Influence of Thermally Activated Alum Sludge Ash on the near Surface Characteristics of Multiple-Blended Binders Concretes

2015 ◽  
Vol 754-755 ◽  
pp. 421-426 ◽  
Author(s):  
Haider Mohammed Owaid ◽  
Roszilah Hamid ◽  
Mohd Raihan Taha
Keyword(s):  
Inner Core ◽  
Surface Characteristics ◽  
Initial Surface ◽  
Surface Absorption ◽  
Palm Oil Fuel Ash ◽  
Near Surface ◽  
Cement Replacement ◽  
Thermally Activated ◽  
Alum Sludge ◽  
Sludge Ash

This research presents the results of an investigation on the influence of thermally activated alum sludge ash (AASA) as a partial cement replacement on the near-surface characteristics of binary and ternary blended binder (TBB) concretes incorporating silica fume (SF), ground granulated blast furnace slag (GGBS), and palm oil fuel ash (POFA). All of the mixtures were prepared with a water/binder ratio and total binder content of 0.30 and 493 kg/m3, respectively. Initial surface absorption (ISAT) and sorptivity tests were conducted at the age of 28 days. Results indicate decrease in the ISAT and sorptivity values of binary blended binders with 15% AASA cement replacement compared with the control and 20% AASA concretes. A higher replacement level of 20% AASA did not help improve inner core durability but improved surface durability characteristics. All TBB concretes performed better than the binary blends with AASA at the same replacement levels.

scholarly journals Simulating the Effects of Land Surface Characteristics on Planetary Boundary Layer Parameters for a Modeled Landfalling Tropical Cyclone

Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 138
Author(s):  
Yu Wang ◽  
Corene J. Matyas
Keyword(s):  
Tropical Cyclone ◽  
Land Surface ◽  
Friction Velocity ◽  
Inner Core ◽  
Sensible Heat Flux ◽  
Surface Characteristics ◽  
Near Surface ◽  
Land Surfaces ◽  
Rain Rates ◽  
Land Surface Characteristics

This study examined whether varying moisture availability and roughness length for the land surface under a simulated Tropical Cyclone (TC) could affect its production of precipitation. The TC moved over the heterogeneous land surface of the southeastern U.S. in the control simulation, while the other simulations featured homogeneous land surfaces that were wet rough, wet smooth, dry rough, and dry smooth. Results suggest that the near-surface atmosphere was modified by the changes to the land surface, where the wet cases have higher latent and lower sensible heat flux values, and rough cases exhibit higher values of friction velocity. The analysis of areal-averaged rain rates and the area receiving low and high rain rates shows that simulations having a moist land surface produce higher rain rates and larger areas of low rain rates in the TC’s inner core. The dry and rough land surfaces produced a higher coverage of high rain rates in the outer regions. Key differences among the simulations happened as the TC core moved over land, while the outer rainbands produced more rain when moving over the coastline. These findings support the assertion that the modifications of the land surface can influence precipitation production within a landfalling TC.

Strength - Ultrasonic Pulse Velocity Relationship of Thermally Activated Alum Sludge Multiple Blended High Performance Concretes

2013 ◽  
Vol 594-595 ◽  
pp. 521-526 ◽  
Author(s):  
Haider Mohammed Owaid ◽  
Roszilah Hamid ◽  
Mohd Raihan Taha
Keyword(s):  
Compressive Strength ◽  
High Performance ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Ternary Blends ◽  
Exponential Relationship ◽  
Palm Oil Fuel Ash ◽  
Thermally Activated ◽  
Alum Sludge

In this research the performance of ultrasonic pulse velocity in concrete is examined as a nondestructive experiment, in order to estimate compressive strength of thermally activated alum sludge multiple blended high performance concretes (HPC) that contain AAS, silica fume (SF), ground granulated blast furnace slag (GGBS) and palm oil fuel ash (POFA) are determined in both binary and ternary blends of cement. The water/binder ratio and total binder content are fixed at 0.30 and 493 kg/m3 for all types of mixes. The ultrasonic pulse velocity (UPV) of each concrete mix was measured using 100mm cubes after a curing period of ages of 3, 7, 28, 56 and 90 days. The results indicate a very positive exponential relationship between compressive strength and UPV for both binary and ternary blends of HPC mixtures, with coefficient correlation (R2) of 0.889.

scholarly journals Effect of different curing conditions on compressive strength and durability of kenaf fibre reinforced blended cementitious composites

2019 ◽  
Vol 277 ◽  
pp. 03012
Author(s):  
R. Ahmad ◽  
R. Hamid ◽  
S. A. Osman
Keyword(s):  
Compressive Strength ◽  
Accelerated Ageing ◽  
Cementitious Composites ◽  
Curing Conditions ◽  
Thermally Activated ◽  
Kenaf Fibre ◽  
Curing Period ◽  
Alum Sludge ◽  
Sludge Ash ◽  
Strength And Durability

This paper investigates the effect of normal curing (NC), air curing (AC), and burlap curing (BC) under different curing periods on the mechanical strength and durability of kenaf fibre reinforced blended cementitious composites (KFRBCC) with thermally activated alum sludge ash (AASA). The aim is to determine the most efficient condition and period for curing KFRBCC and to assess the effect of accelerated ageing on strength and durability of KFRBCC after wet/dry cycles. Meanwhile, the microstructure of these mixes is observed via scanning electron microscopy (SEM). The KFRBCC is designed to achieve strength beyond 50 MPa after 28 days (d) of curing by adding 2% treated kenaf fibre (KF) and by replacing Ordinary Portland Cement (OPC) with AASA. The findings suggest that compressive strength and durability of KFRBCC with 40% AASA cured under BC after age of 28 d are enhanced. The addition of treated KF with AASA have helped in limiting the reduction in the compressive strength and durability of the KFRBCC, particularly under prolonged curing period.

