scholarly journals Durability and Abrasion Resistance of Innovative Recycled Pervious Concrete with Recycled Coarse Aggregate of Different Quality under Sulfate Attack

2021 ◽  
Vol 11 (20) ◽  
pp. 9647
Author(s):  
Minqi Hua ◽  
Bo Chen ◽  
Yun Liu ◽  
Hui Liu ◽  
Pinghua Zhu ◽  
...  

Construction and demolition wastes (C&DWs) have raised a large number of ecological and environmental problems. Recycling C&DWs into arecycled concrete aggregate (RCA) will help save natural resources effectively and reduce the negative impact of C&DW on the environment. Innovative pervious concrete (IPC) can mitigate extreme weather disasters, such as rainstorms, and overcome the low strength and poor durability of traditional pervious concrete. In this study, innovative recycled pervious concrete (IRPC) is prepared by combining RCA with IPC, which has broad application prospects and ecological friendliness. This study investigates the effect of RCA quality grades and replacement rates on the mechanical property, permeability, sulfate resistance and abrasion resistance of IRPC. IRPC mixtures were prepared with three different quality grades (high, medium and low qualities) of aggregates named as NA, RCA1 and RCA2. Moreover, the replacement rate of RCA for NA varied as 0%, 25%, 50%, 75% and 100%. The IRPC specimens were tested for compressive strength, mass loss and abrasion resistance after different sulfate wetting-drying cycles of 0, 30 and 60. The results exhibited that the initial compressive strength of all types of IRPC was more than 40 MPa. The compressive strength and mass of most IRPC increased first and then decreased slightly with the passage of a number of sulfate wetting-drying cycles, indicating IRPC has good resistance to sulfate attack. Sulfate attack and the addition of RCA will reduce the abrasion resistance of IRPC. However, when the replacement rate is lower than 50%, and the RCA quality is better (attached mortar content < 25%), the abrasion resistance of IRPC will be improved under sulfate attack. The experimental results might be useful as a reference and design methodology for employing IRPC in pavement applications in the future.

2019 ◽  
Vol 258 ◽  
pp. 04011
Author(s):  
Atur P. N. Siregar ◽  
Emma L. Pasaribu ◽  
I Wayan Suarnita

Coarse aggregate is the dominant constituent in concrete. Aggregate hardness is a variable needed to investigate in determining its effect on the critical stress intensity factors (KIC), dissipated fracture energy (Gf) and compressive strength (fc’) of the concrete. The hardness of coarse aggregate based on Los Angeles abrasion values of 16.7%., 22.6%, and 23.1% was used incorporated with Portland Composite Cement (PCC), and superplasticizer to create specimens. Cubes of 150x150x150 mm were employed to determine the fc’, and four beam sizes: 50x100x350 mm, 50x150x500 mm, 50x300x950 mm and 50x450x1250 mm were engaged to determine KIC and Gf. The fc’ and Gf of specimens manufactured by three different hardness of coarse aggregates were 45, 43, 40 MPa and 89.4, 54.0, 56.3 N/m respectively. KIC of specimens was 138.9, 119.4 and 114.1 MPa.mm1/2 for beam size of 50x100x350 mm; 148.2, 115.8 and 108.8 MPa.mm1/2 for beam size of 50x150x500 mm; 230.9, 183.1 and 157.9 MPa.mm1/2 for beam size of 50x300x950 mm; and 293.2, 248.1 and 244.3 MPa.mm1/2 for beam size of 50x450x1250 mm. Experimental results showed that decreasing hardness of coarse aggregate was found to have significant effect on the fracture toughness rather than on the compressive strength of concrete.


