bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Different Admixtures on the Strength of Sulphur Concrete
Authors: Czarnecki B , Gillott JE 
Published: January 2010

Abstract
The strength of sulphur concrete is affected by factors such as type of aggregate, aggregate particle shape and texture, amount of sulphur binder in the mix, and type of admixture used. The density of this concrete is also affected by these factors. Some of these concretes perform poorly in moist conditions, as shown by loss of more than 30% strength. Increased amounts of sulphur binder adversely affect the strength of concrete; however, loss of strength of such mixes upon immersion in water is smaller. Type of aggregate influences the strength of concrete, but no correlation was found between the petrography and mineralogy of aggregates and the strength of concrete; the strongest aggregate did not always produce the strongest concrete.
Four types of admixtures were employed: glycerin, crude oil, and two types of silanes. Glycerin and crude oil generally decreased the strength of sulphur concrete. Silane admixtures act as adhesion promoters and are capable of rendering the concrete hydrophobic. Concretes made with aggregates that were pretreated with silanes generally showed a dramatic increase in strength under both dry and wet conditions.
Drying Shrinkage of Glass Fiber Reinforced Concrete
Authors: Al-Obaid YF 
Published: January 2010

Abstract
Experimental tests have been carried out on the shrinkage behavior of glass fiber reinforced concrete. Reinforcing concrete by mixing in fiber is one method for preventing cracks occurring due to drying shrinkage. The tests performed show that shrinkage strain is decreased with the increase of the fiber content. A three-dimensional finite-element analysis was carried out on samples tested in the laboratory. The analytical results produced show good agreement with those obtained from the experimental results.
Observations of Healing of Cracks in High-Strength Lightweight Concrete
Authors: Mor A , Monteiro PJM , Hester WT 
Published: January 2010

Abstract
Some favorable properties of lightweight aggregate concrete are shown to originate from its internal structure, which combines relatively flexible aggregate with more rigid cement paste matrix. Scanning electron microscopy (SEM) was used to analyze the cracking pattern which developed under cyclic loading. The cracks appear to originate in the hard brittle matrix and progress into the aggregate. At low load levels, some cracks seem to deflect and lose energy as they penetrate the aggregates, with many never emerging from the other side or emerging as thinner cracks.
A process of healing of cracks through the formation of new products appears to restore integrity and enhance strength of a previously cracked concrete which was allowed to rest for a long period after cracking. Micrographs of the healed cracks are presented.
Effect of Coarse Aggregate on the Behavior of Normal and High-Strength Concretes
Authors: Ezeldin AS , Aitcin P-C 
Published: January 2010

Abstract
The effect of four coarse aggregate types on the compressive strength, flexural strength, and flexural strength/compressive strength ratio of normal- and high-strength concrete are reported. With normal-strength concrete mixtures, it was found that the coarse aggregate type did not greatly influence the mechanical properties. However, the high-strength concrete mixtures containing the limestone aggregate produced higher compressive strength than the concrete mixtures containing either gravel or granite aggregates. The flexural behavior of high-strength concrete was not affected by the aggregate type. Also, the experimental results did not show a conclusive influence of the aggregate type on the variation of flexural strength/compressive strength ratio.
Crushed Tile Coarse Aggregate Concrete
Authors: Khaloo AR 
Published: January 2010

Abstract
This paper investigates the potential of crushed tiles as coarse aggregate in concrete. Test results of bulk, saturated surface dry (SSD) and apparent specific gravities, bulk unit weight, water absorption, resistance to abrasion, percent of voids and grading (performed as per ASTM standards) on two types of crushed tiles were compared with the results of conventional crushed stone aggregate. Also included are results from tests on concrete cylinders under uniaxial compression, split tension, and beams under flexure to determine the influence of variables of test age on concrete strength, type of tiles, and ratio of volume of crushed tile to the total volume of coarse aggregate in concrete. Recommendations for use of crushed tile as coarse aggregates in concrete are given.
A Latex-Modified Concrete Overlay on Plain-Jointed Concrete Pavement
Authors: Glauz DL 
Published: January 2010

