Influence of the Supplementary Cementitious Materials on the Dynamic Properties of Concrete

2014 ◽  
Vol 660 ◽  
pp. 162-167
Author(s):  
Elbachir Elbahi ◽  
Sidi Mohammed El Amine Boukli Hacene
Keyword(s):  
Dynamic Modulus ◽  
Dynamic Properties ◽  
Construction Materials ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Natural Pozzolan ◽  
Frequency Method ◽  
Concrete Mixtures ◽  
And Control ◽  
Non Destructive

The resonance frequency method is one of many non-destructive tests which allow us to evaluate construction materials. It was used to determine the dynamic properties of concrete, required in structures design and control, also considered as the key elements for materials dynamic. In this study, we chose a non-destructive approach to quantify-in laboratory-, the influence of adding “crushed limestone” and “natural pozzolan” on local concrete’s dynamic characteristics. However, several concrete mixtures have been prepared with limestone aggregates. The experimental used plan, allowed us to determine the dynamic modulus of elasticity, the dynamic modulus of rigidity of different formulated concretes.

scholarly journals Performance of Beting Bamboo (Gigantochloa Levis) as Partial Replacement for Coarse Aggregate in Concrete

2021 ◽  
Vol 920 (1) ◽  
pp. 012014
Author(s):  
R M K Tahara ◽  
M H Hasnan ◽  
N Z N Azizan
Keyword(s):  
Coarse Aggregate ◽  
Construction Materials ◽  
Environmental Issues ◽  
Cementitious Materials ◽  
Natural Fibre ◽  
Supplementary Cementitious Materials ◽  
Partial Replacement ◽  
Concrete Mixtures ◽  
Concrete Production ◽  
Alternative Materials

Abstract Conventional construction materials are considered as exploitation to natural resources. Thus, numerous alternative materials using natural or waste materials are proposed for concrete production as a response for greener, renewable and biodegradable environments with regard to sustainability. Natural fibre such as bamboo has been rapidly proposed for many applications especially for concrete production in construction. In order to tackle the environmental issues and focusing on sustainability, natural fibre of Beting bamboo is proposed for partial replacement used as supplementary cementitious materials. Current study investigates the partial replacement of coarse aggregate with Beting bamboo in concrete mixtures. The outcome of the study discovers that through the mix design, replacing 5% by weight of Beting bamboo is an ideal % to achieve concrete mixture for structural and nonstructural application. However, with the increase % of Beting bamboo for partial replacement, the strength of the concrete gradually decreased.

Performance of Impure Calcined Clay as a Pozzolan in Concrete

2020 ◽  
pp. 036119812095314
Author(s):  
Khashayar Jafari ◽  
Farshad Rajabipour
Keyword(s):  
Portland Cement ◽  
Drying Shrinkage ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Natural Pozzolan ◽  
Quartz Content ◽  
Calcined Clay ◽  
Air Content ◽  
Sand And Gravel

Supplementary cementitious materials (SCMs) are natural or industrial by-product materials which are used to improve the performance, durability, and sustainability of concrete mixtures. Motivated by the recent reports on shortage of conventional SCMs, impure calcined clays (CCs) are receiving attention as abundant alternative pozzolans for concrete. In this study, a clay slurry resulting from washing aggregates in a commercial sand and gravel pit was investigated. This source clay was dried and calcined, and the properties and pozzolanic performance of the resulting CC was evaluated. It was observed that despite having a large (>50%wt.) inert quartz content, the CC met all ASTM C618-19 (AASHTO M295) requirements for natural pozzolan. A pavement-grade concrete mixture containing 20%CC as a cement replacement (by weight) produced desired workability and fresh and hardened air content. Strength development was slightly below the control. The use of CC improved the durability of concrete with respect to chloride penetration, alkali–silica reaction, and drying shrinkage in comparison with a control (100% Portland cement) mixture. In addition, ternary limestone-calcined clay–cement and slag-calcined clay–cement mortar mixtures showed excellent strength development while replacing nearly 50% of the Portland cement.

Improving the Durability of High Early Strength (HES) Concrete Patching Materials for Concrete Pavements

2020 ◽  
Vol 2674 (8) ◽  
pp. 12-23
Author(s):  
Cameron Wilson ◽  
W. Jason Weiss
Keyword(s):  
Cement Content ◽  
Autogenous Shrinkage ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Concrete Pavements ◽  
Shrinkage Cracking ◽  
Concrete Mixtures ◽  
Water To Cement Ratio ◽  
Early Strength

High early strength (HES) concrete patching materials are increasingly used to repair damaged pavements. The use of HES concrete enables the repaired pavement to be opened to traffic shortly after the repair has been installed; for example, opening pavements to traffic 4–6 h after the concrete is placed is becoming more common. HES concrete mixtures are typically designed with a low water-to-cement ratio and a high cement content; they contain accelerating admixtures and limited supplementary cementitious materials. As a result, these HES patches may be susceptible to self-desiccation, causing autogenous shrinkage and early age cracking. Self-desiccation can lead to reduced hydration, limited strength gain, and overestimation of strength development in maturity-based predictions. The objectives of this study are threefold. First, the paper will illustrate how self-desiccation can lead to the premature cessation of hydration and increased potential for shrinkage cracking. Second, the paper will illustrate how maturity-based predictions can be modified to account for self-desiccation. Third, internal curing is discussed as a way to mitigate self-desiccation and shrinkage ultimately improving the performance of HES concrete patching materials.

