Chemical and Thermal Characterization of Cement Mortar Containing Ground Palm Oil Fuel Ash as a Partial Cement Replacement

This study investigates the influence of using ground palm oil fuel ash(G-POFA) from 10%-30% as cement replacement(by weight) on the cement mortar's pH under various curing conditions. These findings were supplemented by thermal gravimetric analysis(TGA). Moreover, the resistance of G-POFA blended cement mortars to water absorption and sorptivity was determined. Further, the k-value test was carried out to explain the pozzolanic and filler behavior of G-POFA and to support the results obtained from TGA. It was found that there was no significant impact of several curing conditions on the pH of mortars. The mortar with 10% G-POFA in replacement of cement(G-POFA-10) exhibited the best resistance against water absorption and sorptivity.

Smart contract applications in the built environment: How prepared are Nigerian construction stakeholders?

Studies have demonstrated that advanced technology,such as smart contract applications,can enhance both pre-and post-contract administration within the built environment sector.Smart contract technology,exemplifying blockchain technologies,has the potential to improve transparency,trust,and the security of data transactions within this sector.However,there is a dearth of academic literature concerning smart contract applications within the construction industries of developing countries,with a specific focus on Nigeria.Consequently,this study seeks to explore the relevance of smart contract technology and address the challenges impeding its adoption,offering strategies to mitigate the obstacles faced by smart contract applications.To investigate the stakeholders,this research conducted 14 virtual interview sessions to achieve data saturation.The interviewees encompassed project management practitioners,senior management personnel from construction companies,experts in construction dispute resolution,professionals in construction software,and representatives from government construction agencies.The data obtained from these interviews underwent thorough analysis employing a thematic approach.The study duly recognizes the significance of smart contract applications within the sector.Among the 12 identified barriers,issues such as identity theft and data leakage,communication and synchronization challenges,high computational expenses,lack of driving impetus,excessive electricity consumption,intricate implementation processes,absence of a universally applicable legal framework,and the lack of a localized legal framework were recurrent impediments affecting the adoption of smart contract applications within the sector.The study also delves into comprehensive measures to mitigate these barriers.In conclusion,this study critically evaluates the relevance of smart contract applications within the built environment,with a specific focus on promoting their usage.It may serve as a pioneering effort,especially within the context of Nigeria.

Influence law of multipoint vibration load on slope stability in Xiaolongtan open pit mine in Yunnan,China

The purpose of this work was to explore the influence law of vibration load on rock mass structure and slope stability.Based on the type and transmission way of vibration stress wave,the main stress in the horizontal and vertical directions was analyzed and the superposition effect of the stress wave was revealed.After the mechanical analysis of the sliding mass,the calculation formulas of the anti-sliding force and the sliding force were derived and the damage mechanism of blasting vibration to the structural plane was defined.In addition,according to the structure and lithologic parameter of the slope as well as the vibration monitoring data,the west slope stability of Xiaolongtan open pit mine was analyzed.The results show that the time-dependent stability factor is proportional to the vibration speed and the peak values appear at the same time.Vibration load promotes the breakage of the structural plane leading to the drop of the west slope stability factor by 0.23%.Under the multipoint simultaneous blasting,the fluctuating laws of the stability factors are consistent.The more the start-up points are,the higher the weakening degree to the slope stability is.Under the multipoint allochronic blasting,the stability factor depends on the synthetic waveform structure of all vibration waves.The greater the blasting time difference is,the lower the weakening degree to the slope stability is.Selecting the reasonable quantity of start-up points and time difference could fully reduce the adverse influence of vibration load to slope stability.