Abstract
A latex-modified concrete overlay was placed on Interstate 5 in Northern California at a Strategic Highway Research Program SPS-6 test site. The objective of the test was to evaluate a potentially lower cost latex overlay system. The cost of the overlay would be reduced by eliminating surface prewetting and the wet burlap cure. The test section was placed 300-m long across three lanes. Unusual features of the overlay were: (1) it was placed on a dry substrate, (2) latex content was 43% higher than conventional practice, (3) cure was by curing compound rather than wet burlap, and (4) it was on a plain jointed portland cement concrete pavement. Bond to the substrate was very good. Curing compound provided an adequate curing membrane when applied at the proper rate. The system was evaluated annually. To date, the only problem has been at the joints, which present a serious problem for a bonded overlay. Delaminations or spalls have occurred at most of the transverse joints. The objective was met although the system is not suitable for use on jointed pavements.
A latex-modified concrete overlay can be placed on a dry substrate and bond well. It can also be cured successfully with a curing compound that conforms to Specification for Liquid Membrane-Forming Compounds for Curing Concrete (ASTM C 309), Type 2, Class B. This type of overlay is not suitable for a jointed pavement without careful attention to the joint detail.
Precision of Tests for Assessment of the Deicer Salt Scaling Resistance of Concrete
Authors: Marchand J , Pleau R , Pigeon M 
Published: January 2010

Abstract
Some aspects of the variability of Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals (ASTM C 672) measurements are discussed in this paper. The influence of the operator's subjectivity on the visual rating is studied. The relationship between the visual rating and the cumulated mass of scaled-off particles is also analyzed. From a statistical analysis of several hundred different concrete mixtures, the variability of the test method is estimated for various types of concrete considering only the cumulated mass of scaled-off particles. Using the same statistical analysis, the precision of ASTM C 672 is finally compared to that of the Canadian brine immersion test (Precast Concrete Paving Blocks, CAN/CSA A231.2 M85) designed to assess the deicer salt scaling resistance of precast concrete elements.
Durability of Reinforced Lightweight Mortars with Corrosion Inhibitors
Authors: Batis G , Kouloumbi N , Katsiamboulas A 
Published: January 2010

Abstract
The aim of this experimental work is the examination of the performance of reinforced mortar specimens containing Greek fine-pumice aggregates together with corrosion inhibitors (sodium nitrite or sodium benzoate or iron oxides) added in order to lower the corrosion rate of steel reinforcement in a chloride environment. The durability of the specimen was evaluated by measuring the corrosion potential and the mass loss time dependence of the steel rebar, the carbonation depth, the porosity, and the compressive strength of the specimens. Correlation of the above results revealed that the corrosion inhibitors examined have a protective effect on the steel, while the changes of the mechanical strength of the relative lightweight mortars are not significant compared to the practical needs. The most efficient inhibitor was sodium nitrite in both concentrations examined, that is, 2 and 5%.
High-Strength Concrete: An Annotated Bibliography 1930–1979
Authors: Carrasquillo RL , Nilson AH , Slate FO 
Published: January 2010

Abstract
The purpose of this bibliography is to present a guide to the existing literature on high-strength concrete. This bibliography covers most of the relevant writings of this subject in the English language and some writings in other languages. High-strength concretes are here defined as concretes with strengths considerably higher than usually obtained by a given production process. There is general agreement on the need for a unified effort for the development of knowledge of this new material so that it may be used with confidence in design and construction.
The Action and Application of Two New ASTM Specifications for Shrinkage-Compensating Cement in Concrete: ASTM C 845 and C 878
Authors: Gulyas RJ , Garrett MF 
Published: January 2010

