Fires are always known for seriously deteriorating concrete in structures, especially for those with certain carbonation due to long-time service. In this paper, 75 prism specimens were prepared and divided into four groups (three carbonated groups and one uncarbonated group). Specimens were tested under different temperatures (20, 300, 400, 500, 600, and 700°C), exposure times (3, 4, and ...

This paper investigates the combined effects of temperature and time on the performance of polycarboxylate-, melamine sulfonate- and naphthalene sulfonate-based high-range water-reducing admixtures used to enhance the flow of cement paste.

Cemented paste backfill (CPB) is an economic and environmental friendly technique applied in underground mining for supporting surrounding rock and replacing the pillar. However, little is known about the temperature effects on CPB in mines having a large temperature fluctuation. The main purpose of this research was to investigate the effect of temperature change on the rheological properties ...

Nov 20, 2020· 1. Introduction. The failure of cement-based composites is a grading and multi-scale process: the pre-existing micro- cracks develop to macro- ones, which threatens the mechanical properties and durability of concrete,,, .In order to restrict the cracks in different grades and scales, hybrid fibers with different sizes and mechanical properties are used in cement-based materials.

The objective of this limited study was to provide an overview of the effects of elevated temperature on the behavior of concrete materials and structures. In meeting this objective the effects of elevated temperatures on the properties of ordinary Portland cement concrete constituent materials and concretes are summarized.

Effect of temperature on the pozzolanic properties of Metakaolin ... Effect of temperature on the pozzolanic properties ... obstacle in reducing cement content specially in mass concrete .... grinding mill for a time of one an hour. Read more

Jun 06, 2011· This paper presents the effect of temperature on the thermal properties of different types of high-strength concrete (HSC). Specific heat, thermal conductivity, and thermal expansion are measured for three concrete types, namely, HSC, self-consolidating concrete (SCC), and fly ash concrete (FAC), in the temperature range from 20–800°C.

May 02, 2019· At each working time point and temperature, cement A showed significantly more intrusion than cement B (p = 0.044 - < 0.001). There was no effect of temperature on intrusion depth regardless of working time to implantation for either cement with the exception of cement B when comparing 60 versus 70°F at 0% working time (p = 0.004).

This paper investigates the effect of curing temperature on the hydration, microstructure, compressive strength, and transport of cement pastes modified with TiO 2 nanoparticles. These characteristics of cement pastes were studied using non-evaporable water content measurement, X-ray diffraction (XRD), compressive strength test, electrical resistivity and porosity measurements, and scanning ...

This paper investigates the effect of curing temperature on the hydration, microstructure, compressive strength, and transport of cement pastes modified with TiO 2 nanoparticles. These characteristics of cement pastes were studied using non-evaporable water content measurement, X-ray diffraction (XRD), compressive strength test, electrical resistivity and porosity measurements, and scanning ...

Effect of Elevated Temperature on Mechanical Properties of Limestone, Quartzite and Granite Concrete Muhammad Tufail1), Khan Shahzada1), Bora Gencturk2),*, and g Wei2) (Received April 3, 2016, Accepted October 11, 2016, Published online December 27, 2016)

An increase in the concrete mixing temperature from 18 to 35 degree C (65 to 95 degree F) required an average increase of 4.7 kg/cubic m (8 lb/cubic yd) of cement to maintain the strength level. An increase in the delivery time from 20 to 90 min required an additional 13.6 kg/cubic m (23 lb/cubic yd) of cement…

In this work, 0-3 lead zirconate titanate (PZT) was mixed with normal Portland cement to produce 0-3 connectivity composites. The effect of temperature on the dielectric properties such as the ...

This paper investigates the effect of curing temperature on the hydration, microstructure, compressive strength, and transport of cement pastes modified with TiO 2 nanoparticles. These characteristics of cement pastes were studied using non-evaporable water content measurement, X-ray diffraction (XRD), compressive strength test, electrical resistivity and porosity measurements, and scanning ...

The construction industry continues to develop and the requirements for cement performance are getting higher and higher. At the same time, in the steel industry, the discharge of steel slag is also increasing. The effective reuse of steel slag has become a prominent problem in the steel industry. . Therefore, it is envisaged to use steel slag as a raw material for the cement production ...

Cemented paste backfill (CPB) is an economic and environmental friendly technique applied in underground mining for supporting surrounding rock and replacing the pillar. However, little is known about the temperature effects on CPB in mines having a large temperature fluctuation. The main purpose of this research was to investigate the effect of temperature change on the rheological properties ...

This paper investigates the effect of curing temperature on the hydration, microstructure, compressive strength, and transport of cement pastes modified with TiO₂ nanoparticles. These characteristics of cement pastes were studied using non-evaporable water content measurement, X-ray diffraction (XRD …

Jun 06, 2011· This paper presents the effect of temperature on the thermal properties of different types of high-strength concrete (HSC). Specific heat, thermal conductivity, and thermal expansion are measured for three concrete types, namely, HSC, self-consolidating concrete (SCC), and fly ash concrete (FAC), in the temperature range from 20–800°C.

The importance of controlling concrete temperature is well understood. Temperature affects fresh and hardened properties of concrete as well as the thermal cracking potential. Careful attention must be paid to batch temperatures in hot and cold weather concreting. However, as evidenced by the graph below, the relative effect of hot cement on ...

Figure 3. Effect of SP and SSP on temperature development of a mortar mix Figure 4. Examples of cement heat release or 'fingerprints' of three different deliveries of the same cement. 0 6 12 18 24 30 10 20 30 40 50 60 70 Air Plain SP SSP Temperature [ o C ] Time from water addition [ h ]

The heat of hydration is affected most by C 3 S and C 3 A present in cement, and also by water-cement ratio, fineness and curing temperature. The heat of hydration of Portland cement is calculated by determining the difference between the dry and the partially hydrated cement (obtained by comparing these at 7th and 28th days).

Jun 06, 2011· This paper presents the effect of temperature on the thermal properties of different types of high-strength concrete (HSC). Specific heat, thermal conductivity, and thermal expansion are measured for three concrete types, namely, HSC, self-consolidating concrete (SCC), and fly ash concrete (FAC), in the temperature range from 20–800°C.

Abstract— An experimental investigation was conducted to evaluate the influence of elevated temperature s on the mechanical properties, phase composition and microstructure of silica flour concrete. The blended cement used in this investigation consists of ordinary Portland cement (OPC) and silica flour. The OPC were partially replaced by 0, 5, 10, 15 and 20% of silica flour.

Mar 15, 2012· Hui et al. have worked on cement mortars with nano-SiO 2 or nano-Fe 2 O 3 to explore their super mechanical potentials . In another work, Senff et al. have studied the effect of nanosilica on the rheology and fresh properties of cement pastes and mortars . In their work, rheological tests showed that after 75 min of starting the mixing, the ...

concrete and it is introduced in 1979 by davidovits to reduce the use of OPC in concrete. The objective of this project is to study the strength properties of class F fly ash (FA-50%) and ground granulated blast furnace slag (GGBS-50%) based geopolymer concrete (GPC) using mill …

Nov 20, 2020· 1. Introduction. The failure of cement-based composites is a grading and multi-scale process: the pre-existing micro- cracks develop to macro- ones, which threatens the mechanical properties and durability of concrete,,, .In order to restrict the cracks in different grades and scales, hybrid fibers with different sizes and mechanical properties are used in cement-based materials.