The pH of Cement-based Materials:A Review

Cement-based materials (CBMs),such as paste,mortar and concrete,are highly alkaline with an initial high pH of approximately 12.0 to 13.8.CBMs have a high pH due to the existing oxide mineral portlandite and alkali metal contents in Portland cement.The high pH of concrete provides excellent protection and reinforces the steel bars against corrosion.The pH of concrete does not remain constant due to ageing and other defect-causing factors,such as chloride ingress,alkali leaching,carbonation,corrosion,acid attack,moisture and biodegradation process.Reducing the concrete pH has negative impact on the strength,durability and service life of concrete buildings.However,the high pH of concrete may also cause concrete structure deterioration,such as alkali silica reaction,porosity and moisture related damages in concrete structures.The pH of CBMs can be influenced by high temperatures.For instance,the extremely high volume (85%-100%) of slag-blended cement pastes shows considerable pH reduction from 12.80 to 11.34 at 800 ℃.As many concrete structure deterioration are related to concrete pH,using an accurate and reliable method to measure pH and analyse the durability of reinforced concrete structure based on pH values is extremely important.This study is a comprehensive review of the pH of CBM in terms of measurement,limitations and varying values for different CBM types.

Variables Affecting the pH Measurement of Cement Mortars

A quantitative pH measuring method has been used to measure the pH of pure and blended cement mortars.The blended cement mortars incorporating supplementary cementitious materials(SCMs)such as fly ash(FA),ground granulated ballast furnace slag(GGBFS)and palm oil fuel ash(POFA)were used.Moreover,different variables affecting the pH values of CBMs such as temperature of sample solution,quantity of sample powder,dilution ratio and temporary storage of sample during pH measuring process have been studied for all cement mortars.

The dynamic stress intensity factor analysis of adhesively bonded material interface crack with damage under shear loading

This paper studies the dynamic stress intensity factor （DSIF） at the interface in an adhesive joint under shear loading. Material damage is considered. By introducing the dislocation density function and using the integral transform, the problem is reduced to algebraic equations and can be solved with the collocation dots method in the Laplace domain. Time response of DSIF is calculated with the inverse Laplace integral transform. The results show that the mode Ⅱ DSIF increases with the shear relaxation parameter, shear module and Poisson ratio, while decreases with the swell relaxation parameter. Damage shielding only occurs at the initial stage of crack propagation. The singular index of crack tip is -0.5 and independent on the material parameters, damage conditions of materials, and time. The oscillatory index is controlled by viscoelastic material parameters.

Computerised Development Control and Approval System for City Hall of Kuala Lumpur

This paper will discuss the computerised developm en t control and approval system being developed for the Planning and Development C ontrol Department, City Hall of Kuala Lumpur, with stress on the GIS architectur e developed within the system. The prospects and challenges towards implementati on of the system are also discussed.

Influencing factors on the accuracy of local geoid model

Different modification methods and software programs were developed to obtain accurate local geoid models in the past two decades.The quantitative effect of the main factors on the accuracy of local geoid modeling is still ambiguous and has not been clearly diagnosed yet.This study presents efforts to find the most influential factors on the accuracy of the local geoid model,as well as the amount of each factor’s effect quantitatively.The methodology covers extracting the quantitative characteristics of 16 articles regarding local geoid models of different countries.The Statistical Package of Social Sciences(SPSS)software formulated a strong multiple regression model of correlation coefficient r = 0.999 with a high significance coefficient of determination R^2 = 0.997 and adjusted R^2 = 0,98 for the required effective factors.Then,factor analysis is utilized to extract the dominant factors which include:accuracy of gravity data(40%),the density of gravity data(25%)(total gravity factors is 65%),the Digital Elevation Model(DEM)resolution(16%),the accuracy of GPS/leveling points(10%)and the area of the terrain of the country/state under the study(9%).These results of this study will assist in developing more accurate local geoid models.

Employing Green Roofs to Support Endangered Plant Species: The Eastern Suburbs Banksia Scrub in Australia

