Engineering Commons^™

Modelling The Hydrating Behaviour Of Fly-Ash In Blended Cements Using Thermodynamics, Nikki Shaji, Niall Holmes Dr., Mark Tyrer

Conference papers

This paper presents a new method to thermodynamically model the hydration behaviour of fly-ash (FA) blended cements by deriving individual phase descriptions depending on the proportion of FA in the blended cement. The predicted hydrated phase assemblage, pore solution chemistries and pH over 1,000 days of hydration and with increasing FA proportions are presented. The thermodynamic data for the FA phases are derived using oxide proportions and mineral compositions are copied directly into the PHREEQC input file. The FA phases take account of all minerals to give a more accurate description of its behaviour during hydration. The calcium aluminosilicate hydrate …

Review Of Fly-Ash As A Supplementary Cementitious Material, Nikki Shaji, Niall Holmes Dr., Mark Tyrer

Conference papers

This paper presents a review of fly-ash as a Supplementary Cementitious Material (SCM) in concrete in terms of its effects on hydration and durability. The climate change agenda has focused the cement and concrete industry on using low embodied CO2 materials and much effort has been made on incorporating industrial by-products into cement as SCMs. With worldwide cement production (circa 4 billion tonnes) currently accounting for approximately 8% of global CO2 emissions and 7% of industry energy use, the use of suitable SCMs to partially replace cement in concrete is extremely important. However, while coal-fired power stations are in the …

Deriving Discrete Solid Phases From Csh-3t And Cshq End-Members To Model Cement Hydration In Phreeqc, Niall Holmes Dr., Colin Walker, Mark Tyrer, Denis Kelliher

Conference papers

This paper presents a cement hydration model over time using the CEMDATA thermodynamic database and a series of discrete solid phases (DSP) to represent calcium silicate hydrate (C-S-H) as a ternary (CSH-3T) and quaternary (CSHQ) solid solution. C-S-H in cement is amorphous and poorly crystalline with a range of molar Ca/Si ratios = 0.6-1.7 and displays strongly incongruent dissolution behaviour where the release of calcium into solution is several orders of magnitude greater than silicon. It is therefore important that any cement hydration model provides a credible account of this behaviour. C-S-H has been described in the CEMDATA thermodynamic database …

Modelling The Thermoelectric Properties Of Cement-Based Materials Using Finite Element Method And Effective Medium Theory, Lorenzo Stella, Conrad Johnston, Javier Troncoso, Piotr Chudzinski, Esther Orisakwee, Jorge Kohanoff, Ruchita Jani, Niall Holmes Dr., Brian Norton, Xiaoli Liu, Ming Qu, Hongxi Yin, Kazuaki Yazawa

Conference papers

Because of the thermoelectric (TE) effect (or Seebeck effect), a difference of potential is generated as a consequence of a temperature gradient across a sample. The TE effect has been mostly studied and engineered in semiconducting materials and it already finds several commercial applications. Only recently the TE effect in cement-based materials has been demonstrated and there is a growing interest in its potential. For instance, a temperature gradient across the external walls of a building can be used to generate electricity. By the inverse of the TE effect (or Peltier effect), one can also seek to control the indoor …

Performance Modeling And Analysis Of A Thermoelectric Building Envelope For Space Heating, Xiaoli Liu, Ming Qu, Kazuaki Yazawa, Jorge Kohanoff, Piotr Chudzinski, Lorenzo Stella, Brian Norton, Niall Holmes Dr., Ruchita Jani, Hongxi Yin

Conference papers

To provide energy-efficient space heating and cooling, a thermoelectric building envelope (TBE) embeds thermoelectric devices in building walls. The thermoelectric device in the building envelope can provide active heating and cooling without requiring refrigerant use and energy transport among subsystems. Thus, the TBE system is energy and environmentally friendly. A few studies experimentally investigated the TBE under limited operating conditions, and only simplified models for the commercial thermoelectric module (TEM) were developed to quantify its performance. A holistic approach to optimum system performance is needed for the optimal system design and operation. The study developed a holistic TBE-building system model …

Geological Origin As An Input Variable In Reliability-Based Designs: For An Accurate Exploration In Geotechnical Engineering, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

