An Experiment Investigation on Physical and Mechanical Properties of High Strength Concrete with Suitable Admixture

2019 ◽  
Vol 972 ◽  
pp. 10-15
Author(s):  
B.C. Gayana ◽  
Mallikarjuna Shashanka ◽  
Avinash N. Rao ◽  
Karra Ram Chandar

Concrete is an essential construction material. Even-though conventional concrete performs and satisfy the structures under normal conditions, a few special situations require very high compressive strength of concrete. An experimental investigation is done to develop high strength concrete with suitable admixtures and steel fibers. The properties of fresh and hardened concrete with alccofine as partial replacement for binder and poly-carboxylate ether (Glenium 8233) and steel fibers is investigated for the workability and mechanical properties i.e., compressive, splitting tensile and flexural strength of concrete. Based on the results, the strength increased with the addition of alccofine compared to the control mix. Hence, by optimum percentage of alccofine, high strength of concrete of 112 MPa can be obtained.

Very recently, the world of nano technology has initiated to fabricate new materials owing to the demand for their use in enhancing the properties of different materials in general and, materials used in the construction industry in particular. In this study, the results of an exhaustive experimental analysis, on the use of nano alumina with cement powder to enhance the grade and strength of concrete has been undertaken. The influence of the nano alumina in concrete with different proportions has been studied to assess mechanical properties of concrete with reference to normal concrete. The test results indicate that the use of nano alumina in concrete has enhanced the mechanical properties of hardened concrete. This nano alumina based high strength concrete (HSC) has an enhanced compressive strength of 64.17 N/mm2 (MPa) after 28 days, which is a significant improvement over normal concrete. All the mixes having nano alumina in different proportions gave better results as compared to normal conventional concrete mix. The Rebound Hammer, Ultrasonic Pulse Velocity, SEM and TEM analysis further validate the above findings.


Author(s):  
Afzal Basha Syed ◽  
Jayarami Reddy B ◽  
Sashidhar C

In present era, high-strength concrete is progressively utilized in modern concrete technology and particularly in the construction of elevated structures. This examination has been directed to explore the properties of high-strength concrete that was delivered by using stone powder (SP) as an option of extent on sand after being processed. The aim of the research is to study the effect of replacement of sand with stone powder and substitution of cement with mineral admixtures (GGBS & Zeolite) on the mechanical properties of high strength concrete. The test results showed clear improvement in compression and split tensile nature of concrete by using stone powder and mineral admixtures together in concrete. The increment in the magnitude of compressive strength and split tensile strength are comparable with conventional concrete.


2018 ◽  
Vol 199 ◽  
pp. 11006
Author(s):  
M. Iqbal Khan ◽  
Wasim Abbass

The hybridization of fibers for arresting the crack in concrete is a key factor and play an important role to improve mechanical properties of high performance concrete with respect to mono fibers. The effect of hybridization of hooked end steel fibers with different length and diameter on mechanical properties of high strength concrete was investigated in this research work. The different percentages of hook ended fibers (60 mm and 40 mm) are hybridized in the concrete mixture while keeping total percentage of fibers by volume equal to 1%. The compressive and flexural properties with complete load verses deflection curves of hybrid steel fiber reinforced high performance concrete were investigated to find the optimized dosage of hybrid steel fibers. The results showed that the hybridization of fiber provided better compressive and flexural performance. It was also observed from the results that combination of 65% of 60 mm and 35% of 40 mm hooked end fibers proved to be best for enhancement in compressive and flexural properties.


2018 ◽  
Vol 24 (2) ◽  
pp. 138-144 ◽  
Author(s):  
Tomasz DRZYMAŁA ◽  
Wioletta JACKIEWICZ-REK ◽  
Jerzy GAŁAJ ◽  
Ritoldas ŠUKYS

There has been a tendency to design ever slender building construction using high strength concrete in recent years. Application of HSC is also growing in tunnel construction. One of the most important challenges is to control explosive spalling of concrete and the method recommended by Eurocode 2 (EN 1992-1-2:2008/NA:2010P) is addition of polypropylene fibres to the mix. The purpose of the research described in this paper was to evaluate the changes of mechanical properties of HSC exposed to the effect of high temperature. The tests were carried out on three types of high strength concrete: air-entrained concrete, polypropylene fibre-reinforced concrete and reference concrete having constant water/cement ratio. The properties of hardened concrete including compressive strength, tensile splitting strength, flexural strength and E-modulus were studied. The latter tests were carried out on both on concrete cured at 20 °C and concrete subjected to high-temperature conditions at 300 °C, 450 °C and 600 °C. The results enabled us to evaluate the effect of high-temperature conditions on the properties of high-performance concrete and compare the effectiveness of the two methods designed to improve the high-temperature performance of the concrete: addition of polypropylene fibres and entrainment of air.


Author(s):  
Mohammed Abed ◽  
Rita Nemes

The sustainability of engineering products has become a basic requirement instead of a mere choice because the harmony between economic activity and the earth’s ecosystem must be seriously considered. The influence of using three unprocessed waste powder materials as cement replacing materials (CRMs) and/or coarse recycled concrete aggregate (RCA) as a partial replacement of coarse natural aggregate (NA) on fresh and mechanical properties of self-compacting high-strength concrete (SCHSC) is investigated in this study. The activation index of the CRMs on the cement paste is tested as an initial step. The CRMs, namely, waste fly ash (WFA), waste perlite powder (WPP) and waste cellular concrete (WCC), are tested through 21 mixtures allocated by seven different series with three mixes of each. The mechanical properties of the 21 concrete mixes are determined after one, three and nine months of curing. Results of compressive strength, splitting tensile strength, flexural strength and modulus of elasticity are presented. This work shows that the mechanical and environmental performance of SCHSC can be improved by the replacement of NA by RCA of up to 50% and the replacement of cement by WPP or WFA of up to 15%. Using WCC is not recommended to be reached 15% and using WFA is preferable to be with incorporating RCA rather than NA alone. Findings indicate that incorporating waste materials can be valuable in SCHSC, thereby potentially leading to an increasingly green environment and paving the way for advancements in sustainable construction.


Sign in / Sign up

Export Citation Format

Share Document