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Many countries have started to use post-tensioned (PT) concrete because of its sustainability and low cost. However, it is not quite popular in Sri Lanka as the required knowhow and technology are not available within the country. By introducing PT concrete to the country, unwanted costs and time overruns could be eliminated from the construction projects. This paper, therefore, aims to identify the suitability and acceptability of PT concreting for/in Sri Lanka.

An extensive literature review was first carried out to gather knowledge on PT concreting. The four case studies that followed it included eight semi-structured interviews and a document review. Ten expert interviews were conducted finally to strengthen the findings of the literature review and case studies. Cross-case analysis and NVivo 11 content analysis software were used to analyze the data gathered.

Findings reveal that PT concreting saves cost and time of construction and that it can have a control over the resources required for construction, which makes it environment-friendly. PT concreting allows thinner concrete sections, extended spans, stiffer walls that resist lateral loads and stiffer foundations that resist the effects of shrinking and swelling soils.

It is found that PT concreting is more suitable for the construction industry in Sri Lanka than traditional concreting.

Engineered stone is a material which can be described as an artificial stone. The exemplary application area is sink production. There are very few research projects about this type of material. In fact, most of them are research conducted by the manufacturing company, which are limited to the basic properties of the material. However, knowledge about fracture mechanic of this material may be crucial in terms of usage. The paper aims to discuss this issue.

Analysis of the inside structure was made using an optical microscope as well as SEM. In the paper, methods which can be used to obtain data about fracture behaviour of material are presented. Using eXtended Finite Element Method and experimental data from three-point bending of notched specimens stress intensity factors (SIFs) for I and II load modes were obtained. Finally, a comparison between the fracture initiation angle in the function of the ration of SIFs for I/II load modes and maximum tangential stress hypothesis prediction was presented.

Analysis of the inside structure proves that this type of material has an uneven distribution of particle size. This can follow to void and micronotches formation and, later, to the failure of the material. A method of obtaining stress intensity factors for the discussed type of material and specimens can be successfully applied to other similar material, as proposed in this work. Standard crack angle propagation criteria are not sufficient for this type of material.

There are very few research papers about this type of material. The subject of fracture mechanic is not properly discovered, despite the fact that IT is important in terms of the application area of these materials.

This note comes from the Building Conservation Trust and is based on a statement issued by the Trust's Technical Committee. The Trust operates the permanent exhibition which is open daily at Hampton Court Palace, East Molesey, Surrey KT8 9BS.

The purpose of this paper is to present a method for evaluating the structural dynamic characteristics of a flying probe tester.

The dynamic characteristics of a flying probe tester framework were analyzed based on a finite element analysis method. First, modal analysis was carried out to characterize the modal parameters of the structure. Second, the harmonic response was analyzed according to the modal analysis and the response curve of the structural system was studied. Finally, transient analysis was conducted to obtain the transient response of the structures at the beginning of the vibration.

The natural frequency and the response frequency of a natural granite structure was the highest and the transient vibration displacement amplitude was the smallest compared with cast iron and artificial stone structures.

A comprehensive understanding of the dynamic characteristics of the framework of a flying probe tester with three different materials has been achieved. The results of the analyses provide a reference for the framework design of a flying probe tester.

Some historic observations With the exception of our prehistoric and primitive stone built ‘homes’ such as Chysauster and Cam Euny hut circles in Cornwall, the cromlechs, dolmens and stone circles at Avebury and Stonehenge, it was the Romans who introduced fine and sturdy stone construction into our country. The Anglo‐Saxons left many fragments of their crudely dressed stone towers and chancels of their churches, which have survived due to their robust construction. The timber construction of the Dark Ages gave way to stone again and to the gradual establishment of the craft of the stonemason.

This paper aims to clarify the notion of artificial intelligence (AI), reviewing the present scope of the phenomenon through its main applications. It aims at describing the various applications while assessing the markets, highlighting some of the leading industrial sectors in the field. Therefore, it identifies pioneering companies and the geographical distribution of AI companies.

The paper builds upon an in-depth investigation of public initiatives focusing mostly on the EU. It is based on desk research, a comprehensive review of the main grey and scientific literature in this field.

The paper notes that there is no real consensus on any definition for this umbrella term, that the definition does fluctuate over time but highlights some of the main changes and advances that took place over the past 60 years. It stresses that, in spite of the hype, on both the business and consumer sides, the demand appears uncertain. The scope of the announced disruptions is not easy to assess, technological innovation associated with AI may be modest or take some time to be fully deployed. However, some companies and regions are leading already in the field.

The paper, based on desk research, does not consider any expert opinions. Besides, the scientific literature on the phenomenon is still scarce (but not the technical one in the specific research sectors of AI). Most of the data come from consultancies or government publications which may introduce some bias, although the paper gathered various, often conflicting viewpoints.

The paper gives a thorough review of the available literature (consultancies, governments) stressing the limitations of the available research on economic and social aspects. It aims at providing a comprehensive overview of the major trends in the field. It gives a global overview of companies and regions.

This seventh article in the “Small urban spaces” series deals with the “hardware” of squares and similar enclosures including statues, seating and bollards. Railing and pavings have been covered in earlier articles.

A new artificial intelligence (AI) project in Israel. A national centre for artificial intelligence, which covers the fields of computer science, neurosciences and psychology, has been founded at the Weizmann Institute at Rehovot in Israel. The research team hopes to understand some of the facets of the human thought process and apply their results to the creation of machines which “can learn from experience”, “understand and speak a natural language”, and “assess situations”. The aim is to produce a machine with “Common sense”. Initially work will be carried out in vision capabilities (Professor Ullman), and the development of hardware and language for parallel processing. The institute will also conduct research into advanced robotics (Dr Flash) with a particular interest in manipulator kinematics and dynamics as well as trajectory planning.

Outlines the development of English brickwork from 1485 to 1914, highlighting the many external influences that were underpinning the styles and practices of the various periods, such as developments in materials, craft skills and practices, and the change in architecture.

Second part of a perspective of the development of the English brick and its use since the 15th century. Evaluates the many varying external influences such as trade links, architectural fashions, industrial developments and social factors that were invariably under‐pinning the styles and practices of the brickmaker and bricklayer down the centuries. Analyses this history in a series of chronological periods, i.e. 1485‐1603; 1603‐1830 and 1830‐1914. The pattern of study remaining consistent within each period, that being – what was the significant socio‐economic and political movement in relation to construction, and what, if any, part did it play in influencing change in the making and use of bricks. Looks at how and why brick manufacture and brickwork were responding, and when within these periods, considering who were the important figures in these changes and developments. Concludes that the brickwork, which marks each period, is the result not only of developments in the brickmaking process and the craft skills of the bricklayers, but also of foreign influences, social and economic changes in the country, and the inevitable gradual influence of building control, through legislation, necessary to ensure safe and sanitary housing in the urban environment of a major industrial country.