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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.

Outlines the most common causes of movements in masonry buildings, how they should be avoided by design measures and, if cracking has occurred, how the cause may be identified. Discusses moisture movements in materials, temperature changes, strains resulting from applied loads, foundation movements and chemical reactions in materials. Examines methods of accommodating movement and the assessment of damage. Suggests the structure of an examination undertaken by a surveyor on discovering masonry cracks.

Reviews the history of the development of cavity wall ties, particularly in relation to their durability, and covers recent improvements in both materials specifications and performance. Describes newer forms of tie and illustrates those suitable for fixing new masonry to timber, concrete, steel and lightweight concrete slabs or blockwork as well as alternatives to the traditional tie types. Discusses products installed in existing walls to deal with problems such as corrosion of original ties, insufficient provision, or ties of the wrong specification.

The use of clay brickwork masonry as a cladding on framed building structures is reviewed and the problems with the modern form of construction for brickwork cladding highlighted. The potential for developing simpler, improved forms of cladding, in which free vertical movement of the brickwork is restrained, is discussed. Preliminary results are presented of an ongoing programme of research to investigate the performance of clay brickwork under conditions of vertical restraint, involving the construction and monitoring of full‐scale brickwork test panels on a multi‐storey concrete frame.

The purpose of the study is to analyse the feasibility of using the potential and exponential curve models to assess the learning of a group of welders, when welding stainless steel piping with the tungsten inert gas process.

The welding productivity data grouped according to the requirements of the ASME SECTION IX code is organised into two groups: average productivity and baseline productivity. When processing the adjustment to the two models, the Excel software Solver tool was used. The criteria for assessing the quality of the fit were: least squared method, Spearman's correlation coefficient and graphical method. The impact of the variation coefficient on the average productivity and the amplitude (difference between the minimum and maximum productivity) was also evaluated on the baseline productivity.

The curves elaborated based on the average productivity presented better quality of adjustment than those constructed from the baseline productivity. The potential and exponential models presented similar adjustment conditions, with the second having a slightly superior performance. There were no productivity gains due to learning in the studied time interval. The grouping of the average daily productivity data based on the diameter range established in the ASME code section IX presented satisfactory results, enabling its use by the industry.

There is no news of work on piping welding with this focus. The proposal to group the productivity data according to the degree of difficulty of execution established by the ASME code section IX, widely used in the industry, is a significant contribution to monitoring the evolution of learning. In the same way, the results allow to adopt the average productivity determined from the first 20 days of realisation of a project, as a reasonable indicator to estimate the future performance of the work, helping to correct deadlines during the realisation of a project.

Brickwork has been around for some 4,000 years and its durability, strength and other good qualities are well known. It is a useful structural material — but limited to applications where there is relatively high compressive vertical loading and relatively low horizontal loading. (A brick wall can carry a high vertical load but it can be pushed over relatively easily.) This is because brickwork, like concrete, is weak in tension. Its tensile strength in bending is less than five per cent of its compressive strength. Again, like concrete, it can either be reinforced with steel to carry the tensile stress or prestressed to eliminate the tension.

The purpose of this paper is to present information on the construction technology used to build Dublin City Council’s (DCC’s) housing stock, with an emphasis on wall construction.

The methodology applied was a mix of literature review and archival research. The research was undertaken as part of PhD research exploring the energy upgrade of a housing stock.

The research uncovered details of the construction technology used in the construction of DCC’s housing stock, especially wall construction. These details disprove perceptions and assumptions made on the evolution of construction technology in Dublin and Ireland.

The research is limited in that it primarily focused on the period between 1887 to the introduction of the 1991 Building Regulations. Further research is required on both DCC’s housing stock and the Irish housing stock to identify the specific changes in construction technology.

It is hoped this research will be a foundation for further research on the evolution of house construction technology, and housing stock asset intelligence in Ireland.

This research provides information for researchers and professionals with an interest in the evolution of Irish house construction technology. This is an area which has not received significant attention in Irish built-environment research.

The purpose of this paper is to describe the development of a risk assessment model to assess the occupational safety and health (OSH) risks presented by different construction approaches, namely traditional and industrialised building system (IBS). The development process applies the concept of argumentation theory, which helps construction designers integrate the management of OSH risk into the design process. In addition, an energy damage model is used as an underpinning framework for developing the model.

Development of the model was achieved through two phases. Phase I involved collection of data on the activities involved in the construction process and their associated OSH risks, derived from five different case studies, field observation and interviews. Knowledge of design aspects that have the potential to impact on OSH was obtained from document analysis. Using the knowledge obtained in phase I, a model was developed in the form of argument trees (Phase II), which represent a reasoning template with regard to options available to designers when they make judgements about aspects of their designs. Inferences from these aspects eventually determined the magnitude of the damaging energies for every activity involved. Finally, the model was validated by panels of experts, and revisions and amendments were made to the model accordingly.

The risk assessment model development revealed that the concept of argumentation theory and energy damage model is suitable to represent design safety risk knowledge and effectively address the designer's role in making decisions in their designs and further illuminate the level of OSH risk their designs pose.

The developed model provides best-practice reasoning support for construction designers, which help them to understand the impact of their designs decisions on worker's safety and health, and thereby assist them to further mitigate the risk to an acceptable level.

This study departs from the existing tool in that the model was developed based upon the combination of argumentation theory and energy damage model. The significance of the model is discussed.

Examines a research program into the use of automation and robotics in masonry building. The four main objectives of the project were to establish the requirements for the application of robotics in masonry construction; construct a prototype robot; develop the operation software system; and evaluate suitable blocks for construction using robots. Describes the construction of the prototype robot cell and the research methods used and concludes that combining the research findings with work elsewhere it should be possible to achieve a commercially viable robotic solution for masonry and similar tasks on the construction site.

Capillary rise of water in buildings has been an issue of concern among past and present researchers. Despite the research efforts devoted to the proper elimination of the problem in masonry construction, it still remains a challenge that needs to be addressed. The purpose of this paper is to explore treatment mechanisms that can be used to prevent rising damp in new building infrastructure.

In total, 14 test walls are constructed, conditioned, subjected to various treatments and monitored for four years. The treatments applied to the walls include the use of polyethylene damp proof courses, damp proof coatings and dense concrete bases. The walls are then monitored with reference to the two climate seasons in Ghana.

The results highlight that rising damp is present, as suggested by the constant increase and decrease in the height of the water levels in the walls during the rainy and dry seasons, respectively. The findings further reveal that within the four-year period, the walls treated with the damp proof coatings, together with those with the dense concrete bases performed better than those treated with the polyethylene damp proof courses.

The economic and commercial impact of these preventive mechanisms were not considered in this study. A future research can be directed at these issues.

The proposed treatment mechanisms highlight the effectiveness of some treatments applied to walls to prevent the capillary rise of water from the ground into the superstructure.

Building regulations, especially in Ghana and other tropical settings should be amended to include ways to prevent rising damp phenomena by including effective methods against rising damp during the building design or construction.

Series of studies worldwide have been conducted in laboratories to simulate the capillary rise of water in walls of buildings. This is among the few studies that look at how water rises from actual ground conditions into the walls of buildings.