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Timely removal of formwork is one of the crucial aspects of construction management that directly influences the safety and quality of the structure as well as the economy of the project. Code recommendations in this regard are not widely practiced because of the difficulties in their implementations. Also, such code recommendations are not robust for all the possible construction conditions. The present paper proposes an IoT-enabled system that notifies the minimum striking time of vertical formwork based on a specified target compressive strength.

An IoT device is proposed for the timely removal of vertical formwork by monitoring of early age concrete compressive strength in real-time. The maturity method is utilized for this purpose. The implementation of the proposed system is demonstrated on three concrete columns. The proposed system is found to be suitable for any construction condition.

The proposed system is a novel, cost-effective, IoT-enabled real-time monitoring system which includes features like cloud connectivity and remote monitoring. This system can be easily implemented at the site without any human intervention.

The study explores the development of an IoT device for the timely removal of vertical formwork which will ensure quality, safety and productivity in concrete construction.

This paper is the first attempt to determine the minimum striking time of vertical formwork using IoT-based technology.

This study aims at introducing a method based on the failure mode, effects and criticality analysis (FMECA) to aid in selecting the most suitable formwork system with the minimum overall cost.

The research includes a review of the literature around formwork selection and analysis of data collected from the building construction industry to understand material failure modes. An FMECA-based model that estimates the total cost of a formwork system is developed by conducting a two-phased semi-structured interview and regression and statistical analyses. The model comprises material, manpower and failure mode costs. A case study of fifteen buildings is analysed using data collected from construction projects in the UAE to validate the model.

Results obtained indicate an average accuracy of 89% in predicting the total formwork cost using the proposed method. Moreover, results show that the costs incurred by failure modes account for 11% of the total cost on average.

The analysis is limited to direct costs and costs associated with risks; other costs and risk factors are excluded. The proposed framework serves as a guide to construction project managers to enhance decision-making by addressing the indirect cost of failure modes.

The research proposes a novel formwork system selection method that improves upon the subjective conventional selection process by incorporating the risks and uncertainties associated with the failure modes of formwork systems into the decision-making process.

Tight schedules in high-rise building construction force project managers to use the formwork even in a bad weather condition. Insufficient craning, which is typically the bottleneck in construction activities, and lack of space in confined sites make it hard to install the formwork on the ground. The Automatic Climbing System (ACS), a type of jump forms, solves these problems enabling the formwork to climb in various weather and height conditions. The aim of this paper is to discuss these issues.

Current research focusses on the ACS, its application, and productivity assessment. Productivity and construction data are collected from a specialized company in such type of forms. A bracket productivity model has been developed to estimate floor construction cycle time and productivity.

Results show that average productivity is four days/floor. The developed model is validated, which shows robust results 97.80 percent.

The implementation of the developed models are limited to only two projects. However, the developed models and framework is sound for future improvement.

The developed methodology and model play essential roles in decision-making process.

The developed methodology and model are beneficial to researchers, practitioners, and planners of construction projects. It provides practitioners with charts that assist in scheduling and managing resources for jump form application. In addition, it provides researchers with a floor cycle time model and framework of implementing jump forms to high-rise buildings.

The objective of this paper is to investigate the effects and relative influence of: grid patterns; variability of foundation sizes; total surface area; and average surface area, on formwork labour productivity of isolated foundations.

To achieve this objective, a sufficiently large volume of productivity data were collected and analyzed at both levels; macro, and micro, using the linear regression method. As a result, the effects and relative influence of the investigated factors on formwork labour productivity are determined and quantified.

The findings show significant impacts of the buildability factors investigated on formwork labour productivity, and substantiate the importance of applying the rationalization and standardization concepts to the design stage of construction projects.

Further research into the effects of buildability factors on formwork, and other related trades of in situ reinforced concrete material, i.e. rebar fixing/installation and concreting, labour productivity, which are common to other structural elements and activities such as, grade/ground beams, columns, walls, beams, and slabs, is recommended, so that the related findings can ultimately be used to develop an automated “Buildability Design Support System” to formalize the buildability knowledge of reinforced concrete construction projects.

The outcomes of this research provide designers with feedback on how well their designs consider the requirements of buildability principles, and the tangible consequences of their decisions on labour productivity. In addition, practical recommendations deduced from the findings are presented, which upon implementation, can improve the buildability level of this activity, hence translate into higher labour efficiency and lower labour costs. On the other hand, the depicted patterns may provide guidance to construction managers for effective activity planning and efficient labour utilization.

The findings fill a gap in buildability knowledge and its influence on formwork labour productivity of an important, labour intensive, activity within the in situ reinforced concrete construction projects.

Due to a dearth of quantitative research into buildability factors affecting formwork labour productivity of in situ reinforced concrete construction, the purpose of this paper is to establish a distinct point of departure from the prevalent qualitative trend of buildability research practices by exploring, quantifying and comparing the influence of the two widely used design schemes; namely, beamless and beam-supported building floors, on formwork labour productivity.

A considerable quantity of relevant formwork labour productivity data associated with each building floor configuration was collected from projects sharing similar characteristics. The data were analysed to determine the statistical significance of the difference between the two labour productivity “means” of the sample sets representing both populations. Regression analyses were further carried out to assess the impact of floor area on labour efficiency.

The results obtained show a statistically significant difference between the two means of formwork labour productivity achieved, where the efficiency of “forming” the beam-supported floor type is, on average, lower by 57 per cent than that of the beamless configuration. The outcomes further demonstrate a significant influence of building floor area on the productivity of the form-working operation.