Abstract
The past theory of the action of shrinkage-compensating cements is discussed and recent findings that refute the internal compressive stress concept are presented in favor of the American Concrete Institute (ACI) Committee 223 net positive elastic strain behavior (spring action theory) for the proper functioning of concrete with shrinkage-compensating expansive cement.
A method of using less than the minimum ACI-223 committee recommendation of 0.15% steel is presented based on two past research studies.
Examples of typical installations are shown along with some interesting concepts that deal with curvature control (curling/warping) as a result of reversed differential shrinkage/expansion strains. A case for using less than the minimum ACI-318 recommendation of 0.188% steel is also presented for this type of concrete in structural reinforced concrete. The proper type of expansion/isolation joints are presented that exclude current ASTM materials.
This paper provides the design engineer with a summary of the current research and thinking for design concepts for the use of this material that is fundamentally different than conventional concrete. It also describes the working relationship of ASTM Specification for Expansive Hydraulic Cement (C 845) and ASTM Test for Restrained Expansion of Shrinkage-Compensating Concrete (C 878), respectively, covering shrinkage-compensating expansive cement and its concrete prism for measuring expansion strains.
An Experimental Technique for Obtaining Complete Stress-Strain Curves for High Strength Concrete
Authors: Shah SP , Gokoz U , Ansari F 
Published: January 2010

Abstract
For a rational design of concrete structures, it is necessary to know both the ascending and the descending parts of the stress-strain curve of concrete subjected to uniaxial compression. It is difficult to determine the descending part experimentally because of the interaction between the testing system and the specimen, especially for concrete of high compressive strength. The influence of the testing machine depends on the stiffness of the machine, the frequency response of the system, the length and diameter of the specimen, the strength of concrete, the rate of loading, and the inherent brittleness of the material. For a closed-loop testing machine, the specimen-machine interaction also depends on the parameter chosen to control the loading. It is shown that the descending part of the curve can be obtained by controlling the circumferential strain even when the axial strain control produces an unstable failure. A method of testing specimens at a controlled rate of circumferential strain increase is described. Stress-strain curves of concrete subjected to uniaxial compression using both the axial and the lateral strain as a control were compared for compressive strengths ranging between 70 to 90 MPa (10 000 to 13 000 psi).
Proportioning of Coarse Aggregate for Conventionally and Gap-Graded Concrete
Authors: Ehrenburg DO 
Published: January 2010

Abstract
This paper presents a set of tables for proportioning 38-mm (1.5-in.) maximum size conventionally or gap-graded concrete. The tables were compiled on the basis of Weymouth's concept of particle interference, considerations of minimum surface area, and certain other considerations. It will be noted that the recommended gradations of the coarse aggregate often lie somewhere between conventional and gap-graded patterns. Laboratory tests have established the validity of the proposed method. The procedure is laboratory oriented in that the matrix requirement is established on the basis of trial mixes. The meshing of test results with data obtained from the proposed tables is illustrated by a practical example.
Evaluation for Durability and Strength Development of a Ground Granulated Blast Furnace Slag
Authors: Hogan FJ , Meusel JW 
Published: January 2010

Abstract
This paper covers the evaluation of a ground granulated blast furnace slag as a partial replacement for portland cement in mortars and concrete. The ground slag was evaluated for strength-producing properties as well as durability performance when used to replace 40 to 65% portland cement. This study shows that the ground slag when used to replace 40 to 65% portland cement did significantly improve strengths, sulfate resistance, and alkali aggregate reactivity.
Influence of Pozzolanic, Slag, and Chemical Admixtures on Pore Size Distribution and Permeability of Hardened Cement Pastes
Authors: Manmohan D , Mehta PK 
Published: January 2010