The purpose and context for the study relates to urban growth. Australian cities are experiencing particularly rapid urbanization, taking the form of land clearing to accommodate outward expansion as well as developing to higher densities in existing urban areas. Both forms of development degrade native biodiversity, resulting in loss of vegetation with the possibility that the remnant indigenous plants will become locally extinct. One endangered ecological community in Sydney, the Eastern Suburbs Banksia Scrub (ESBS), still survives along some sections of Sydney’s heavily urbanized coastline. At the time of European settlement, the ESBS covered approximately 5300 ha, but it is now a highly fragmented 146 ha across 24 sites with some sites under imminent threat of development. Conservation legislation enacted by the state of New South Wales (NSW), Australia has declared the ESBS as critically endangered. Despite recovery plans, in 2016 the NSW Threatened Species Scientific Committee indicated that the community faces an extremely high risk of extinction in Australia in the immediate future. A practical option in the face of declining open space in our cities is to examine the potential of urban rooftops for conserving and propagating threatened or endangered flora. While there is a limited amount of international research on using green roofs for endangered plant protection, there is no information from Australia about how green roofs perform in this geographic region. The approach taken in this research has been firstly, to review the current academic and “grey” literature from a global perspective to identify options for conserving endangered flora on green roofs. We derive an evidence-based research protocol to be used to test the green roof environment in Sydney for propagating the endangered ESBS. We establish the general applicability of green roofs for protecting vanishing flora through the literature review and conclude that our research design will be a suitable framework for the task for monitoring growth and germination performance over the ESBS community’s development cycle, with the longer-term objective of establishing a viable rooftop seed orchard.

Procurement Method Selection for Building Maintenance Projects: The Case of Malaysian Public Universities

The purpose of this paper is to implement and validate a decision making framework for building maintenance projects. The growing importance of maintenance sector not only in Malaysia but al- so increasingly globalized, the difficulty in selecting an appropriate procurement method and lack of research in this area provide an impetus for this research. There were 19 procurement selection criteria identified. In addition, there were 4 types of procurements methods which include outsourcing by specialist term contract, outsourcing by tendered schedule term contract, out- sourcing by repair and maintenance contract and outsourcing by measured term contract identified to be the most popular procurement methods adapted by public universities currently and at the same time were considered most important. The decision making framework was developed based on AHP technique and principles. Expert Choice Software was employed as development tool where the criteria and alternatives were integrated into the framework. Finally, structured interview was conducted to validate the framework developed. The validation process was carried out through structured interview with selected public university.

Optimizing the Global Digital Elevation Models(GDEMs) and accuracy of derived DEMs from GPS points for Iraq’s mountainous areas

Optimizing the combined horizontal and vertical accuracy of the well-known Global Digital Elevation Models(GDEMs) of various resolutions for each country and region especially in Iraq’s mountainous areas is still questionable. All the three GDEMs, approximately, have the same vertical accuracy with the Root Mean Square(RMSE) of ±7.3 m, ±7.6 m and ±6.5 m via 12 fixed Ground Control Points(GCPs) for the Advanced Land Observation Satellite Phased Array L-band Synthetic Aperture Radar(ALOS PALSAR 12.5 m), the Shuttle Radar Topographic Mission(SRTM 30 m) and the TerraSAR-X(the name of twin satellites) add-on for Digital Elevation Measurement(TanDEM-X 90 m) GDEMs respectively. Moreover, the percentage of outliers that are greater or smaller than ±10 m detection of the height extraction from both the ALOS PALSAR and SRTM Digital Elevation Models(DEMs) contains 16.7% and for TanDEM-X was 25%. In this paper,the special DEM is derived using 2123 handheld GPS points for Sulaymaniyah Governorate, Kurdistan region, Iraq. The height extraction by discarding the outliers of 58% gives the RMSE of ±8.0 m in the case of adding geoid heights(N) to the ellipsoidal heights(h) via the Earth Gravitational Model 2008(EGM2008)and ±5.6 m without adding N. It is expected that the derived DEMs will give more accurate results both horizontally and vertically in the mountainous areas when GPS observations are intensified. The horizontal accuracy is validated through extracting hierarchy stream types of the watershed map from the DEMs for higher than 100 pixels length. The ALOS PALSAR DEM extracted more numbers of stream orders than others.Finally, based on the criteria of RMSE, outlier detection, and the number of extracted stream orders, the ALOS PALSER DEM is regarded as the optimal GDEM in comparison with the close accuracy of both the TanDEM-X and SRTM DEM.

