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This study aims to determine the effect of replacing a portion of the cement in the concrete mixture with silica fume (SF) on the corrosion resistance of reinforcing bars, the compressive strength of concrete and the tensile strength of hook bars in both corroded and non-corroded external joints of structures. The external beam-column connection was studied because of its critical role in maintaining structural continuity in all three directions and providing resistance to rotation.

In external concrete joints, the bars at the end of the beams are often bent at 90° to form hooks that embed in columns. Owing to the importance of embedding distance and the need to understand its susceptibility to corrosion damage from chloride attack, a series of experiments were conducted on 12 specimens that accurately simulate real-site conditions in terms of dimensions, reinforcement and hook bars. SF was replaced with 10% and 15% of the weight of cement in the concrete mixture. To simulate corrosion, the specimens were subjected to accelerated corrosion in the laboratory by applying a low continuous current of 0.35 mA for 58 days.

The results revealed the effect of SF in improving the compressive strength of concrete, the pullout resistance of the hook bars and the corrosion resistance. In addition, it showed an apparent effect of the corrosion of reinforcing bars in reducing the bonding strength of hook bars with concrete and the effect of SF in improving this strength.

It was noted that the improvement of the results, achieved by replacing 10% of the weight of cement with SF, was significantly close to the results obtained by replacing 15% of the SF. It is recommended that an SF ratio of 10% be adopted to achieve the greatest economic savings.

To solve the reinforcement congestion, mechanical anchorage is increasingly popular in use instead of conventional hook rebar. However, the bond performance between the rebar and concrete and the range of stress transfer between the two are still not well understood. The purpose of this study is to study the bond performance and failure mechanisms between reinforcement and concrete around an anchorage zone in a structural element.

In this study, simulations were carried out by 3D RBSM (Rigid Body Spring Model). This approach divided a problem of interest into elements, namely concrete and steel elements. And to simulate the failure of anchorage of RC, the steel element size is set according to the geometry complexity of the reinforcing bar. By using this method, two simulation cases of anchorage failure were carried out.

This paper shows that simulations demonstrated good agreement with experimental data in terms of anchorage capacity, crack pattern, and failure mode. This indicates that RBSM analysis can simulate the failure behavior governed by complex cracks.

This paper indicates the analytical approach to investigate the anchorage performance of RC.

January 27, 1970 Mines Quarry — Dangerous machinery — Moveable bar on tractor — Four‐inch nip when bar fully raised — Tractor being removed from pit by attaching dragline to bar — Slip by employee trapping foot in nip — Whether a “dangerous” exposed part of machinery — Whether duty to fence — Dragline not long enough to reach if tractor on level ground — Tractor backed short way up slope of pit — Whether failure to provide longer dragline breach of statutory or common law duty — Mines and Quarries Act, 1954 (2 & 3 Eliz.II, c.70), ss. 82(1), 115.

One of the common law duties owed by the employer is his duty to take reasonable care for the safety of his employee. This common law duty is an implied term in the contract of employment and is therefore contractual in nature. Because of the difficulties which may arise in bringing an action in contract for breach of the employer's duty of care, the employee who has sustained injuries during the course of his employment (although he may sue either in contract of tort will normally bring a tort action.

WHEN John I. Snyder Jr. flew over from the United States he probably did not relish the Cassandra rôle into which circumstances had forced him. As president of U.S. Industries he gave one of the most depressing addresses of modern times. Since his firm is a large manufacturer of automation machines it was probably natural that he should say: ‘Automation is inevitable. Its use is rapidly increasing. Positive action by the makers of automation machines must be taken now to preserve the human values which could otherwise become cannon fodder of the automation barrage.’

The job of ding man is very highly skilled: it contains a large number of advanced sensori‐motor skills and much decision‐making. For many years different car‐builders have wrestled with the training of this key worker, for a long time without success. Ray Basey, Skills Analyst at Fords, Dagenham, has studied this job in depth and developed highly effective training in it. His article is a study in how to approach the business of training for complex manual skills.

With an annual cost of gold exceeding 10 million dollars for its captive circuit board shop, Tektronix, Inc., established a task force to implement conservation. Elements included Purchasing, Material Control, Quality Assurance, Manufacturing and Engineering. Salient programme items were inventory reduction, material accountability, modification of processes, procedures, and equipment to improve uniformity of thickness, and elimination of non‐essential gold use. In addition, scrap‐handling procedures were modified to improve accountability and reclaim returns.

An interesting electrochemical process for de‐rusting corroded equipment and plant has been operated with increasing success since the war by the London firm of Derustit (Great Britain) Limited. The process removes rust and other surface deposits and completely cleans the machinery or parts treated but does not render the surface corrosion‐resistant. Essentially, therefore, it is a metal cleaning and pre‐treatment process. It can be and has been applied to rusted machinery ranging from ball‐bearings to large locomotive parts, and many large firms and all the Service departments have made use of this means of metal ‘laundering.’

The purpose of this mixed methods rapid study was to identify the barriers and facilitators to implement relational and environmental risk management approaches to manage suicidality in inpatient services.

To achieve this within a short timeframe, a rapid review approach was chosen. Both research (qualitative and quantitative studies) and non-research material (policies, guidance and reports) were retrieved. The review was conducted across five databases: MEDLINE, EMBASE, EMCARE, PsycINFO and CINAHL for English language citations within the last ten years (2009 –2019).

A total of 17 primary research papers and a further 73 reviews and grey literature were included. There was evidence that the removal of anti-ligature equipment, by which regular checks of the environment to identify and remove ligature points and increased levels of observation are carried out well, reduces suicide in hospital.

There is a gap in research investigating “engagement activities” eliciting exactly what they are and determining how they might be effective. There is a need for new innovative ways for managing risk of suicide in hospitals that bring together meaningful engagement and maintaining safety.

Keeping people safe during an inpatient stay in a mental health service is a core function of mental health practitioners. This paper brings together what is already known about risk management and highlights areas for further investigation.

FIRST doubling, then tripling of the rate of production of the Lockheed Lightning fighter without expansion of plant size has been made possible, by ingenious engineering adaptation of automobile chain‐line assembly practice to aircraft manufacture. The accompanying illustrations show clearly some of the features of this system.