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Article
Publication date: 15 November 2011

Chunqi Lian, Yan Zhuge and Simon Beecham

Porous concrete is a mixture of open‐graded coarse aggregate, water and cement. It is also occasionally referred to as no‐fines concrete or pervious concrete. Due to its…

Abstract

Purpose

Porous concrete is a mixture of open‐graded coarse aggregate, water and cement. It is also occasionally referred to as no‐fines concrete or pervious concrete. Due to its high infiltration capacity, it is viewed as an environmentally sustainable paving material for use in urban drainage systems since it can lead to reduced flooding and to the possibilities of stormwater harvesting and reuse. However, the high porosity is due in the main part to the lack of fine aggregate particles used in the manufacture of porous concrete. The purpose of this paper is to present a numerical method to understand more fully the structural properties of porous concrete. This method will provide a useful tool for engineers to design with confidence higher strength porous concrete systems.

Design/methodology/approach

In the method, porous concrete is modelled using a discrete element method (DEM). The mechanical behaviour of a porous concrete sample subjected to compressive and tensile forces is estimated using two‐dimensional Particle Flow Code (PFC2D).

Findings

Three numerical examples are given to verify the model. A comprehensive set of micro‐parameters particularly suitable for porous concrete is proposed. The accuracy and effectiveness of simulation are confirmed by comparison with experimental results and empirical equations.

Originality/value

The experimental investigations for porous concrete described in this paper have been designed and conducted by the authors. In addition, the type of two dimensional PFC analysis presented has rarely been used to model porous concrete strength characteristics and from the results presented in this paper, this analysis technique has good potential for predicting its mechanical properties.

Details

Engineering Computations, vol. 28 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 6 August 2018

Sayed-Farhad Mousavi, Hojat Karami, Saeed Farzin and Ehsan Teymouri

This study aims to use porous concrete and mineral adsorbents (additives) for reducing the quantity and improving the quality of urban runoff.

Abstract

Purpose

This study aims to use porous concrete and mineral adsorbents (additives) for reducing the quantity and improving the quality of urban runoff.

Design/methodology/approach

The effects of adding mineral adsorbents and fine grains to porous concrete is tested for increasing its performance in improving the quality of urban runoff. Two levels of sand (10 and 20 per cent) and 5, 10 and 15 per cent of zeolite, perlite, LECA and pumice were added to the porous concrete. Unconfined compressive strength, hydraulic conductivity (permeability) and porosity of the porous concrete specimens were measured. Some of the best specimens were selected for testing the improvement of runoff quality. A rainfall simulator was designed and the quality of the runoff was investigated for changes in electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS) and chemical oxygen demand (COD).

Findings

The results of this study showed that compressive strength of the porous concrete was increased by adding fine grains to the concrete mixture. Fine grains decreased the permeability and porosity of the samples. Zeolite had the highest compressive strength. Samples having pumice own maximum permeability. Samples which had perlite, had the least compressive strength and permeability. Because of the fast flow of runoff water in the porous slab and its low thickness, sufficient time was not provided for effective functioning of the additives, and the removal percentage of the pollution parameters was low.

Originality/value

Porous concrete can ameliorate both quantity and quality of the urban runoff.

Details

World Journal of Engineering, vol. 15 no. 4
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 1 November 2002

Bernhard A. Schrefler, Carmelo E. Majorana, Gabriel A. Khoury and Dariusz Gawin

This paper presents the physical, mathematical and numerical models forming the main structure of the numerical analysis of the thermal, hydral and mechanical behaviour of…

Abstract

This paper presents the physical, mathematical and numerical models forming the main structure of the numerical analysis of the thermal, hydral and mechanical behaviour of normal, high‐performance concrete (HPC) and ultra‐high performance concrete (UHPC) structures subjected to heating. A fully coupled non‐linear formulation is designed to predict the behaviour, and potential for spalling, of heated concrete structures for fire and nuclear reactor applications. The physical model is described in more detail, with emphasis being placed upon the real processes occurring in concrete during heating based on tests carried out in several major laboratories around Europe as part of the wider high temperature concrete (HITECO) research programme. A number of experimental and modelling advances are presented in this paper. The stress‐strain behaviour of concrete in direct tension, determined experimentally, is input into the model. The hitherto unknown micro‐structural, hydral and mechanical behaviour of HPC/UHPC were determined experimentally and the information is also built into the model. Two examples of computer simulations concerning experimental validation of the model, i.e. temperature and gas pressure development in a radiatively heated HPC wall and hydro‐thermal and mechanical (damage) performance of a square HPC column during fire, are presented and discussed in the context of full scale fire tests done within the HITECO research programme.