2019 ◽  
Vol 801 ◽  
pp. 391-396
Author(s):  
Janardhan Prashanth ◽  
Harish Narayana ◽  
Ramji Prasad

In this paper comparative study on the compressive strength and permeability of pervious concrete with and without fine aggregate is done. Sand and LLDPE (Linear low density polythene) with varying percentages are used as fine aggregates. Sand is added in percentages of 5%, 10% and 15% of the coarse aggregate in all the mixes. LLDPE powder is added in the percentage of 5%, 10% and 15% of the coarse aggregate in all the mixes. With the addition of fine aggregate the compressive strength of the pervious concrete increases but permeability reduces. The results show that the pervious concrete with LLDPE powder there is a considerable increase in compressive strength as compared to no-fines mix and mix with sand as fine aggregate. The study recommends the use of eco-friendly pervious concrete with LLDPE powder as an alternative to the existing pavements with low volume traffic.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
W. C. Tang ◽  
P. C. Ryan ◽  
H. Z. Cui ◽  
W. Liao

The utilisation of recycled concrete aggregate (RCA) in Self-Compacting Concrete (SCC) has the potential to reduce both the environmental impact and financial cost associated with this increasingly popular concrete type. However, to date limited research exists exploring the use of coarse RCA in SCC. The work presented in this paper seeks to build on the existing knowledge in this area by examining the workability, strength, and fracture properties of SCCs containing 0%, 25%, 50%, 75%, and 100% coarse RCA. The experimental programme indicated that at RCA utilisation levels of 25% to 50% little or no negative impact was observed for strength, workability, or fracture properties, with the exception of a slight reduction in Young’s modulus.


2020 ◽  
Vol 38 (11A) ◽  
pp. 1706-1716
Author(s):  
Wasan I. Khalil ◽  
Qias J. Frayyeh ◽  
Mahmood F. Ahmed

The purpose of this work is to investigate the possibility to recycled and reused of waste clay brick and waste plastic as constituents in the production of green Geopolymer concrete paving bricks. Powder of clay brick waste (WBP) was used as a partial replacement of Metakaolin (MK) in Geopolymer binder. Moreover, recycled clay brick waste aggregate (BA) and plastic waste aggregate (PL) were incorporated as coarse aggregate in mixtures of Metakaolin based Geopolymer concrete (MK-GPC) pavement bricks. Six types of mixtures were prepared and cast as pavement bricks with dimensions of 150×150×100 mm. All samples have been tested for compressive strength, water absorption and abrasion resistance at age of 28 days; and compared the results with the requirements of Iraqi specification No.1606-2006. The MK-GPC pavement bricks present a compressive strength of 31-47MPa, water absorption of 3.66% to5.32% and abrasion resistance with groove length between 21.78mm to 18.91 mm. These types of pavement bricks are classified as a medium to light capacity for weight loading, and it is possible to be used in wide range of paving applications, especially in aggressive wearing environment.


Author(s):  
Suwendy Arifin Et.al

Pervious concrete or non-fine concrete is a simple form of lightweight concrete made by eliminating the use of fine aggregates. As a result of not using fine aggregate in pervious concrete, then created a cavity filled with air and water can be passed. This cavity resulted in reduced density of the concrete as well as the reduced amount of area that needs to be covered by cement paste, thereby reducing the compressive strength. To increase the compressive strength of pervious concrete, in this study will utilize waste material. The waste material is the cocnut shell ash and coconut shell to strengthen the coarse aggregate bonds, so it is expected to increase the compressive strength along with the increase in permeability. Thus, in this study will replace part of the coarse aggregate with coconut shell with percentage 0%, 2,5%, 5%, 7,5%, 10% and partially replace cement with coconut shell ash with percentage 0%, 2,5%, 5%, 7,5%


Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 430
Author(s):  
Jawad Ahmad ◽  
Rebeca Martínez-García ◽  
Jesús de-Prado-Gil ◽  
Kashif Irshad ◽  
Mohammed A. El-Shorbagy ◽  
...  

