div>The demand for accurate characterization of slag-based CEM II concretes is becoming increasingly important as the construction sector shifts towards eco-efficient materials. Here, the basic creep behavior of slag-based CEM II concretes is traced back to mixture-invariant hydrate properties. Therefore, an experimentally validated three-step micro-viscoelastic model for CEM I/OPC-concretes is complemented by a Powers-Acker-type hydration model for CEM II and extended towards long-term creep, temperature activation, and moisture sensitivity. This model is used for a strain rate-based, aging viscoelastic analysis of two creep tests on distinctively different CEM II concretes; revealing that the shear creep modulus of CEM II hydrates is half as large as the one of ordinary Portland cement hydrates. This makes slag-based CEM II concretes especially suitable for applications such as precast segmental tunnel linings, where a faster stress relaxation under displacement-controlled conditions is beneficial.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"189 ","pages":"Article 107735"},"PeriodicalIF":10.9,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142776560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pyroaurite-like phases (Mg-Fe3+ LDH) synthesis and solubility 类辉钼矿相（Mg-Fe3+ LDH）的合成及溶解度

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-12-05 DOI: 10.1016/j.cemconres.2024.107739

Ellina Bernard , Barbara Lothenbach , Rupert J. Myers , Marcus H.N. Yio

{"title":"Pyroaurite-like phases (Mg-Fe3+ LDH) synthesis and solubility","authors":"Ellina Bernard , Barbara Lothenbach , Rupert J. Myers , Marcus H.N. Yio","doi":"10.1016/j.cemconres.2024.107739","DOIUrl":"10.1016/j.cemconres.2024.107739","url":null,"abstract":"<div><div>This study explores different methods for precipitating carbonated Mg-Fe<sup>3+</sup> layered double hydroxides (LDHs) with Mg/Fe<sup>3+</sup> ratios ranging from 2 to 2.5. Two synthesis approaches were investigated: a) CO<sub>3</sub>-Mg-Fe<sup>3+</sup>-LDH co-precipitated directly from MgO, Fe(NO<sub>3</sub>)<sub>3</sub> and Na<sub>2</sub>CO<sub>3</sub> and b) NO<sub>3</sub>-Mg-Fe<sup>3+</sup>-LDH precipitated by adding NaOH to Mg(NO<sub>3</sub>)<sub>2</sub>-Fe(NO<sub>3</sub>)<sub>3</sub> solutions, followed by ion exchange with Na<sub>2</sub>CO<sub>3</sub> to form CO<sub>3</sub>-Mg-Fe<sup>3+</sup>-LDH. The solids were characterised using TGA, XRD and FTIR. For the co-precipitated samples in the presence of Na<sub>2</sub>CO<sub>3</sub>, the formation of carbonate-LDH was accompanied by ~10–30 wt% of hydromagnesite, while CO<sub>3</sub>-Mg-Fe<sup>3+</sup>-LDH modified from the NO<sub>3</sub>-Mg-Fe<sup>3+</sup>-LDH did not show any other Mg‑carbonates but contained Fe hydroxides, as evidenced by their brown coloration. All samples were re-equilibrated at 7, 20 and 50 °C. The solubility product (log Kso) was calculated from solution analysis, and preliminary thermodynamic data are presented. The findings provide insights into the stability and formation conditions of carbonated Mg-Fe<sup>3+</sup> LDH phases in carbonate-rich environments.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"189 ","pages":"Article 107739"},"PeriodicalIF":10.9,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142776419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of cement content in concrete by spatially resolved laser induced breakdown spectroscopy 空间分辨激光诱导击穿光谱法估算混凝土中水泥含量

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-12-05 DOI: 10.1016/j.cemconres.2024.107714

Tobias Völker , Friedrich M. Mensing , Sabine Kruschwitz

{"title":"Estimation of cement content in concrete by spatially resolved laser induced breakdown spectroscopy","authors":"Tobias Völker , Friedrich M. Mensing , Sabine Kruschwitz","doi":"10.1016/j.cemconres.2024.107714","DOIUrl":"10.1016/j.cemconres.2024.107714","url":null,"abstract":"<div><div>The cement content in concrete significantly influences critical properties such as durability, permeability, strength, and workability. Traditional methods for estimating the cement content face limitations. These include the need for comprehensive chemical and solubility knowledge, extensive sample preparation, and their time-consuming and destructive nature. This study investigates the application of laser-induced breakdown spectroscopy (LIBS) as an alternative method. It involves probing concrete samples with high spatial resolution and analyzing the resultant spectra. The methodology is first tested on mesoscale concrete models to assess limitations and inherent errors. Subsequently, the methodology is applied to actual concrete samples with varying cement content and aggregate size distributions. The results demonstrate a promising accuracy, with an average relative error of approximately 8%. This paper offers a comprehensive evaluation of the method’s advantages, limitations, and factors influencing its practical applicability in field conditions.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"189 ","pages":"Article 107714"},"PeriodicalIF":10.9,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142776422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative evaluation of laboratory methods for performance assessment of cementitious materials in wastewater networks: Biological and chemical tests versus field exposure 污水管网中胶凝材料性能评估的实验室方法的比较评价：生物和化学试验与现场暴露