Soil is one of the most difficult materials to characterize realistically, which partly explains the uncertainty between the designs and the geostructures real behavior. Different recommendations have arisen with respect to carrying out field investigations in order to reduce the uncertainties inherent to the soil. However, the field exploration and the implementation of sophisticated geotechnical models have proven to be insufficient to mitigate the geotechnical uncertainty. Therefore, Reliability-Based Designs (RBD) emerge as a decision-making tool through the definition of the probability of failure in conjunction with the typical Factors of Safety. RBD requires a previous understanding of the most appropriate …

Development Of A New Electro-Osmotic Consolidation Apparatus, Yenni Mariana Ramírez-Mazo, Juan Pablo Osorio, Sergio Agudelo

Conference papers

Electro-osmotic consolidation is a ground improvement technique in which a DC voltage is applied to the soil via electrodes, in order to drain the water contained in the pores increasing the effective stress, and thus improving the geotechnical properties of the soil. The technique increases the shear strength, reduces the compressibility, and changes the chemical composition of the saturated soft clayey and silty soils to which it can be applied. Electro-osmotic consolidation has been successfully applied in different projects worldwide. This paper presents the development of a new electro-osmotic consolidation apparatus built at Universidad de Antioquia. Tests were carried on …

Arise (Certcoin)- Inspiring Demand For Sustainable Energy Skills, Barry Mcauley, Paul Mccormack, Andrew Hamilton, Eduardo Rebelo

Conference papers

The European AEC Sector now faces impending challenges over the next decade concerning escalating climate targets. To reach these targets, it vital that the green economy deliver a better-skilled workforce and develops new competencies and methods of working. Training in the domain of digital construction technologies and processes, such as Building Information Modelling (BIM), are now seen as essential upskilling vehicles that must be embraced if the sector is to transition towards a greener agenda. To assist in meeting these training needs a selection of partners from the BIM EPA will partake in the Horizon 2020 ARISE project, aiming to …

An Exploration Of Lean And Bim Synergies With A Focus On Smes In Construction, Barry Mcauley, Marina Andreou, Alan V. Hore, Avril Behan

Conference papers

Small and Medium Enterprises (SME) account for 99.7% of the Irish Construction Industry and contribute to 68% of all employment in the sector. These organisations now find themselves facing the challenge of returning to productive business post the Covid 19 shutdown. More than ever, SMEs must modernise and adapt their business models to embrace new ways of working, such as Lean Construction and Building Information Modelling (BIM), in the absence of clear business incentives. It has proved difficult to persuade SMEs to change their ways of working due to limited finances, internal resources and above all, the cultural shift required …

Digital Construction And Bim Research In Ireland 2016-2020, Barry Mcauley, Roger P. West, Alan V. Hore

Conference papers

As the construction industry opens up post pandemic, new and significant challenges will demand considerable expertise, not least in financial viability, solving the housing crisis and facing the very significant climate change pressures to make the industry less wasteful and less carbon intensive. This presents an excellent opportunity to further inculcate aspects of lean construction, particularly BIM into many aspects of construction not traditionally associated with digital construction, provided the necessary expertise is available and known to exist. Following a well-received recent conference paper summarising BIM-related research published by academics in Ireland’s higher education institutions in 2020, this paper will …

Soil Improvement By Electro-Osmotic Consolidation: Laboratory Testing, Yenni Mariana Ramírez-Mazo, Juan Pablo Osorio, Sergio C. Agudelo-Flórez

Conference papers

Electro-osmotic consolidation is a ground improvement technique that has been successfully implemented on the field and at laboratory scale since the 30s. However, its application has been done primarily through empirical procedures and experience. The determinant variables in the effectiveness and efficiency of the improvement are numerous and require further studies. This paper presents the evaluation of the improvement process of an inorganic low plasticity clay subjected to a 150 V/m voltage during 5780 minutes. The special analysis of the strains showed differential settlements, as well as cracking at the surface and with depth. The consolidations curves obtained follow the …

Thermodynamic Cement Hydration Modelling Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Thermodynamics have been successfully applied to the field of cement hydration science to predict the formation of phase assemblages and pore solution chemistry. For any cement hydration model to be accepted, it must provide accurate forecasts of which solids may form and how the cement will dissolve over time. This is particularly important for the ongoing development of new sustainable cements and understanding their hydration behaviour in service. HYDCEM is a cement hydration model that simulates volumetric changes of cement and gypsum dissolution and product growth that, up to now, assumed which solids would form. In order to improve its …