Preventive Maintenance Characteristics towards Optimal Maintenance Performance: A Case Study of Office Buildings

Lack of preventive measure is currently the problem that implicates poor building maintenance performance and issue on sustainability of buildings in Malaysia. Whereby, preventive maintenance is an effective approach to enhance the reliability and quality of a system and its components. This study seeks to investigate the characteristics of preventive maintenance towards the overall performance in building maintenance. Case study approach is adopted to identify the maintenance characteristics and aspects that lead to good performance. The research findings demonstrate that the most significant maintenance characteristics towards overall performance are skill and knowledge of maintenance labour, quality of spare parts and materials, length of predetermined maintenance interval, skill and knowledge of maintenance manager, capability to adopt maintenance equipment and technique, budget allocation for acquisition of maintenance data, reliability of maintenance data, as well as frequency of monitoring and inspection. As a conclusion, the significant maintenance characteristics must be taken into consideration to achieve optimal maintenance performance. In order to improve the effectiveness of maintenance strategy and the maintenance performance, the study recommends practice and provision of communication platform such as meeting and customer satisfaction survey that involves all the key participants from clients to customers.

Land Development on High Land Areas: Comparison of Process Implementation and Legislation Effectiveness between Malaysia and Hong Kong

The increasing of development failure on highland urges the professionals to develop solution on mitigating the problems. This paper discusses on land development process and legislation on highland development in Malaysia and Hong Kong. This study is focus on land use planning, laws and regulations pertaining to land development process. Hence, this research is to review the current development process including mechanism and legislation pertaining land development on highland in Malaysia and Hong Kong. Hong Kong is chosen as an example based on the fact that for its successfulness in managing highland developments. The main aim of this research is to evaluate the effectiveness of land development legislations and development approaches for highland development. This research reveals the effects and consequences of implementation regulations and development process on highland that have been used at Malaysia and Hong Kong. In Malaysia, land development process on highland is still in questionable;why present property laws and regulations are fail to achieve highland development standards as compared to Hong Kong. There are weaknesses that need to be overcome such as on the implementation and the intensity of the provision in property laws and regulation that can ensure the achievement of required land development process.

Examining the Impact of Welfare Facilities on Building Construction Employee’s Performance in the Eastern Region of Ghana

Building Construction employees essentially required sufficient welfare facilities such as a place for washing, shower, change over, eat and drink, a place to store and hang clothing. Yet, these fundamental necessities are regularly disregarded. Decent welfare facilities can absolutely promote health and well-being and can aid to avert contracting diseases at building construction site. The aim of this study is to examine the impact of welfare facilities on building construction workers performance in the Eastern Region Ghana. The objectives were to identify welfare facilities provided by building construction firms, evaluate the satisfaction level of building construction firms’ employees with welfare facilities in Eastern Region, and determine the relationship between provision of welfare facilities and employee’s performance. The study employed convenient sample to investigate 80 building construction employees through questionnaires administration. Data generated from the survey was further analyzed using SPSS, weighted mean formula was used to determine the mean ranking, and descriptive and inferential statistics such as mean score, percentages, frequencies and chi square were used. The study reveals that the extent of welfare facilities at various construction sites was almost unavailability of sanitary and toilet facilities, unavailability of washing facilities, and unavailability of changing room, whiles drinking water and locker facilities were available but not sufficient. The study further finds that construction employees are dissatisfied with the condition of welfare facilities provided at their various work places. The study finally concludes that if workers are provided with decent welfare facilities at various building construction sites, it will motivate them to improve performance. The study recommends that metropolitan, municipal and district authority (MMDAs) should set a task force to check the implementation of welfare facilities at construction site as the results are pointing woeful insufficiency of welfare facilities at Eastern Region construction firms in Ghana.

Water in Architecture, Architecture of Water

Water is one of the fundamental resources for the survival of humanity and during the centuries in all the world it became integral part of building and garden architecture. For this reason, starting from general considerations of our countries of origin, we wanted to collect in this article some of the most representative examples of water treatment all over the world in three different fields: the outdoor spaces, the indoor spaces and the in-between spaces, both public and private, to mark the role of water in the designing of architectural process in the last 25 years and proposals for the future not so far.