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-30 DOI: 10.1016/j.cemconres.2024.107741

Alexandra Bertron , Cyrill Grengg , Matthieu Peyre Lavigne , Holger Wack , Gregor J.G. Gluth , Amr Aboulela , Vanessa Sonois , Tilman Gehrke , Florian Mittermayr

{"title":"Comparative evaluation of laboratory methods for performance assessment of cementitious materials in wastewater networks: Biological and chemical tests versus field exposure","authors":"Alexandra Bertron , Cyrill Grengg , Matthieu Peyre Lavigne , Holger Wack , Gregor J.G. Gluth , Amr Aboulela , Vanessa Sonois , Tilman Gehrke , Florian Mittermayr","doi":"10.1016/j.cemconres.2024.107741","DOIUrl":"10.1016/j.cemconres.2024.107741","url":null,"abstract":"<div><div>The biodeterioration of concrete elements in sewer systems and their repair is of significant economic and societal concern. However, the available test methods to assess the performance of cementitious materials under the relevant conditions are insufficiently validated. In the present study, two biological test methods and a standardised chemical test were applied to two sewer repair mortars and a reference mortar, and the performances of these materials were compared in a severely deteriorating sewer environment. In both biological tests, the induction period was considerably shorter than that of the field, and time-resolved recording of durability indicators enabled to determine deterioration rates in the steady-state regime, which compared reasonably well with each other and with the behaviour in the sewer environment. The chemical test does not allow to obtain a deterioration rate, and the observed relative performance differences of the mortars deviated from the results of the biological tests.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"188 ","pages":"Article 107741"},"PeriodicalIF":10.9,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142753009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of flow rate on spatio-temporal deterioration of concrete under flowing sulfate attack 流速对流动硫酸盐侵蚀下混凝土时空劣化的影响

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-28 DOI: 10.1016/j.cemconres.2024.107734

Fujian Yang , Zhihao Zhao , Yuan Liu , Man Li , Jinliang Song , Dawei Hu , Hui Zhou

引用次数: 0

Penetration test of sheet-like indenter for yield stress assessment of 3D-printed concrete 用于评估 3D 打印混凝土屈服应力的片状压头渗透试验

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-26 DOI: 10.1016/j.cemconres.2024.107728

Haoyu Lu, Lizhi Zhang, Junkai Wang, Zhaoxin Shi, Wei She, Wenqiang Zuo

{"title":"Penetration test of sheet-like indenter for yield stress assessment of 3D-printed concrete","authors":"Haoyu Lu, Lizhi Zhang, Junkai Wang, Zhaoxin Shi, Wei She, Wenqiang Zuo","doi":"10.1016/j.cemconres.2024.107728","DOIUrl":"10.1016/j.cemconres.2024.107728","url":null,"abstract":"<div><div>The evolution of early mechanical properties of 3D-printed concrete (3DPC) plays a crucial role in early constructability, while current methods face challenges on the tradeoff between the accuracy and feasibility of mechanical properties characterization. In this paper, we designed a sheet-like indenter configuration to quantitatively obtain the yield stress of fresh 3DPC. First, we show the typical force-depth curve of sheet-like indenters obtained during the penetration test and analyze the main factors affecting the penetration resistance at various regimes. Then, we derive the quantitative correlation between the yield stress and the force-depth curve based on numerical simulation. Our results show that the slipping phenomenon between the indenter side and the material leads to an underestimation of the yield stress compared to the standard compression test and cone-shaped indenter. We moreover propose a sheet-like indenter with surface roughness modification to obtain the accurate yield stress value, together with a formula for the yield stress calculation based on the force-depth curve. Finally, we assess the feasibility of the proposed approach, which can robustly predict fresh 3DPC with yield stresses in the range of 1–100 kPa.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"188 ","pages":"Article 107728"},"PeriodicalIF":10.9,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Reaction and microstructure development of one-part geopolymer for wellbore applications – An experimental and numerical study 用于井筒的单组分土工聚合物的反应和微观结构发展--实验和数值研究

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-26 DOI: 10.1016/j.cemconres.2024.107738

Mayank Gupta , Xiujiao Qiu , Mohamed Omran , Yun Chen , Mahmoud Khalifeh , Guang Ye