The Effect of Palm Oil Fuel Ash as a Cementreplacement Material on Self-Compacting Concrete

2014 ◽  
Vol 567 ◽  
pp. 529-534 ◽  
Author(s):  
Belal Alsubari ◽  
Payam Shafigh ◽  
Mohd Zamin Jumaat ◽  
Ubagaram Johnson Alengaram
Keyword(s):  
Compressive Strength ◽  
Palm Oil ◽  
Drying Shrinkage ◽  
Initial Surface ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Surface Absorption ◽  
Palm Oil Fuel Ash ◽  
Fuel Ash ◽  
Oil Fuel

In this study ground palm oil fuel ash (POFA) has been used as cement replacement in percentages of 0%, 10%, and 20% in a self-compacting concrete (SCC). Fresh properties such as slump flow, T50, V-funnel, J-ring, L-box and segregation index; concrete properties such as drying shrinkage strain, initial surface absorption test (ISAT) as well as compressive strength were investigated. Test results showed that substitution of cement with POFA up to 20%, the fresh properties of the concrete fulfilled the requirements of a self-compacting concrete. The results revealed that concrete has higher compressive strength, lower drying shrinkage, and lower initial surface absorption than control mix. The results indicated that POFA can be used up to 20% as a cement replacement material for producing self-compacting concrete.

scholarly journals Initial Surface Absorption of Pozzolan and Polymer Modified Mortar

2013 ◽  
Vol 4 (1) ◽  
pp. 8-12
Author(s):  
Lau Si Kiong ◽  
Norsuzailina Mohamed Sutan
Keyword(s):  
Water Absorption ◽  
Styrene Butadiene Rubber ◽  
Initial Surface ◽  
Butadiene Rubber ◽  
Surface Absorption ◽  
Cement Replacement ◽  
Polymer Addition ◽  
Water Absorption Test ◽  
Pozzolanic Cement ◽  
Styrene Butadiene

This study involves the investigation of water absoption of mortar modified with combinations of polymer and pozzolan by using initial surface water absorption test (ISAT). Since surface of mortar or concrete serves as medium that will be most easily penetrated by moisture that can cause corrosion of reinforcement bars that leads to durability problem, it is imperative to make it durable.Polymer additive and pozzolanic cement replacement used in this study was Styrene Butadiene Rubber (SBR) and Fly Ash (FA) respectively. Mixes were prepared with two water to cement ratios (w/c) of 0.3 and 0.4 with different combinations of 5%, 7% & 10% SBR additive and 10%, 20% and 30% FA cement replacement. Results showed that modified mortar with combination of higher percentages of polymer additive and lower percentages of pozzolonic cement replacement have the lowest initial surface absorption rate compare to unmodified mortar. It can be concluded based on this study that high percentage of polymer addition and low percentage of pozzolanic cement replacement in mortar can enhance its resistance to water absorption.

scholarly journals Strength And Durability Properties Of Steel Fiber Reinforced Self Compacting Concrete

2021 ◽  
Vol 12 (5) ◽  
pp. 818-826
Author(s):  
Sumith Vangara, S Siva Rama Krishna, Venu Malagavelli, K.Tarunkumar, A. Jagadish Babu
Keyword(s):  
Steel Fiber ◽  
Design Procedure ◽  
Steel Fibers ◽  
Second Phase ◽  
Initial Surface ◽  
Fiber Reinforced ◽  
Acid Attack ◽  
Self Compacting Concrete ◽  
Surface Absorption ◽  
Durability Properties

In this present study the durability characteristics of Steel fiber reinforced Self compacting concrete (SFRSCC) is determined for M30 and M40 grade concrete mixes. Along with durability strength and sorptivity is carried out and comparison is made with Plane self-compacting concrete (SCC) by chemical resistances, Initial Surface Absorption Test (ISAT). In the present study, the rational mix design procedure for self-compacting concrete is used. SCC mixes contains large quantity of powder (material whose parcel size is 0.125 mm) to maintain the plastic yield of the properties of fresh concrete as per the general guidelines for design of SCC mixes given in the EFNARC (2005). The present project consists of two phases. In the first phase, SCC mixes for different grades are developed without steel fibers and with steel fibers. The mechanical properties like compressive strength of the different grades were studied. In the second phase, based on the experimental results, durability properties were studied with the using of specimens of size 100 mm × 100 mm × 100 mm. Durability studies like Acid attack factors, Acid-Durability factors, Sulphate attack factors, Sorptivity are studied for the Plain SCC and steel Fiber Reinforced SCC and a comparison is made.

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