Abstract
Durability of concrete is greatly influenced by the permeability of the cement paste which in turn is governed by the pore size distribution. Some mineral and chemical admixtures are known to enhance the durability of portland cement concrete. The objective of this work was to investigate how the pore size distribution and permeability of portland cement pastes are modified by the addition of pozzolanic admixtures, blast furnace slag, and chloride salts. The effectiveness of pozzolans in reducing the volume of large pores and permeability was found to depend on the reactivity of the pozzolan used. Large additions of granulated blast furnace slag increased the total pore volume, however the pore size distribution was shifted toward finer pores and therefore the permeability of the paste was reduced. Among the chloride admixtures, namely calcium, magnesium, and sodium chloride, magnesium chloride was most effective in reducing both the volume of large pores and permeability of the cement pastes.
Flexural Fatigue of Polymer Concrete
Authors: Woelfl GA , McNerney M , Chang CJ 
Published: January 2010

Abstract
This paper describes modulus of rupture and flexural fatigue testing performed on beam specimens made of Silikal® polymer concrete and course aggregate. Test results indicate that modulus of rupture of polymer concrete increases with increasing rate of loading similar to portland cement concrete. Fatigue test results show good correlation with a mathematical expression relating probability of survival with stress level and number of cycles to failure. This equation was developed and used by other investigators for portland cement concrete. Test results indicate that frequency of loading influences the fatigue life of polymer concrete, but a short rest period within each loading cycle probably does not. Further fatigue study is recommended in the paper.
Production of Artificial Porous Aggregates from Fuel-Containing Industrial Wastes in the USSR
Authors: Ivanenko GP , Vasilkov SG 
Published: January 2010

Abstract
Data on the use in the USSR of fuel-containing industrial wastes in the production of artificial porous aggregates for lightweight concrete are presented. The main peculiarities of the production technology of artificial porous aggregates from thermal power plant ashes, by-products of mining, and concentration of coal are presented. Formation processes of the porous structure's of aggregates during production by agglomeration method is discussed. Data on properties of porous aggregates and lightweight concrete are presented.
Variability and Control of Class C Fly Ash
Authors: McKerall WC , Ledbetter WB 
Published: January 2010

Abstract
Five Class C fly ashes produced in Texas were analyzed for their potential usefulness as a construction material in highways. In order to determine the variability a new test method was devised and termed the calcium oxide heat evolution test, whereby the total calcium oxide content of the Class C fly ashes can be quickly and reliably determined in the field, as a quality control test. By using this test plus the traditional physical and chemical characterizations, the variability of typical fly ashes produced in Texas was ascertained. They were shown to generally conform to the requirements of ASTM for Class C fly ash. In addition to the analysis the potential usefulness of this type of fly ash is discussed, and the test procedures for calcium oxide content are described.
Chloride Penetration and the Deterioration of Concrete Bridge Decks
Authors: Cady PD , Weyers RE 
Published: January 2010

Abstract
The rapid deterioration of the nation's bridges is a widely recognized problem. A major contributor to this problem is bridge deck deterioration caused by chloride-induced corrosion of reinforcement. Chlorides are derived primarily from the application of roadway deicing salts. This paper synthesizes empirical data from previous studies with the diffusion theory in developing a predictive model for chloride infusion of bridge decks. The model includes the effects of subsidence cracking over the reinforcement. Primary input data consist only of average reinforcement cover, which is easily obtainable with existing instrumentation. The model is intended to serve as a useful, rational means of providing information for life-cycle costing in bridge deck rehabilitation planning studies.
A Method for Analyzing Void Distribution in Air-Entrained Concrete
Authors: Philleo RE 
Published: January 2010

Abstract
A method is derived that makes possible the determination of the fraction of hardened cement paste within any stipulated distance of the nearest air void as a means of determining the extent to which the paste is protected from the damaging effects of freezing. The required input consists of the total air content and the number of air voids per unit volume. Both can be determined from a Rosiwal linear traverse performed by microscope on a polished section of concrete. Determining the void density requires a count of chord intercepts in two or three small size groups.
Principles Underlying Production of High-Performance Concrete
Authors: Mehta PK , Aïtcin P-CC 
Published: January 2010