Details

Engineering Computations, vol. 19 no. 7
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 March 1965

J. Franquin

This article, by a noted French authority, summarises the work done in French territories over the past 30 years, and presents the conclusions derived from these long and…

Abstract

This article, by a noted French authority, summarises the work done in French territories over the past 30 years, and presents the conclusions derived from these long and thorough investigations. The author is a chemical and geological engineer and is a Docteur ès Sciences of the University of Nancy. He has long been associated with prestressed concrete work and is currently the President of the Concrete Group of the Commission Europèenne de la Corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 12 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 23 November 2018

Kabiru Abdullahi Ahmad, Norhidayah Abdul Hassan, Mohd Ezree Abdullah, Munder A.M. Bilema, Nura Usman, Al Allam Musbah Al Allam and Mohd Rosli Bin Hainin

In order to fully understand the properties of porous asphalt, investigation should be conducted from different point of views. This is from the fact that porous asphalt…

Abstract

Purpose

In order to fully understand the properties of porous asphalt, investigation should be conducted from different point of views. This is from the fact that porous asphalt mixture designed with the same aggregate gradation and air void content can give different infiltration rate due to the different formation of the internal structure. Therefore, the purpose of this paper is to investigate the micro-structural properties and functional performance of porous asphalt simultaneously.

Design/methodology/approach

The aim is to develop imaging techniques to process and analyze the internal structure of porous asphalt mixture. A few parameters were established to analyze the air void properties and aggregate interlock within the gyratory compacted samples captured using a non-destructive scanning technique of X-ray computed tomography (CT) throughout the samples. The results were then compared with the functional performance in terms of permeability. Four aggregate gradations used in different countries, i.e. Malaysia, Australia, the USA and Singapore. The samples were tested for resilient modulus and permeability. Quantitative analysis of the microstructure was used to establish the relationships between the air void properties and aggregate interlock and the resilient modulus and permeability.

Findings

Based on the results, it was found that the micro-structural properties investigated have successfully described the internal structure formation and they reflect the results of resilient modulus and permeability. In addition, the imaging technique which includes the image processing and image analysis for internal structure quantification seems to be very useful and perform well with the X-ray CT images based on the reliable results obtained from the analysis.

Research limitations/implications

In this study, attention was limited to the study of internal structure of porous asphalt samples prepared in the laboratory using X-ray CT but can also be used to assess the quality of finished asphalt pavements by taking core samples for quantitative and qualitative analysis. The use of CT for material characterization presents a lot of possibilities in the future of asphalt concrete mix design.

Originality/value

Based on the validation process which includes comparisons between the values obtained from the image analysis and those from the performance test and it was found that the developed procedure satisfactorily assesses the air voids distribution and the aggregate interlock for this reason, it can be used.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 2 October 2017

Kabiru Abdullahi Ahmad, Mohd Ezree Abdullah, Norhidayah Abdul Hassan, Hussaini Ahmad Daura and Kamarudin Ambak

Porous asphalt has been used for than 50 years, but it was originally developed in 1970 at Franklin institute in Philadelphia, Pennsylvania. By 1974 the first formalized…

Abstract

Purpose

Porous asphalt has been used for than 50 years, but it was originally developed in 1970 at Franklin institute in Philadelphia, Pennsylvania. By 1974 the first formalized procedure was created by the federal highway administration to design mixtures. Many researches on porous asphalt mixture have been conducted for the past two decades. However, there remains some concern about the potential adverse impacts of infiltrated surface water on the underlying groundwater. The purpose of this paper is to presents a short review on the application of porous asphalt pavement stormwater treatment.

Design/methodology/approach

In this paper, a critical review on history and benefits is presented followed by review of general studies of using porous asphalt pavement, and some recent scientific studies that examine potential contamination of soil and groundwater because of infiltration systems.

Findings

This paper indicates that porous asphalt pavement is more efficient than conventional pavements in terms of retaining pollutants, improving the quality of water and runoff while maintaining infiltration.

Originality/value

This paper may also help reduce land consumption by reducing the need for traditional storm-water management structures. However, on the other hand, the priority objectives which is minimizing increased flooding and pollution risks while increasing performance efficiency and enhancing local environmental quality-of-life is achieved.

Details

World Journal of Engineering, vol. 14 no. 5
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 9 August 2018

Bo Da, Hongfa Yu, Haiyan Ma and Zhangyu Wu

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand…

Abstract

Purpose

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater and cement can be widely used for the construction of ports, levees, airports and roads to achieve practical engineering values. However, the naturally porous coral structure and abundant Cl in the seawater and coral lead to extremely severe reinforcement corrosion for CASC. It is well known that Cl is the main cause of reinforcement corrosion in the marine environment. Therefore, it is necessary to research the reinforcement corrosion of CASC in the marine environment.

Design/methodology/approach

In this study, linear polarization resistance was adopted to test the linear polarization curves of reinforcement in CASC with different exposure times. Ecorr, Rp, Icorr and Vcorr were calculated according to the weak electrochemical polarization theory and Stern–Geary formula. The effects of concrete cover thickness, exposure time, reinforcement types and inhibitor on reinforcement corrosion in CASC were analysed. The reinforcement corrosion degradation rule was determined, which provided theoretical support for the durability improvement, security assessment, service life prediction and service quality control of CASC structures in marine islands and reef engineering.

