slag concrete time of set

Frontiers | The Effect of Blast Furnace Slag/Fly Ash Ratio ...

Feb 14, 2019· The aim of this study was to determine the effects of partial fly ash substitution in to a series of alkali-activated concrete based on a high-MgO blast furnace slag BFS. Mixes were activated with various amounts of sodium silicate at alkali modulus (mass ratio SiO2/Na2O) values of 1.0, 0.5, and 0.25. The results showed that, an increase in the fly ash content extended the initial setting time ...

Concrete Set Time - Slag Cement Association

Time of Set. Time of initial set is influenced by the use of slag cement and fly ash. Concrete made with slag cement can have faster set times than concrete made with fly ash (Figure 2). Pumpability and Finishability. Pumpability with slag cement and fly ash is generally improved largely due to the addition of fines to the matrix.

SCMs in Concrete: Slag Cement - National Precast Concrete ...

May 05, 2017· Since pozzolans extend the hydration process, concrete made with slag cement can exhibit a lower heat of hydration, slower set times and lower early age strength. However, at 28 days the strength results displayed by slag cement concrete can exceed those of ordinary portland cement concrete.

"Sulfate Optimization in the Cement-Slag Blended System ...

Jul 15, 2021· Optimization of sulfur trioxide (SO3) content is typically conducted for plain cements (OPC-based) paste or mortar systems using compressive strength testing and isothermal calorimetry for quality control. The objective of these procedures is to ensure adequate strength and set properties by controlling the time of occurrence of the aluminate peak by adjusting the SO3 content by incremental ...

Evaluation of Portland Cement Concrete Pavement With High ...

slag cement, one with 35 percent slag cement, and two with conventional Type I/II cement without slag. The later two mix designs were 24 hour and 48 hour mixes, indicating that they were for special situations that required quicker set times. The components for each mix design are summarized in Tables 1-5 and provided in greater detail in ...

Determining the slag fraction, water/binder ratio and ...

Feb 01, 2014· 1. Introduction. Ground-granulated blastfurnace slag (GGBS) is increasingly being used in concrete due to its many benefits. For example, partial replacement of Portland cement with slag is commonly specified for structures exposed to sea-water because slag greatly enhances the resistance of concrete to chloride ingress and therefore delays the time until embedded reinforcement starts to …

Slag Cement Information Sheet Index

The Slag Cement Association has published 28 information sheets in the Slag cement in Concrete series. These are listed below in numeric order. Click on the icon to the left of the title of any of the sheets for a free download. Also, the sheets are arranged and summarized by topic on the " About Slag Cement " choice in the navigation bar. Number.

Slag set time in cold weather - Structural engineering ...

Dec 13, 2007· RE: Slag set time in cold weather. concretemasonry (Structural) 13 Dec 07 15:50. No question about the retarding effects or slow strength gain when you are using fly ash and slag. The cool weather temperatures magnify the effects, no matter what the concrete temperature at placement. Even though you may get a 28 day cylinder strengths specified ...

Table 1 Setting Time of Concrete at Various Temperature

Use of Admixture and Its Effects on Setting Time. Initial set, as defined by ACI 116R, is a degree of stiffening of a mixture of cement less than final set, generally stated as an empirical value indicating the time in hours and minutes required for the cement paste to stiffen sufficiently to resist to an established degree, the penetration of a weighted test needle.

Ground Granulated Blast Furnace Slag

The time of set is slightly delayed by approximately 20 minutes, and early compressive strengths are decreased. GGBFS also causes increased drying shrinkage. When using this or any other alternative cementing material with portland cement, it is necessary to create trial mixtures to ensure proper proportioning for the desired properties.

Concrete Admixtures for Hot Weather - The Concrete Network

In hot weather, concrete with fly ash or slag will set a bit slower. But using admixtures to control set and slump is more common and does not lower the quality of the concrete or change its color. In the July 2002 issue of Concrete Construction ("Stamping Concrete: Managing Initial Set Times"), Joe Nasvik wrote the definitive guide, advocating ...

(PDF) Setting Times of Fly Ash and Slag-Cement Concretes ...

At high temperatures, slag concrete has shorter setting times than Type I cement concrete. Relationships are presented for setting time as a function of penetration resistance, temperature, and ...

Solved: What Effect Does Blast Furnace Slag Have On Set Ti ...

Question: What Effect Does Blast Furnace Slag Have On Set Time Of Concrete, And What Effect Does It Have On The Permeability Of Concrete? (1 Mark) 7. This problem has been solved! See the answer. Show transcribed image text. Expert Answer (1 rating) 1. Setting time is incresed when blast furnace slag is used.