Abstract
Durability rather than high strength appears to be the principal characteristic for high-performance concrete mixtures being developed for use in hostile environments such as seafloor tunnels, offshore and coastal marine structures, and confinement for solid and liquid wastes containing hazardous materials. Strength, dimensional stability, impermeability, and high workability are usually the principal characteristics required of high-performance concrete.
In this paper an overview of the composition of concrete and its effect on the properties desired for high performance is given. This overview can be used as a basis for selection of component materials and mix proportioning. A new step-by-step procedure for mix proportioning is described. The calculated mix proportions from this procedure appear to be consistent with the state-of-the-art laboratory and field practice. Also, a brief review is given of concrete production and construction practices essential for making a high-performance end product.
The Influence of Size and Hardness of Sand Particles and Their Proportions on the Friction Characteristics of Cement Mortars: A Laboratory Study
Authors: Kolias S 
Published: January 2010

Abstract
Laboratory friction tests on cement mortar specimens, prepared with various fractions of limestone and emery sand, were carried out using the accelerated polishing machine and the British pendulum tester. Two types of investigations were performed. The first consisted of mixes with constant grading of sand, either limestone or emery, in which one fraction was replaced by the same fraction of the other type of sand. The second consisted of mixes of limestone sand in which a certain amount of emery sand, each one of four different fractions, was added each time. The exact amount of emery sand added was calculated for each fraction so that in each series of tests the total surface area of emery sand was constant, regardless of the fraction used.
It was found that the finer fractions are more effective in influencing the skid resistance value (SRV) of mortars. The max increase in SRV (29.7%) is achieved when the 0.297/0.149 fraction of limestone sand is replaced by the same fraction of emery sand; therefore, an SRV value of approximately 90% of the SRV of mortar, containing entirely emery sand, is obtained. The second investigation confirmed that the total surface area of hard particles determines the friction characteristics of the mortars. It seems, however, that an optimum total surface of hard particles exists, and further increase of which does not cause additional increase of the SRV.
The Use of the Flow Length Concept to Assess the Efficiency of Air Entrainment with Regards to Frost Durability: Part I—Description of the Test Method
Authors: Pleau R , Pigeon M 
Published: January 2010

Abstract
This paper describes a numerical method to determine the flow length and other characteristics of the air-void system in hardened concrete. Physically, the flow length represents the distance that freezable water must travel through the cement paste to reach the perimeter of the nearest air void. It is expected to be a better indicator of the frost durability of concrete than the commonly used Recommended Practice for the Microscopial Determination of Air Void Content and Parameters of the Air Void System in Hardened Concrete (ASTM C 457) spacing factor. The flow length is obtained from the microscopical examination of polished concrete sections. It can be determined by recording the size-distribution of the circles intercepted by the plane on a given surface area or by recording the size-distribution of the chords intercepted along a given line of traverse. A numerical example is given to illustrate the advantages of the proposed method. The flow length is very similar to the Philleo factor, but it provides a more accurate estimation of the real distribution of air voids through the cement paste.
Do We Need a Standard Concrete Fracture Mechanics Test?
Authors: Struble LJ , Lange D 
Published: January 2010

Abstract
Fracture mechanics has allowed scientists and engineers to understand brittle fracture and to determine the conditions that cause a crack to grow in an brittle manner and lead to failure of the structure. In this paper we consider the information that fracture mechanics provides, especially that which is not obtained from a simple test of strength. Fracture mechanics provides a measure of toughness, the extent to which a material can undergo deformation without fracturing. For a linear elastic material, the measurement and interpretation of fracture toughness is fairly straightforward. Concrete is not such a material; it is rather described as quasi-brittle, and only recently has research led to the development of fracture mechanics tests suitable for such quasi-brittle materials. We show in this paper that fracture toughness provides considerable information about concrete over and above what we can learn from strength. We also show how the practicing engineer can benefit from the use of fracture criteria in design. However, fracture specifications will not be developed until there is a standard test method. Researchers have now developed tests that are suitable as standards. Therefore, we conclude that a need exists for a standard test and that it is time to begin its consideration.