Physical-radiation shielding properties of concrete contains colemanite and ulexite

2020 ◽  
pp. 1420326X2096797
Author(s):  
Nazım Uçar ◽  
Adnan Çalık ◽  
Muhammet Emre ◽  
Iskender Akkurt

Radiation is an important phenomenon as it is used in a variety of different fields. However, its possible hazardous effect should be taken into account and it should be shielded. As the concrete is a widely used construction material, the mechanical and radiation shielding properties of concretes containing boron-bearing aggregate additives have been studied. The results show that the addition of colemanite or ulexite into concrete has significant effects on density, workability, compressive and flexural strength, elastic modulus and radiation shielding. The results also show that concrete containing colemanite or ulexite is no more effective in the attenuation of gamma rays than ordinary concrete.

2020 ◽  
Vol 34 (07) ◽  
pp. 2050046
Author(s):  
Jinghui Fan ◽  
Juying Wu ◽  
Yan Ma

Ethylene Propylene Diene Monomer (EPDM) composites filled with 0–400 phr [Formula: see text] (PWO) were prepared by conventional process using a two-roll mill. Surface treatment of the fillers coated with KH570 was conducted to enhance the wettability and lubrication of fillers in the polymer matrix. According to SEM images and mechanical test, both micro- and submicro-fillers disperse homogeneously in the matrix, and adhesion of submicro-fillers to the matrix is stronger than that of micro-fillers. The submicro-PWO composites had better tensile strength and elongation at break than those composites containing micro-PWO powder, but a relatively higher hardness. The photon shielding test was performed to determine the radiation shielding properties of these composites, which showed that attenuation of gamma-rays for the submicro-PWO composites was substantially enhanced compared to micro-PWO reinforced composites.


2011 ◽  
Vol 418-420 ◽  
pp. 441-444 ◽  
Author(s):  
Feng Lan Li ◽  
Yan Zeng ◽  
Chang Yong Li

Due to many different characteristics such as irregular polygon particle with pointed edges, rough surface and larger content of stone powder, machine-made sand has ignorable effects on the properties of concrete. As the basis for the design of concrete structures, the relations among the basic mechanical properties of concrete such as compressive strength, tensile strength, flexural strength and elastic modulus should be clearly understood. This paper summarizes the test data from the published references, and discusses the relations among these properties by statistical analyses compared with those of ordinary concrete. The results show that the axial compressive strength and the tensile strength can be prospected by the same formulas of ordinary concrete specified in current Chinese design code, but the prospected tensile strength should multiply a reducing coefficient when the strength grade of concrete is lower than C30. The elastic modulus of concrete with machine-made sand is larger than that of ordinary concrete, which should be prospect by the formula in this paper. Meanwhile, the formula of flexural strength is suggested.


2015 ◽  
Vol 804 ◽  
pp. 3-6 ◽  
Author(s):  
Voranuch Thongpool ◽  
Akapong Phunpueok ◽  
Naris Barnthip ◽  
Sarawut Jaiyen

The gamma ray and X-ray shielding properties of PVA containing different proportions of BaSO4 as an aggregate have been investigated. The photon linear attenuation coefficients were measured by using 241Am radioactive source (59.54 keV). Gamma rays were counted by a NaI(Tl) detector. It was found that the shielding efficiency increased when increasing the amount of BaSO4 and specimen thickness. The linear attenuation coefficients were 0.085, 0.125, 0.179, and 0.189 for 0.2, 0.4, 0.6, and 0.8%w/v of BaSO4. The X-ray attenuation test was performed using the diagnostic X-ray machine for energy of 45 kVp. The optical density of X-ray films was investigated. The results showed that the optical density of X-ray film decreased when increasing the amounts of BaSO4.


2021 ◽  
Vol 22 ◽  
pp. 103946
Author(s):  
S.J. Japari ◽  
M.I. Sayyed ◽  
A.K. Yahya ◽  
A.L. Anis ◽  
S.M. Iskandar ◽  
...  

2021 ◽  
Vol 11 (7) ◽  
pp. 3032
Author(s):  
Tuan Anh Le ◽  
Sinh Hoang Le ◽  
Thuy Ninh Nguyen ◽  
Khoa Tan Nguyen

The use of fluid catalytic cracking (FCC) by-products as aluminosilicate precursors in geopolymer binders has attracted significant interest from researchers in recent years owing to their high alumina and silica contents. Introduced in this study is the use of geopolymer concrete comprising FCC residue combined with fly ash as the requisite source of aluminosilicate. Fly ash was replaced with various FCC residue contents ranging from 0–100% by mass of binder. Results from standard testing methods showed that geopolymer concrete rheological properties such as yield stress and plastic viscosity as well as mechanical properties including compressive strength, flexural strength, and elastic modulus were affected significantly by the FCC residue content. With alkali liquid to geopolymer solid ratios (AL:GS) of 0.4 and 0.5, a reduction in compressive and flexural strength was observed in the case of geopolymer concrete with increasing FCC residue content. On the contrary, geopolymer concrete with increasing FCC residue content exhibited improved strength with an AL:GS ratio of 0.65. Relationships enabling estimation of geopolymer elastic modulus based on compressive strength were investigated. Scanning electron microscope (SEM) images and X-ray diffraction (XRD) patterns revealed that the final product from the geopolymerization process consisting of FCC residue was similar to fly ash-based geopolymer concrete. These observations highlight the potential of FCC residue as an aluminosilicate source for geopolymer products.


Sign in / Sign up

Export Citation Format

Share Document