Effect of Aggregate Max Size on the Rheological Properties of Self Consolidating Concrete

2020 ◽  
Vol 853 ◽  
pp. 193-197
Author(s):  
Samer Al Martini ◽  
Ziad Hassan ◽  
Ahmad Khartabil
Keyword(s):  
Blast Furnace Slag ◽  
Aggregate Size ◽  
Maximum Size ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Self Consolidating Concrete ◽  
Granulated Blast Furnace Slag ◽  
Concrete Mixtures ◽  
Time Period ◽  
Furnace Slag

The effects of aggregate size and supplementary cementitious materials (SCMs) on the rheology of self-consolidating concrete (SCC) were studied in this paper. Two main concrete mixtures with different maximum aggregate sizes were prepared and investigated. The first mix had a maximum size aggregate of 5 mm and the second mix was with 20 mm max size aggregates. All mixes incorporated different dosages of Ground granulated blast furnace slag (GGBS). The rheology of all mixes investigated was measured over 2 hour time period. It was found that the size of aggregates and GGBS dosage have influence on the yield stress of studied concrete mixes.

scholarly journals Long-term performance of sustainable pavements using ternary blended concrete with recycled aggregates

2021 ◽  
Author(s):  
Gilson Lomboy ◽  
Douglas Cleary ◽  
Seth Wagner ◽  
Yusef Mehta ◽  
Danielle Kennedy ◽  
...  
Keyword(s):  
Portland Cement ◽  
Cementitious Materials ◽  
Recycled Concrete ◽  
Supplementary Cementitious Materials ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Concrete Aggregates ◽  
Concrete Mixtures

Dwindling supplies of natural concrete aggregates, the cost of landfilling construction waste, and interest in sustainable design have increased the demand for recycled concrete aggregates (RCA) in new portland cement concrete mixtures. RCA repurposes waste material to provide useful ingredients for new construction applications. However, RCA can reduce the performance of the concrete. This study investigated the effectiveness of ternary blended binders, mixtures containing portland cement and two different supplementary cementitious materials, at mitigating performance losses of concrete mixtures with RCA materials. Concrete mixtures with different ternary binder combinations were batched with four recycled concrete aggregate materials. For the materials used, the study found that a blend of portland cement, Class C fly ash, and blast furnace slag produced the highest strength of ternary binder. At 50% replacement of virgin aggregates and ternary blended binder, some specimens showed comparable mechanical performance to a control mix of only portland cement as a binder and no RCA substitution. This study demonstrates that even at 50% RCA replacement, using the appropriate ternary binder can create a concrete mixture that performs similarly to a plain portland cement concrete without RCA, with the added benefit of being environmentally beneficial.

scholarly journals Monitoring and diagnosis of historical masonry buildings and future perspective = Monitoreo y diagnóstico de edificios históricos de mampostería y perspectiva futura

2021 ◽  
Vol 4 (1) ◽  
pp. 44
Author(s):  
Adolfo Preciado ◽  
Fabiola Colmenero
Keyword(s):  
Dynamic Properties ◽  
Construction Materials ◽  
Experimental Tests ◽  
Future Perspective ◽  
Historical Buildings ◽  
Vertical Loading ◽  
Thermal Cameras ◽  
Nuevas Tecnologías ◽  
Historical Masonry ◽  
Non Destructive

AbstractHistorical buildings still existing in different parts of the world were constructed with unreinforced masonry and have an acceptable capacity to transmit vertical loading, but they are very vulnerable against horizontal loading induced by earthquakes. In order to protect these buildings belonging to the patrimony of the humanity from this hazard, we need to understand the construction materials, structural elements and loading transmission mechanism. Moreover, to rehabilitate or retrofit them, it is necessary to develop an understanding process of the structure though monitoring and in-situ/laboratory experimental tests to stablish a diagnosis. The structural monitoring campaigns are helpful to investigate the mechanical and dynamic properties of the building. The use of installed thermal cameras and micro-sensors at strategic parts of the historical buildings represent a very interesting and non-destructive option to measure different parameters constantly and for long periods of time. The present paper aims at briefly describing the different involved processes in the monitoring and structural diagnosis of historical buildings which is fundamental in order to preserve them against the effects of earthquakes by means of rehabilitation works and strengthening. Moreover, it is presented a future perspective about non-destructive and non-invasive experimental tests and diagnosis with the use of new technologies.ResumenLos edificios históricos que aún existen en diferentes partes del mundo fueron construidos con mampostería no reforzada y tienen capacidad aceptable para transmitir cargas verticales, pero son muy vulnerables ante cargas laterales inducidas por sismos. Para proteger de esta amenaza a estas edificaciones que forman parte del patrimonio de la humanidad, debemos de entender los materiales constructivos, elementos estructurales y su mecanismo de transmisión de cargas. Para decidir entre rehabilitar o reforzar, se debe de realizar un proceso de entendimiento de la estructura a través de un monitoreo y pruebas experimentales en sitio y en laboratorio que permitan generar un diagnóstico. Los monitoreos estructurales sirven para investigar sus propiedades mecánicas y dinámicas. El uso de cámaras térmicas y micro-sensores en puntos estratégicos de los edificios históricos representan una opción muy interesante y no destructiva para medir diferentes parámetros de forma constante y por largos periodos de tiempo. El presente artículo tiene como objetivo describir de forma puntual los diferentes procesos involucrados en el monitoreo y diagnóstico estructural de edificios históricos que resulta fundamental para poder conservarlos ante los efectos de los sismos por medio de trabajos de rehabilitación y refuerzo. Además, se presenta una perspectiva futura sobre pruebas experimentales y diagnósticos no destructivos ni invasivos con el uso de nuevas tecnologías.

