Effect of Steel Fibers on Properties of Modified Reactive Powder Concrete
Farah Saeed Rasheed,
Khalil Ibrahim Aziz
Issue:
Volume 5, Issue 1, June 2021
Pages:
1-6
Received:
9 January 2021
Accepted:
6 February 2021
Published:
30 March 2021
Abstract: This paper provides the result of an investigation to use of crushed brick as aggregates which was collected from the demolition waste of buildings from different sites then crushed with (maximum size 10 mm) in producing modified reactive concrete MRPC, which was presented by replacement the cementation binder (cement +silica fume) of original reactive powder concrete by 25% of crushed brick aggregates. The objective of this work is to study the effect of different type of steel fibers added in ratio 1% on the flowability and mechanical properties of reactive powder concrete and modified reactive powder concrete, which was micro steel fiber and hooked end steel fiber. The mechanical properties are examined by the tests of compressive strength, split tensile strength and flexural strength. The results showed that the compressive strength at 28 days of ORPC was 126.46 MPa, 120 MPa for the two types of steel fibers micro, hooked respectively. For the mix MRPC with micro, hooked the compressive strength at 28 days decreased by 1.53% and 1.15%, compared with those of the RPC made with micro, hooked steel fibers. And observed from the experimental results that two mixtures (RPC and MRPC) with micro steel fiber gave higher mechanical properties compared with the hook end.
Abstract: This paper provides the result of an investigation to use of crushed brick as aggregates which was collected from the demolition waste of buildings from different sites then crushed with (maximum size 10 mm) in producing modified reactive concrete MRPC, which was presented by replacement the cementation binder (cement +silica fume) of original reac...
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Two Dimensional Advection Diffusion Equations in Unstable Case
Khaled Sadek Mohamed Essa,
Sawsan Ibrahim Mohamed El Saied
Issue:
Volume 5, Issue 1, June 2021
Pages:
7-12
Received:
12 June 2021
Accepted:
29 June 2021
Published:
9 July 2021
Abstract: The aim of this work is to solve the diffusion equation in two dimensions to obtain normalized crosswind integrated concentrations using the Laplace Transform technique, taking into account that the wind speed is constant but the vertical diffusivity differs from the friction velocity and the Monin -Obukhov length. A comparison of the calculated values and the observed concentrations taken from the northern part of Copenhagen, Denmark and also Inshas, Cairo, Egypt for trace hexafluoride (SF6) through unstable condition were made. It has compared the current and observed concentration one finds that the current concentration agreement well with the observed data. The results showed an agreement between the measurements and the simulations. The values for NMSE and FB are relatively close to zero, and COR, FA2 is relatively close to one.
Abstract: The aim of this work is to solve the diffusion equation in two dimensions to obtain normalized crosswind integrated concentrations using the Laplace Transform technique, taking into account that the wind speed is constant but the vertical diffusivity differs from the friction velocity and the Monin -Obukhov length. A comparison of the calculated va...
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