The findings can provide designers with feedback on how well their decisions consider the requirements of buildability principles, and the consequences thereto on labour productivity. The depicted pattern of results may, moreover, provide guidance to estimators and project managers for reasonable cost estimation, effective planning and efficient labour utilisation.

The general guidelines available for buildability improvement lack the supporting quantitative evidence, and thus are often viewed with scepticism, especially amongst design practitioners. On the contrary, the quantitative outcomes reported in this study are based on rigorous methodology, hence can be used as a supporting reference to “formalise” the specific buildability knowledge of the activity explored.

Hong Kong is running out of both reclamation sites and landfill space for the disposal of construction and demolition waste. This paper reports on the findings of a study, consisting of a questionnaire survey, interviews and work‐site visits, to compare the use of low‐waste building technologies in public housing and private residential projects in Hong Kong. The results show that large panel formwork and prefabricated building components are widely used in public housing projects in Hong Kong. Due to the difference of the design with public housing, the use of smaller aluminium panel formwork is more common in the private housing projects. The barriers for the adoption of low‐waste building technologies in the private sector are identified and discussed.

Damage to reinforced concrete (RC) structural elements is inevitable. Such damage can be the result of several factors, including aggressive environmental conditions, overloading, inadequate design, poor work execution, fire, storm, earthquakes etc. Therefore, repairing and strengthening is one way to improve damaged structures, so that they can be reutilized. In this research, the use of an ultra high-performance fibre-reinforced concrete (UHPFRC) layer is proposed as a strengthening material to rehabilitate damaged-RC beams. Different strengthening schemes pertaining to the structural performance of the retrofitted RC beams due to the flexural load were investigated.

A total of 13 normal RC beams were prepared. All the beams were subjected to a four-point flexural test. One beam was selected as the control beam and tested to failure, whereas the remaining beams were tested under a load of up to 50% of the ultimate load capacity of the control beam. The damaged beams were then strengthened using a UHPFRC layer with two different schemes; strip-shape and U-shape schemes, before all the beams were tested to failure.

Based on the test results, the control beam and all strengthened beams failed in the flexural mode. Compared to the control beam, the damaged-RC beams strengthened using the strip-shape scheme provided an increase in the ultimate load capacity ranging from 14.50% to 43.48% (or an increase of 1.1450 to 1.4348 times), whereas for the U-shape scheme beams ranged from 48.70% to 149.37% (or an increase of 1.4870–2.4937 times). The U-shape scheme was more effective in rehabilitating the damaged-RC beams. The UHPFRC mixtures are workable, as well easy to place and cast into the formworks. Furthermore, the damaged-RC beams strengthened using strip-shape scheme and U-shape scheme generated ductility factors of greater than 4 and 3, respectively. According to Eurocode8, these values are suitable for seismically active regions. Therefore, the strengthened damaged-RC beams under this study can quite feasibly be used in such regions.

Observations of crack patterns were not accompanied by measurements of crack widths due to the unavailability of a microcrack meter in the laboratory. The cost of the strengthening system application were not evaluated in this study, so the users should consider wisely related to the application of this method on the constructions.

Rehabilitation of the damaged-RC beams exhibited an adequate structural performance, where all strengthened RC beams fail in the flexural mode, as well as having increment in the failure load capacity and ductility. So, the used strengthening system in this study can be applied for the building construction in the seismic regions.

Aside from equipment, application of this strengthening system need also the labours.

The use of sand blasting on the surfaces of the damaged-RC beams, as well as the application of UHPFRC layers of different thicknesses and shapes to strengthen the damaged-RC beams, provides a novel innovation in the strengthening of damaged-RC beams, which can be applicable to either bridge or building constructions.

MORE than thirty national bodies, previously comparative strangers, have been brought into closer contact during the year. They have now collectively organised a National Productivity Year Conference to be held at Eastbourne in the closing days of November. It would be wrong to regard this as a finale; to apply to it the closing words of Vanity Fair: ‘Come, children, let us shut up the box and the puppets, for our play is played out.’

The applicability of learning curve theory to the construction industry has been investigated by several studies; however, the outcomes are characterised by inconsistent, rather sporadic patterns. Therefore, the purpose of this paper is to explore the effect of learning on concrete masonry blockwork labour productivity in recurring building floor cycles.

Repetitive blockwork labour inputs from 52 multi-storey residential buildings were collected and analysed using the straight-line learning curve model. The cumulative average labour input for each recurring floor and its corresponding cycle number were modelled using the least squares method.

According to the learning curve theory principles, labour inputs are expected to decrease by a certain percentage as the floor cycle number within each building observed increases. Nonetheless, the patterns emerged from this study provide little evidence for that.

Contrary to several previous findings which have asserted the significance of the learning concept to construction productivity, the results obtained for the activity investigated suggest that there is no potential context for the theory to be used as a useful tool to quantify productivity improvement, or to provide for a practical project management observation and control system.

Notwithstanding the numerous research into the effect of learning on construction activities, this study is unprecedented in examining the applicability of the theory to concrete masonry blockwork labour productivity in building construction. It can thus assist in achieving reliable planning, determining the plausibility of correlating past performances or predicting future expenditures, and appraising the potentiality of the learning phenomenon as a useful tool to quantify productivity improvement over the repetitive cycle process of such a distinct construction activity.

A popular façade treatment for buildings in Hong Kong is tile cladding. It is used for the majority of low and high‐rise residential buildings and the less expensive office developments in lower grade business districts. Mosaic and ceramic tiles are generally durable, versatile, waterproof and need little maintenance. However, tile defects such as dislodgement and water penetration can affect buildings that are only a few years old. The paper examines the typical causes of tiling defects and the range of repair methods that are being adopted in Hong Kong.