Types of Admixtures of Concrete & Cement | Chemical, Mineral

Mar 18, 2017· A material other than water, aggregates, or cement that is used as an ingredient of concrete or mortar to control setting and early hardening, workability, or to provide additional cementing properties. Admixtures of concrete are generally used to alter the properties of concrete (such as increased workability or reduced water content, acceleration or retardation of setting time, …

Evaluation of Ground Granulated Iron Blast-Furnace Slag ...

set are common for GGBFS concrete mixes. This is of particular concern to LA DOTD. In paving concrete, joints shall be completed in a timely manner, generally within 10 hours. The time management of the joint sawing operation could be tricky if the set is delayed or if the time window is narrowed. This is the time in between

Slag Cement: The Other SCM

Apr 08, 2019· Slag cement, previously known as ground-granulated blast-furnace slag ⠀䜀䜀䈀䘀, has been used in concrete for well over 100 yeൡrs ⠀䄀䌀䤀 ㈀ ㄀㄀. The first recorded production in the US of blended cement containing both slag and portland cement was in 1896 ⠀䄀䌀䤀 ㈀ ㄀㄀. ... Time of Set ...

Effect of blast furnace slag powder on compressive ...

slag is a long one. Production of Portland blast-furnace slag cement began in 1910, and the Japanese national standard for Portland blast-furnace slag cement (JES 29) was formulated in 1926.some of the study has been done in past which summa-rized as: 1. Sun, …

Slag Cement Production

SCIC #3, Concrete Time of Set, examines conditions that affect set times, including the incorporation of slag cement. Graphs compare the effect of temperature and accelerators on initial time of set in mixtures with portland cement, 30% slag cement and 50% slag cement.

Effect of steel slag on the hydration and strength ...

Dec 30, 2020· In this study, effects of steel slag on the hydration and strength development of calcium sulfoaluminate (CSA) cement were investigated. Pastes with 0%, 10%, 20%, and 40% (by mass) of steel slag replacements for CSA cement were tested for setting time, chemical shrinkage, electrical resistivity, and compressive strength.

Slag Cement Questions

Slag cement will tend to increase time of initial set, which is often a benefit in warm weather. In cooler weather, accelerators, heated materials or lowering the percentage of slag cement in a mixture (as a portion of cementitious material) can be employed to decrease times of set (see SCIC #3).

Factors Affecting the Setting Time and Compressive ...

Wollastonite/slag mass ratios as well as the total amount mixed in the setting time and compressive strength of the paste. The setting time was measured using a Vicat needle immediately after mixing while the compressive strength was taken 7 days after curing. An optimal formulation has been

Modeling the corrosion initiation time of slag concrete ...

Modeling the corrosion initiation time of slag concrete using the artificial neural network O.A. Hodhod a, H.I. Ahmed b,* a Professor of Properties and Strength of Materials, Struct. Eng. Dept., Faculty of Engineering, Cairo University, Egypt

How to Make Cement From Blast-Furnace Slag

Apr 23, 2017· Time, of set—initial, 18 to 20 minutes; final, 35 to 45 minutes. This is a very quick-setting cement when compared to the ordinary slag cement. ... It was not that the engineer worried about the seven days set, but that he wanted a 28 days set. With regard to slag cement, he would like to ask Mr. Poole to add a word as to the possible amount ...

Initial Setting Time - an overview | ScienceDirect Topics

Initial and final setting times of cement, which are determined using the Vicat needle test, are used as a quality control measure for cement characterisation (EN-196, 1995) and specified as a requirement in related standards (EN-197, 2011; ASTM C150, 2015).A comparison between the initial and the final setting time of cements manufactured with and without CS (Alp et al., 2008; Supekar, 2007 ...

Effects of Ground Granulated Blast Furnace Slag in ...

2001 by slag cement manufacturers and the Slag Cement Association, the American Concrete Institute officially reviewed and changed the terminology from GGBFS to slag cement (ACI Committee 233, 2004). The term slag cement will be used throughout this paper when referring to finely-ground granulated blast-furnace slag.

Steel Slag - an overview | ScienceDirect Topics

The incorporation of air-quenching steel slag of 0.315–5 mm (in which the content of Fe 1-σ O is over 30%) into concrete to fabricate mechanically sensitive concrete was investigated by Li et al. in 2005 [21]; subsequently, Jia performed a systematic study of this concrete (as shown in Figure 2.14) [23,50].

Why use Fly Ash and Slag in Concrete? - Bay-Lynx ...

Although set times are prolonged with fly ash, in just 28 days, the strength of the concrete will surpass the same mix without the fly ash. Slag is similar to fly ash in that it is finer than standard Portland cement and is also cheaper as it is a process byproduct.

Setting Time of Cement Concrete - Stages and Processes ...

Final Setting Time is defined as the period elapsing between the time when water is added to cement and the time at which the needle of 1 mm square section with 5 mm diameter attachment makes an impression on the test block . 600 minutes is the maximum time specified for the final set for all the above mentioned Portland cements.