Predicting Mortar Compressive Strength Using Hydcem, Ewoma Ogoro, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

The compressive strength of mortar is a significant property that will influence its performance in concrete or masonry. Being able to accurately model and predict the mortar compressive strength would be of great benefit to suppliers and end users alike that could possibly reduce the need for multiple physical testing. A section of the original HYDCEM cement hydration model (amoungst others) has been partitioned to focus on predicting the compressive strength of Portland cement and cement-limestone mortars, entitled HYDCEM_CompressiveStrength. The model uses the cement/binder oxide composition along with other inputs to predict the compressive strength development over time. This paper …

Effects Of Accelerated Carbonation Curing On Co2 Sequestration And On The Compressive Strength Of Concrete Masonry Units, Barry Gilroy, Leon Black, David Thompson, Ronan Hogan, Niall Holmes

Conference papers

The global consumption of Portland cement has risen to over 4 billion tonnes per annum. Its manufacture is energy and carbon intensive and approximately 900 kg of CO2 is emitted into the atmosphere for each tonne of Portland cement produced. The International Energy Agency (IEA) roadmap sets out a goal to reduce emissions due to cement production to 18 % below 2006 levels by 2050. Concrete has the potential to re-absorb CO2 by the process of carbonation, where it reacts with CaO in the concrete to form calcium carbonate. Accelerated carbonation curing (ACC) is a technique for curing fresh concrete …

Characterization And Performance Of Cement-Based Thermoelectric Materials, Ruchita Jani, Niall Holmes, Roger P. West, Kevin Gaughan, Xiaoli Liu, Esther Orisakwee, Conrad Johnston, Ming Qu, Jorge Kohanoff, Lorenzo Stella, Hongxi Yin

Conference papers

Thermoelectric materials enable direct conversion of thermal energy to electricity. Ambient heat energy harvesting could be an effective route to convert buildings from being energy consumers to energy harvesters, thus making them more sustainable. There exists a relatively stable temperature gradient (storing energy) between the internal and external walls of buildings which can be utilized to generate meaningful energy (that is, electricity) using the thermoelectric principle. This could ultimately help reduce the surface temperatures and energy consumption of buildings, especially in urban areas. In this paper, ongoing work on developing and characterizing a cement-based thermoelectric material is presented. Samples are …

Improving The Sustainability Of The Built Environment By Training Its Workforce In More Efficient And Greener Ways Of Designing And Constructing Through The Horizon2020 Bimcert Project, Barry Mcauley, Avril Behan

Conference papers

The construction industry consumes up to 50% of mineral resources excavated from nature, generates about 33% of CO2 present in the atmosphere and is responsible for 40% of total global energy through both construction and operation of buildings. The realisation that current pervasive construction practices now face globalization, sustainability, and environmental concerns, as well as ever-changing legislation requirements and new skills needed for the information age has resulted in technologies such as Building Information Modelling (BIM) becoming a key enabler in navigating these barriers. To assist in overcoming these barriers, a number of funding initiatives have been put in place …

Centres Of Excellence And Roadmaps For Digital Transition: Lessons For Ireland’S Construction Industry, Barry Mcauley, Alan Hore, Roger West

Conference papers

Like most sectors in today’s working world, construction businesses are challenged to work in an increasingly digitised world with sophisticated demands from intelligent clients. So much has been written about the inefficiencies of the construction industry, its fragmentation, lack of collaboration, low margins, adversarial pricing, poor productivity, financial fragility, lack of research and development, poor industry image and relatively weak use of digital solutions. The Irish government recognises the importance of digital innovation to address many of the challenges the construction industry faces. With recent high profile reports of escalating spend on signature public sector projects and weak productivity performance …

Bim In Ireland 2019: A Study Of Bim Maturity And Diffusion In Ireland, Barry Mcauley, Alan Hore, Roger West