scholarly journals Development and Guidance of Green Concrete for Leed™ Applications

2010 ◽  
Vol 5 (4) ◽  
pp. 111-120
Author(s):  
John T Kevern
Keyword(s):  
Green Building ◽  
Cementitious Materials ◽  
Recycled Concrete ◽  
Supplementary Cementitious Materials ◽  
Recycled Aggregate ◽  
Strength Development ◽  
Concrete Aggregate ◽  
Total Contribution ◽  
Recycled Materials ◽  
Concrete Mixtures

As green building rating systems such as LEED™ become more popular, the use of recycled materials in construction is increasing. Concrete can be produced with significant quantities of supplementary cementitious materials or recycled aggregate materials. However, modifying concrete mixture proportions for improved recycled content credits also impacts strength and long-term durability. Without properly understanding the effects recycled materials have on concrete, greener concrete can be less desirable from a lifecycle perspective from poor durability. This research investigates the impacts different types and quantities of supplementary cementitious materials and recycled concrete aggregate have on strength development and concrete durability, specifically deicer scaling. Improvements to deicer scaling resistance were investigated using a novel soybean oil sealer. The concrete mixtures were also evaluated within the LEED™ recycled materials criteria for selection based on economy and total contribution value. Considerations are included to assist designers in the selection of greener concrete mixtures for appropriate applications.

Experimental Assessment Techniques for the Dynamic Properties of Concrete

2017 ◽  
Vol 21 ◽  
pp. 226-233
Author(s):  
Mihai Sergiu Stratulat ◽  
Oana Mihaela Banu ◽  
Ana Maria Toma ◽  
Petru Mihai ◽  
Ionuț Ovidiu Toma
Keyword(s):  
Dynamic Properties ◽  
Measurement Techniques ◽  
Construction Materials ◽  
Rubberized Concrete ◽  
Destructive Testing ◽  
Recycled Materials ◽  
Assessment Techniques ◽  
Standardized Measurement ◽  
The Impact ◽  
Non Destructive

Recent progress in measurement techniques have given rise to increasing interest in non-destructive testing. Incorporating non-conventional, recycled materials in concrete (i.e. rubber crumbs from discarded tires), the heterogeneity is increased. Based on this, it is of importance to determine to what degree the accepted protocols, valid for traditional materials, are applicable to newly developed construction materials with particular interest to rubberized concrete. Several tests, including parameters missing from the standardized measurement techniques, such as the increasing rate of the frequency during the sweep for finding the resonant frequency of the specimen, were conducted on two types of concrete: traditional and rubberized concrete. The assessment of the dynamic properties was done by means of the forced vibration method and the impact method. The obtained results indicate the fact that current procedures should be applied with care when considering aggregate replacement in traditional concrete by other recycled materials.

Homogenization Procedure Effect on Microscopical Performance of Concrete Containing Supplementary Cementitious Materials

2020 ◽  
Vol 995 ◽  
pp. 168-173
Author(s):  
Zdeněk Prošek ◽  
Vladimír Hrbek ◽  
Petr Bílý ◽  
Lukáš Vráblík
Keyword(s):  
High Performance ◽  
Chemical Resistance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Macro Level ◽  
Homogenization Procedure ◽  
Homogenization Process ◽  
Concrete Mixtures ◽  
Major Factors

The advantages of supplementary cementitious materials (SCM) use in concrete, such as reduced cement consumption and overall material improvement (durability, chemical resistance, etc.), are widely known. Our research focuses on two major factors connected to high performance concrete (HPC) containing SCM, the content of selected SCM and the homogenization process used for concrete mixture. Both of these aspects of this research were addressed by the authors from macro-level of the material. In this contribution, the focus is directed on microscopical performance of concrete mixtures with highest macro-mechanical features with respect to both homogenization procedure and SCM containment.

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