The current practice of concrete is thought to be unsuitable because it consumes large amounts of cement, sand, and aggregate, which causes depletion of natural resources. In this study, a step towards sustainable concrete was made by utilizing recycled concrete aggregate (RCA) as a coarse aggregate. However, researchers show that RCA causes a decrease in the performance of concrete due to porous nature. In this study, waste glass (WG) was used as a filler material that filled the voids between RCA to offset its negative impact on concrete performance. The substitution ratio of WG was 10, 20, or 30% by weight of cement, and RCA was 20, 40, and 60% by weight of coarse aggregate. The slump cone test was used to assess the fresh property, while compressive, split tensile, and punching strength were used to assess the mechanical performance. Test results indicated that the workability of concrete decreased with substitution of WG and RCA while mechanical performance improved up to a certain limit and then decreased due to lack of workability. Furthermore, a statical tool response surface methodology was used to predict various strength properties and optimization of RCA and WG.


2018 ◽  
Vol 162 ◽  
pp. 02020 ◽  
Author(s):  
Nisreen Mohammed ◽  
Kaiss Sarsam ◽  
Mazin Hussien

Use of Recycled Coarse Aggregate (RCA) in concrete can be described in terms of environmental protection and economy. This paper deals with the mechanical properties of concrete compressive strength, splitting tensile strength, modulus of elasticity, and modulus of rupture. Three kinds of concrete mixtures were tested, concrete made with Natural Coarse Aggregate (NCA) as a control concrete and two types of concrete made with recycled coarse aggregate (50% and 100% replacement level of coarse recycled aggregate). These kinds of concrete were made with different targets of compressive strength of concrete f ’c (35MPa) and (70 MPa). Fifty specimens were tested of the fresh and hardened properties of concrete. The waste concrete from laboratory test cubes was crushed to produce the Recycled Coarse Aggregate used in recycled concrete. A comparative between the experimental results of the properties for fresh and hardened concrete is presented in the paper. Recycled aggregate concrete (RCA) had a satisfactory performance despite the replacement ratios. It was found using the size of Recycled Coarse Aggregate (RCA) of (5-14) mm has quite similar in performance with the same size of Natural Coarse Aggregate (NCA), it is necessary to use high quality of recycled concrete (with low levels of impurities). Recycled aggregate as an alternative to natural aggregates -seems quite successful.


Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 593
Author(s):  
Haining Geng ◽  
Qing Xu ◽  
Saiful B. Duraman ◽  
Qiu Li

Pervious concrete is made of cementitious materials, coarse aggregate, water and additives, with characteristic macro- and meso-connected pore structure, which enables the acceptable mechanical properties and high water permeability for pavement and road applications. In this study, the effect of rheology of fresh alkali-activated slag paste on the sedimentation of paste on the bottom of pervious concrete, meso-structure, connected porosity, mechanical properties and water permeability was investigated by a range of analytical techniques through varying the equivalent alkali content to control the rheology of fresh paste in the pervious concrete. The compressive strength of pervious concrete was related to the percentage area of paste and the average thickness of paste on the surface of coarse aggregate. The tensile strength and water permeability were correlated to the connected porosity of pervious concrete and the rheology of fresh paste. A relative lower fluidity, higher viscosity and shear stress of fresh alkali-activated slag paste favoured lower sedimentation of paste on the bottom of pervious concrete, higher connected porosity, tensile strength and water permeability. There was no correlation between compressive strength and tensile strength of pervious concrete.


2021 ◽  
Author(s):  
Medhat Shehata ◽  
Jonathan Andal ◽  
Philip Zacarias

<p>This study focuses on evaluating recycled concrete aggregate (RCA) of high quality produced through a protocol that preserves the original properties of the concrete to be recycled. Concrete with RCA of preserved quality was compared to concrete with commercially available RCA. A total of 29 mixes were tested with RCA replacement ranging from 30% to 100% of the coarse aggregate. Results showed that concrete with RCA of preserved quality performed significantly better in compressive strength, drying shrinkage, and salt scaling resistance. Furthermore, the use of 30% RCA with preserved quality produced concrete of comparable quality to that of concrete with natural aggregate.</p>


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