Holistic modelling approach for special concrete: from fresh- to hardened-state

In the construction industry, the design of dimensions and material properties is generally separated from the design of material composition and of the production processes used. Such divide is enabled by robust construction materials (like concrete) little affected by production processes if minimum precautionary measures are in place. The same does not hold true for special concrete types; whose higher sensibility compels a shift towards more comprehensive approaches that assimilate the production process in a holistic design. The design driven by integrated numerical simulations encompassing from production to the long-term performance is already ordinary in the manufacturing of plastic and metallic parts. Nevertheless, it remains an alien to the construction industry. The objective of this paper is to review existing studies that might underpin this holistic design approach in construction and show some of its capabilities. Advanced modelling strategies available to simulate the behaviour from the fresh- to the hardened-state are discussed for the cases of pervious concrete and fibre reinforced concrete. This approach provides a deeper insight about the material behaviour and aids to a new level of numerical optimisation of their compositions and production processes, unlocking a potential transformation of the modus operandi of the construction industry.

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A study on industrial-scale waste utilization in construction material production: the use of fly ash in GRP composite pipe

Materiales de Construcción ◽

10.3989/mc.2020.12719 ◽

2020 ◽

Vol 70 (340) ◽

pp. 234

Author(s):

A. Beycioğlu ◽

H. Mis ◽

E. D. Güner ◽

H. Güner ◽

N. Gökçe

Keyword(s):

Tensile Strength ◽

Fly Ash ◽

Construction Material ◽

Construction Materials ◽

Waste Utilization ◽

Industrial Wastes ◽

Glass Fiber Reinforced ◽

Axial Tensile ◽

Long Term Performance ◽

Term Performance

This study presents a new approach to the utilization of industrial by-products in construction materials by using fly ash (FA) in the production of glass fiber-reinforced polyester (GRP) pipe. The FA was substituted by 10% and 20% (by weight of sand) in the mixtures to produce GRP pipes of 350 mm in diameter and 6 m in length for testing. Stiffness modulus (SM), axial tensile strength (ATS), and hoop tensile strength (HTS) tests were conducted on the produced GRP pipes and their elasticity modulus (EM) values were also calculated. To observe the microstructure of the GRP pipes and the interfacial transition zone of the layers, SEM and microscopic analyses were performed. Furthermore, a strain-corrosion test was conducted to obtain information about long term-performance of samples. The results showed that the FA-filled GRP pipes were found to meet the requirements of the related standards, and that the use of FA in the GRP pipe industry may be an important alternative approach to the utilization of industrial wastes via effective recycling mechanisms.

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A Review on the Performance of Concrete Containing Non-Potable Water

Applied Sciences ◽

10.3390/app11156729 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6729

Author(s):

Babar Ali ◽

Rawaz Kurda ◽

Jorge de Brito ◽

Rayed Alyousef

Keyword(s):

Construction Industry ◽

Potable Water ◽

Water Footprint ◽

State Of The Art ◽

Construction Materials ◽

Negative Effects ◽

Different Types ◽

Hardened State ◽

Technical Properties ◽

Industrial Sewage

Construction industries consume huge amounts of potable water during activities such as washing of aggregates, stone crushing, manufacturing, and curing of concrete, mortars, grouts, and wetting of masonry bricks. It is also responsible for wastewater generated during the finishing and cleaning of buildings and construction equipment. Therefore, the water-footprint of construction industry cannot be ignored to reach the state-of-the art sustainability. This study reviewed the technical properties of construction materials made with non-potable water (NPW), i.e., domestic and industrial sewage. The study identified the positive and negative effects of non-potable water on the fresh- and hardened-state properties of concrete. This study also identified the gaps in the literature that can be analysed in order to produce reliable information related to the use of different types of NPW on the properties of concrete.

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The Need to Uplift Quality Control and Quality Assurance for Specialized Concrete Crack Repair in the South African Construction Industry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1129.416 ◽

2015 ◽

Vol 1129 ◽

pp. 416-421

Author(s):

Jannes Bester ◽

Deon Kruger

Keyword(s):

Quality Control ◽

Quality Assurance ◽

Construction Industry ◽

Poor Performance ◽

Repair Process ◽

Patch Repair ◽

Patch Repairs ◽

Long Term Performance ◽

Term Performance

Concrete patch repair is becoming an important facet of the civil construction industry when considering the large quantity of exposed concrete surfaces requiring maintenance and rehabilitation during its design life cycle. Patch repairs are more often than not done with a specialized polymer-modified mortar which requires adequate quality control and quality assurance during application and curing to ensure long-term success. Unfortunately, there have been many patch repair projects where there has been poor performance of the patch repairs resulting in debonding, cracking and discolouration. In this paper, poor or inadequate quality control during the patch repair process is investigated as one of the possible reasons for poor performance and premature failure . It is postulated that because of the lack of adequate knowledge and understanding of the repair material and the repair process by the various stakeholders (applicator, supplier, consultant and client), deficiencies in the quality control and quality assurance before, during and after the repair project often exists. In many patch repair projects, the responsibility for the successful completion of the patch repair work and the assessment of long term performance of patch repairs is not fully embraced by all of the parties involved.This postulation has led to the research, by using questionnaires designed specifically for the four different stakeholder categories of the concrete repair industry. The results indicate that there is very little discussion amongst the stakeholders regarding quality control and acceptance criteria when performing concrete patch repairs, neither for the identification of patch repair failure directly after the completion of the patch repair, nor for long term performance of the patch repairs.

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