Conference papers

In 2017, the BIM Innovation Capability Programme team applied five macro BIM maturity conceptual models to capture the capability of the Irish construction industry and assess its BIM maturity. The results found that while Ireland is mature for modelling processes, it is less developed with regards to collaboration processes and policies. Ireland also ranked poorly when it came to regulatory frameworks, measurements and benchmarks compared to a number of countries which also applied the same conceptual models. At the time, the findings highlighted that Ireland’s diffusion dynamic was middle out, meaning that larger organisations or industry associations were pushing the …

An Investigation Into Current Procurement Strategies That Promote Collaboration Through Early Contractor Involvement With Regards To Their Suitability For Irish Public Work Projects, Barry Mcauley, Frederic Lefebvre

Conference papers

Previous research has established that multi-disciplinary collaboration will benefit a construction project throughout its lifecycle. While Lean Construction, Building Information Modelling (BIM), and Integrated Project Delivery (IPD) can all be viewed as separate processes which add independent value to a project, they are more effective when used in partnership with each other. In order to ensure the high levels of collaboration expected for these processes to work in unison, the early involvement of the Contractor is paramount. Early contractor involvement within the design process can ensure a more focused integrated project team, improvement of both constructability and cost certainty, as …

From Roadmap To Implementation: Lessons For Ireland’S Digital Construction Programme, Barry Mcauley, Alan Hore, Roger West

Conference papers

As part of their Future of Construction initiative in 2018 the World Economic Forum published an action plan to accelerate Building Information Modelling adoption. The WEF report highlighted actions that companies, industry organisations and governments are advised to implement to accelerate BIM adoption and better capitalise on delivering better project outcomes. According the authors of the report BIM is seen as the centrepiece of the construction industry’s digital transformation, however they acknowledged that BIM adoption globally remain slow. Anecdotal experience would suggest that BIM usage in Ireland is also very low and that a similar initiative or an adaptation of …

Delivering Energy Savings For The Supply Chain Through Building Information Modelling As A Result Of The Horizon 2020 Energy Bimcert Project, Barry Mcauley, Avril Behan

Conference papers

The global buildings sector is now responsible for 40% of final energy consumption as well as accounting for 33% of energy-related carbon dioxide emissions. This has resulted in a growing urgency to address energy and emissions from buildings and construction, to meet restrictive 2020 targets as specified by the European Union (EU). To achieve these targets a number of funding initiatives have been put in place through Horizon 2020 with a focus on BIM, due to it having the potential to rapidly produce energy outputs that enable design teams to analyse and compare the most cost-effective, energy-efficient options. However, despite …

Modelling The Addition Of Limestone In Cement Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Hydration models can aid in the prediction, understanding and description of hydration behaviour over time as the move towards more sustainable cements continues.

HYDCEM is a new model to predict the phase assemblage, degree of hydration and heat release over time for cements undergoing hydration for any w/c ratio and curing temperatures up to 450C. HYDCEM, written in MATLAB, complements more sophisticated thermodynamic models by predicting these properties over time using user-friendly inputs within one code. A number of functions and methods based on up to date cement hydration behaviour from the literature are hard-wired into the code along with …

Hydcem: A New Cement Hydration Model, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Hydration models are useful to predict, understand and describe the behaviour of different cementitious-based systems. They are indispensable for undertaking long-term performance and service life predictions for existing and new products for generating quantitative data in the move towards more sustainable cements while optimising natural resources. One such application is the development of cement-based thermoelectric applications.

HYDCEM is a new model to predict the phase assemblage, degree of hydration, heat release and changes in pore solution chemistry over time for cements undergoing hydration for any w/c ratio and curing temperatures up to 450C. HYDCEM, written in MATLAB, is aimed at …

Development Of A Framework To Support The Effective Adoption Of Bim In The Public Sector: Lessons For Ireland, Shiyao Kuang, Alan Hore, Barry Mcauley, Roger West

Conference papers

Building Information Modelling (BIM) has been formally adopted by many countries with the promise of creating greater economic, social and sustainability benefits. Several authors and institutions have presented alternative BIM policies and tactics which have been adopted by developed countries. However, there is evidence to indicate that BIM adoption theories are not well established and, in particular, the linkage between BIM public sector adoption strategy outcomes and their contribution to achieving Government policy objectives are underdeveloped. This paper will present the outcome of the first phase of a systematic literature review of published studies (including journal papers and noteworthy international …