{"title":"Reaction and microstructure development of one-part geopolymer for wellbore applications – An experimental and numerical study","authors":"Mayank Gupta , Xiujiao Qiu , Mohamed Omran , Yun Chen , Mahmoud Khalifeh , Guang Ye","doi":"10.1016/j.cemconres.2024.107738","DOIUrl":"10.1016/j.cemconres.2024.107738","url":null,"abstract":"<div><div>This study focuses on the numerical modeling of the reaction and microstructure development of a one-part granite-based geopolymer, which is often used for carbon capture and storage (CCS) applications. This work extends the capabilities of GeoMicro3D to model one-part geopolymers containing different precursors and activators (solid and in solution). The model considers the particle size distribution of different solids and the real shape of particles to prepare the initial simulation domain. Further, the dissolution rates of different solids estimated from the experiments were used to model the dissolution of different elements in the pore solution. Subsequently, the model utilizes classical nucleation probability modeling coupled with thermodynamic modeling to estimate the precipitation of products in the microstructure. Experiments were performed to study the pore solution, reaction degree, and amount of products in the microstructure, which were further compared with the simulation results to check the rationality of the model.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"188 ","pages":"Article 107738"},"PeriodicalIF":10.9,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142718565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantitative relationship between microstructure of steel-concrete interface and chloride-induced corrosion rate of steel in unsaturated cementitious materials 钢-混凝土界面微观结构与氯化物诱导的非饱和水泥基材料中钢腐蚀速率之间的定量关系

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-25 DOI: 10.1016/j.cemconres.2024.107736

Zushi Tian, Xiaojuan Kang, Haodong Ji, Hailong Ye

{"title":"Quantitative relationship between microstructure of steel-concrete interface and chloride-induced corrosion rate of steel in unsaturated cementitious materials","authors":"Zushi Tian, Xiaojuan Kang, Haodong Ji, Hailong Ye","doi":"10.1016/j.cemconres.2024.107736","DOIUrl":"10.1016/j.cemconres.2024.107736","url":null,"abstract":"<div><div>While extensive evidence indicates that the porous microstructure of the steel-concrete interface (SCI) is the key factor contributing to early depassivation and expedited corrosion propagation of steel rebar, there remains a lack of quantitative relationship between the SCI microstructural parameters and corrosion rate of steel, particularly under unsaturated conditions. In this work, the effects of rebar arrangement direction (i.e., horizontal and vertical orientations), binder type (i.e., ordinary Portland cement and alkali-activated slag), presence of aggregate, and chloride content, on both the SCI and chloride-induced corrosion rate of steel were systematically investigated and quantified at different relative humidity levels. The results indicated that in comparison with Portland cement counterparts, the reaction products of alkali-activated slag fill the gap under the horizontally oriented steel rebars, favoring more densified SCI microstructure and better corrosion protection. Quantitative analysis reveals that in the unsaturated state, the corrosion rate of steel decreases more slowly in more porous SCI microstructure. An image-based model is proposed to quantitatively link SCI microstructure and corrosion rate of steel, which is applicable to both Portland cement and alkali-activated slag systems in saturated and unsaturated conditions.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"188 ","pages":"Article 107736"},"PeriodicalIF":10.9,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142696506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rheology dependent pore structure optimization of high-performance foam concrete 优化高性能泡沫混凝土的流变孔隙结构

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-25 DOI: 10.1016/j.cemconres.2024.107737

Dingqiang Fan , Chunpeng Zhang , Jian-Xin Lu , Ligang Peng , Rui Yu , Chi Sun Poon

{"title":"Rheology dependent pore structure optimization of high-performance foam concrete","authors":"Dingqiang Fan , Chunpeng Zhang , Jian-Xin Lu , Ligang Peng , Rui Yu , Chi Sun Poon","doi":"10.1016/j.cemconres.2024.107737","DOIUrl":"10.1016/j.cemconres.2024.107737","url":null,"abstract":"<div><div>Foam concrete encounters a fundamental challenge in balancing lightweight and high strength. Pore optimization is the key to address this problem. This study starts with rheology control to optimize the pore structure of foam concretes, thereby designing high-performance foam concrete (HPFC). X-ray computed tomography was employed to explore the relationship between rheology and pore characteristics, revealing the corresponding control mechanisms. The findings indicated that rheological parameters, particularly viscosity, significantly influenced pore size, uniformity, sphericity, fractal dimension and connectivity. Therefore, there was an optimal viscosity range (1.30 ± 0.15 Pa·s) for achieving the desirable pore structure. Mechanical analysis demonstrated that the viscosity could impact the balance of the added foams under dynamic and static conditions via drag force, resulting in changes to the pore structure. After pore optimization, the HPFCs exhibited high compressive strength (2–3 times higher than normal foam concrete at an equal density) and excellent durability comparable to high-performance concrete.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"188 ","pages":"Article 107737"},"PeriodicalIF":10.9,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142696507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Reactive transport modelling of autogenous self-healing in cracked concrete 裂缝混凝土自生自愈的反应传输模型

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2024-11-21 DOI: 10.1016/j.cemconres.2024.107733

Daniel Lahmann, Sylvia Keßler

引用次数: 0