Findings

The corrosion resistance was enhanced with increased concrete cover thickness, and the concrete cover thickness for organic new coated steel should be at least 5.5 cm to reduce the reinforcement corrosion risks in CASC structures. The corrosion resistance of different types of reinforcements followed the rule: 2205 duplex stainless steel > 316 stainless steel > organic new coated steel > zinc-chromium coated steel > common steel. In the early exposure stage, the anti-corrosion effectiveness of the calcium nitrate inhibitor (CN) was superior to that for the amino alcohol inhibitor (AA). With the extension of exposure time, the decreasing rate of anticorrosion effectiveness of CN was higher than that of AA.

Originality/value

Reinforcement corrosion of CASC in a marine environment was studied. Concrete cover thickness, exposure time, reinforcement type and inhibitor influenced the reinforcement corrosion were investigated. New technique of reinforcement anti-corrosion in marine engineering was proposed. Possible applications of CASC in marine engineering structures were suggested.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 30 April 2021

Carla Aramouny

This paper presents the applied research and design work on innovative and sustainable building products developed by an undergraduate architecture seminar course. It…

Abstract

Purpose

This paper presents the applied research and design work on innovative and sustainable building products developed by an undergraduate architecture seminar course. It presents the case for innovative uses of cement-based products, while framing the proposals within a global shift toward environmentally responsive and bio-integrated materials.

Design/methodology/approach

The methodology utilizes a process of hybridization between digital fabrication and analog making methods that is framed within the larger design discourse and that intersects the digital design process with material know-how. The approach engages local problematics and applies advanced technology and the integration of natural behaviors to develop a rich applied design method.

Findings

Through the presented work and proposed building products, critical findings and outcomes emerge, ones that relate to the design process itself and others to the designed products.

Originality/value

The research presented here proposes novel approaches to cement-based building systems utilizing digital and analog fabrication, and original design solutions that engage with their context and provide active and crucial environmental performance.

Details

Archnet-IJAR: International Journal of Architectural Research, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2631-6862

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Article
Publication date: 2 July 2020

Toqa AL-Kasasbeh and Rabab Allouzi

This research is part of a project that aims to investigate using foamed concrete structurally in houses. Foamed concrete has a porous structure that makes it light in…

Abstract

Purpose

This research is part of a project that aims to investigate using foamed concrete structurally in houses. Foamed concrete has a porous structure that makes it light in weight, good in thermal insulation, good in sound insulation and workable.

Design/methodology/approach

An experimental program is conducted in this research to investigate the behavior of polypropylene fiber reinforced foam concrete beams laterally reinforced with/without glass fiber grid.

Findings

The results proved the effectiveness and efficiency of using glass fiber grid as lateral reinforcements on the shear strength of reinforced foam concrete ribs, in reducing the cracks width and increasing its shear capacity, contrary to using glass fiber grid of reinforced foam concrete beams since glass fiber grid did not play good role in beams.

Originality/value

Limited literature is available regarding the structural use of foam concrete. However, work has been done in many countries concerning its use as insulation material, while limited work was done on structural type of foam concrete.

Details

International Journal of Structural Integrity, vol. 12 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 7 July 2017

Duncan Cree, Prosper Pliya, Mark F. Green and Albert Noumowé

The purpose of this paper is to evaluate high strength concrete (HSC) containing polypropylene fibers (PP-fibers) at high temperature under a compressive load.

Abstract

Purpose

The purpose of this paper is to evaluate high strength concrete (HSC) containing polypropylene fibers (PP-fibers) at high temperature under a compressive load.

Design/methodology/approach

The use of PP fibers in HSC is known to reduce and at times eliminate the risk of spalling. HSC containing 0, 1 and 2 kg/m3 of PP-fibers were subjected to various temperatures from 20°C to 150°C, 300°C and 450°C and evaluated in a “hot condition”. One group of specimens was in a non-stressed condition during heating (unstressed hot), while a second group was subjected to an initial preload of 40 per cent of the room temperature compressive strength during the heating (stressed hot).

Findings

Results showed that stressed concrete containing PP-fibers had lower thermal gradients (the temperature difference between the surface and center temperatures as a function of radial distance) and a decrease in relative porosity. However, the compressive strength of stressed specimens was improved with or without fibers as compared to that of the unstressed HSC. The increased stress levels due to concrete expansion at elevated temperature were also reported. The PP-fibers did not have a significant effect on the compressive strength of stressed concrete as compared to the unstressed state.

Originality/value

This paper reports the compressive strength of PP-fibers in HSC at elevated temperature with and without a pre-load.

Details

Journal of Structural Fire Engineering, vol. 8 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

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