Influence Of Limit Equilibrium Methods In The Design Of Contiguous Cantilever Sheet Pile Walls Through Reliability-Based Analysis, Alvaro J. Mattos, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

In geotechnical engineering the design of bored- pile walls is commonly performed in terms of the embedment length (D) defined according to the limit equilibrium methods (also known as balance methods) formulated by Krey, Blum, Rowe, Hansen and the empirical method of Look in sandy soils. The limit equilibrium methods are calculations associated with the shape of the earth pressures distributions in the shaft, earth pressures theories, geotechnical properties and safety factors, while the empirical criteria establish that the relationship between embedment and the free height (H) is of the order of D/H = 1.5. These design methods are complemented …

Prediction Of Flood Hydrograph In Small River Catchments Using System Modelling Approach, Ahmed Nasr, Zeinab Bedri, Loreta Ramanauske

Conference papers

Floods remain to be one of the natural catastrophic disasters with serious adverse social and economic implications on individuals and communities all around the world. In Ireland, frequency of flood events have increased dramatically during the last forty years and is expected to continue to rise primarily due to changes in rainfall and temperature patterns as a result of the global climate change. Small river catchments are usually vulnerable to different types of flooding particularly those associated with “monster” rainfall events, which are characterised by short durations and high intensities. Therefore accurate prediction of flood hydrographs resulting from these rainfall …

Introducing A New Cement Hydration And Microstructure Model, Niall Holmes, Anselm Griffin, Bernard Enright, Denis Keliher

Conference papers

This paper presents a new cement hydration model to predict the microstructure evolution of hydrating tricalcium silicate (C3S). The model is written in MATLAB and employs the continuum approach and integrated particle kinetic relationships to show the change in C3S and the growth of Calcium Silicate Hydrate (C-S-H) and Calcium Hydroxide (CH) in the pore space over time.

Cement hydration is a highly complex process. While hydration models should never completely remove experimental analysis, they are an aid to better understand cement hydration and microstructure development by providing a method to analyse a large number of pastes with different cementitious …

Ireland’S Bim Macro Adoption Study: Establishing Ireland’S Bim Maturity, Barry Mcauley, Alan Hore, Roger West, Mohamad Kassem, Shiyao Kuang

Conference papers

Since 2016 the BIM Innovation Capability Programme (BICP) has captured the capability of the Irish Construction Industry’s and the Higher Education Institutes’ (HEIs) response to the increased requirement for BIM on Irish construction and engineering projects. One of the primary responsibilities of the BICP research team is to collate data to assist the National BIM Council of Ireland in the formulation of a National BIM Roadmap. To assist the Council with this task the BICP research team applied five macro BIM maturity conceptual models to assess Ireland’s BIM maturity. The results from the models were further utilised to develop a …

Stewardship Of International Bim Programmes: Lessons For Ireland, Barry Mcauley, Alan Hore, Roger West, Shiyao Kuang

Conference papers

The support by central government of national Building Information Modelling (BIM) programmes is common throughout the developed world today. To further understand how the different international governments have supported their BIM programmes the BIM Innovation Capability Programme (BICP) research team in Ireland recently completed a comprehensive Global BIM Study to help inform the National BIM Council (NBC) of Ireland in developing a Roadmap to Digital Transition for Ireland’s Construction Sector. This paper details the findings of a more concentrated investigation on a selection of jurisdictions on how particular international BIM programmes are orgainsed, managed and the level of governmental support …

Mass-Balance Assimilative Capacity Model Of Inniscarra Reservoir, Zeinab Bedri, Ahmed Nasr, Sean Crowley

Conference papers

Wastewater arising from the Coachford agglomeration is treated at the existing Coachford Waste Water Treatment Plant (WWTP). This wastewater treatment facility has a primary treatment only with a design capacity of 450 population equivalent (PE) and it discharges the effluent into the Inniscarra Reservoir. The discharge from Coachford WWTP has been identified by the Lower Lee - Owenboy Water Management Unit Action Plan (WMUAP) as a point source pressure on the waters of the Lower Lee - Owenboy catchment and also as a cause of the strongly eutrophic status of Inniscarra Reservoir water quality by the EPA in 2009. Therefore, …