Planning Strategic Sustainable Development in Malaysia by Incorporating the Concept of Low Carbon Society

Malaysia has undergone rapid urbanization and economic growth for past decades and is expected to continue to have an average economic grow at 5%-6% per annum in the next five years. This phenomenon of growth and pursuit of socio-economic progress has great impact not only on the economy but also on community life style and environment. The concept of sustainable development was adopted by Malaysia government as early as mid 1990s to address some of the emerging environmental issues and more specifically on climate change issues recently. Malaysia government announced a commitment of voluntary 40% reduction in CO2 emission intensity by 2020 during the Conference of Party （COP15） meeting in Copenhagen in 2009. In parallel to this commitment of CO2 emission reduction, the concept of sustainable development in urban planning should incorporate a more comprehensive and quantitative approach in the preparation of development plan as well as in exercising the routine development control practice at the local planning authority. This paper prepares a quantitative scenario study on the establishment of low carbon society in Iskandar Malaysia.

Professional Education of Quantity Surveyors for the Indonesian Construction Industry

Education and Job Training is defined as informal education in the laws of the Republic of Indonesia concerning the National Educational System in Article 26 Point 3. Education and Job Training is carried out for individuals who require knowledge, work skills, life skills, and the correct attitudes for self-development, professional development, work, independent business and continued education. In the Indonesian construction industry, the Quantity Surveyor is a common role in planning and controlling consultant firms. These firms are organized as members of National Association of Indonesian Consultants. Many firms employ architects and technical staff as Quantity Surveyors, even if they only have experience in project calculations. This has given rise to the problem of inaccurate cost projections in the construction industry. Therefore, the future of Quantity Surveyors in Indonesia hinges on the implementation of education and short courses as means of raising the skill level of the profession. These steps will help to bridge the knowledge gap between local and foreign consultants.

Structural Performance of Prefabricated Timber-Concrete Composite Floor Constructed Using Open Web Truss Joist Made of LVL Paraserianthes Falctaria

This paper investigates an open web truss joist (OWTJ) made of laminated veneer lumber (LVL) Paraserianthes falctaria as a prefabricated timber-concrete composite floor system. The four-point bending test showed that structural performances of the OWTJ, conventional composite floor (CCF), and prefabricated composite floor (PCF) were similar. Although composite action was not developed as no lateral deformation was observed at the shear connectors, installing a concrete slab above the OWTJ can slightly increase the ductility factor of the composite floor. Furthermore, a finite element model was developed, and the model proved to be suitable for simulating the structural performance of the composite floor.

Systematic review of the efficacy of data-driven urban building energy models during extreme heat in cities:Current trends and future outlook

Energy demand fluctuations due to low probability high impact(LPHI)micro-climatic events such as urban heat island effect(UHI)and heatwaves,pose significant challenges for urban infrastructure,particularly within urban built-clusters.Mapping short term load forecasting(STLF)of buildings in urban micro-climatic setting(UMS)is obscured by the complex interplay of surrounding morphology,micro-climate and inter-building energy dynamics.Conventional urban building energy modelling(UBEM)approaches to provide quantitative insights about building energy consumption often neglect the synergistic impacts of micro-climate and urban morphology in short temporal scale.Reduced order modelling,unavailability of rich urban datasets such as building key performance indicators for building archetypes-characterization,limit the inter-building energy dynamics consideration into UBEMs.In addition,mismatch of resolutions of spatio-temporal datasets(meso to micro scale transition),LPHI events extent prediction around UMS as well as its accurate quantitative inclusion in UBEM input organization step pose another degree of limitations.This review aims to direct attention towards an integrated-UBEM(i-UBEM)framework to capture the building load fluctuation over multi-scale spatio–temporal scenario.It highlights usage of emerging data-driven hybrid approaches,after systematically analysing developments and limitations of recent physical,data-driven artificial intelligence and machine learning(AI-ML)based modelling approaches.It also discusses the potential integration of google earth engine(GEE)-cloud computing platform in UBEM input organization step to(i)map the land surface temperature(LST)data(quantitative attribute implying LPHI event occurrence),(ii)manage and pre-process high-resolution spatio-temporal UBEM input-datasets.Further the potential of digital twin,central structed data models to integrate along UBEM workflow to reduce uncertainties related to building archetype characterizations is explored.It has also found that a trade-off between high-fidelity baseline simulation models and computationally efficient platform support or co-simulation platform integration is essential to capture LPHI induced inter-building energy dynamics.