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In order to reduce the impact of bridge construction on traffic under the bridge, the construction of bridges for some important traffic nodes usually adopts the swivel construction method. The spherical hinge is a rotating mechanism located between the bottom of the pier and the bridge cap, and is subjected to tremendous vertical pressure. According to the mechanical characteristics of the spherical hinges, this paper applies the ultra-high performance concrete (UHPC) material to the spherical hinge. The spherical hinge is subjected to a compression test to test its mechanical behavior. This paper aims to discuss this issue.

In order to test the mechanical behavior of the UHPC spherical hinge, multiple sets of 100 mm UHPC spherical hinge specimens were prefabricated. Through the universal testing machine to measure the compressive strength of specimens, draw the force-displacement curve to analyze the failure mechanism and establish the stress calculation formula of the spherical hinge at each point along the radial direction.

Through the test, the compressive strength of UHPC spherical hinge is obtained, and the influencing factors of UHPC spherical hinge strength are found: reducing water–cement ratio, increasing steel fiber content and length and changing steel fiber arrangement direction can effectively improve the compression strength of UHPC spherical hinge.

For the first time, UHPC materials were applied to the spherical hinge structure, the UHPC spherical hinge diameter is 1/3 of the diameter of the reinforced concrete spherical hinge, which is equivalent to the diameter of the steel spherical hinge. By applying the UHPC spherical hinge, the manufacturing cost is reduced, the process is simple, and the construction difficulty is reduced.

The purpose of this paper is to develop a highly miniaturized wireless inertial sensor system based on a novel 3D packaging technique using a flexible printed circuit (FPC). The device is very suitable for wearable applications in which small size and lightweight are required such as body area network, medical, sports and entertainment applications.

Modern wireless inertial measurement units are typically implemented on a rigid 2D printed circuit board (PCB). The design concept presented here is based around the use of a novel planar, six‐faceted, crucifix or cross‐shaped FPC instead of a rigid PCB. A number of specific functional blocks (such as microelectromechanical systems gyroscope and accelerometer sensors, microcontroller (MCU), radio transceiver, antenna, etc.) are first assigned to each of the six faces which are each 1 cm² in area. The FPC cross is then developed into a 1 cm³, 3D configuration by folding the cross at each of five bend planes. The result is a low‐volume and lightweight, 1 cm³ wireless inertial sensor that can sense and send motion sensed data wirelessly to a base station. The wireless sensor device has been designed for low power operation both at the hardware and software levels. At the base station side, a radio receiver is connected to another MCU unit, which sends received data to a personal computer (PC) and graphical user interface. The industrial, scientific and medical band (2.45 GHz) is used to achieve half duplex communication between the two sides.

A complete wireless sensor system has been realized in a 3D cube form factor using an FPC. The packaging technique employed during the work is shown to be efficient in fabricating the final cubic system and resulted in a significant saving in the final size and weight of the system. A number of design issues are identified regarding the use of FPC for implementing the 3D structure and the chosen solutions are shown to be successful in dealing with these issues.

Currently, a limitation of the system is the need for an external battery to power the sensor system. A second phase of development would be required to investigate the possibility of the integration of a battery and charging system within the cube structure. In addition, the use of flexible substrate imposes a number of restrictions in terms of the ease of manufacturability of the final system due to the requirement of the required folding step.

The small size and weight of the developed system is found to be extremely useful in different deployments. It would be useful to further explore the system performance in different application scenarios such as wearable motion tracking applications. In terms of manufacturability, component placement needs to be carefully considered, ensuring that there is sufficient distance between the components, bend planes and board edges and this leads to a slightly reduced usable area on the printed circuit.

This paper provides a novel and useful method for realizing a wireless inertial sensor system in a 3D package. The value of the chosen approach is that a significant reduction in the required system volume is achieved. In particular, a 78.5 per cent saving in volume is obtained in decreasing the module size from a 25 to a 15 mm³ size.

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the environment. Also, fly ash is a material with sustainable properties. Therefore, this paper aims to focus on the development of sustainable construction materials using 100% high-calcium fly ash and potassium hydroxide (KOH)-based alkaline solution and study the engineering properties of the resulting fly ash-based geopolymer concrete. Laboratory tests were conducted to determine the mechanical properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In phase I of the study, carbon nanotubes (CNTs) were added to determine their effect on the strength of the geopolymer mortar. The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce similar (comparable) strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates a considerable amount of heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond was unable to form a stronger bond. This study also determined that the addition of CNTs to the mix makes the geopolymer concrete tougher than the traditional concrete without CNT.

Tests were conducted to determine properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In Phase I of the study, CNTs were studied to determine their effect on the strength of the geopolymer mortar.

The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce the same strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates too much heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond. This study also determined that the addition of CNTs to the mix makes the concrete tougher than concrete without CNT.

This study was conducted at the construction engineering and management concrete laboratory at North Dakota State University in Fargo, North Dakota. All the experiments were conducted and analyzed by the authors.

From recent laboratory research monofilament and fibrillated polypropylene fibres were used in structural concrete and have been tested against 150 freeze/thaw cycles. The findings show monofilament fibres to play a significant role in protecting the concrete matrix against the forces encountered. External cube integrity was shown to be a poor indicator of structural condition. A significant aspect of the work is the range of tests applied to the freeze/thaw concrete cubes against the control sample. Strong evidence of condition was obtained from ultrasonic, compressive strength and weight loss. Surface scaling was not a satisfactory indication of the structural condition of the concrete.

Punching can trigger catastrophic failures in flat slabs because of its sudden nature resulting from exceeding the shear capacity of slabs. Effect of using recycled aggregate, as an environmental-friendly alternative to traditional RC structures, on punching behavior of these slabs was not sufficiently investigated in the literature. Hence, this paper aims to experimentally study the effect of using recycled coarse aggregate (RCA) on the punching shear capacity (PSC) of RC flat slabs. The RCA is produced by crushing of waste of concrete standard cubes obtained from compression tests.

A total of 12 slab-column connection specimens with different slab thicknesses (140, 160 and 200 mm) and different RCA percentages (0%, 30% and 70%) were prepared and tested under a central point load, to test its effect on the behavior of flat slabs. The punching failure loads of the tested specimens were compared with those obtained according to the provisions of different international building codes.

Compared with natural aggregate concrete, mixes with 30% and 70% RCA experienced reductions in the compressive that did not exceed 4% and 21%, while reductions of 4% and 13% were observed for the tensile strength, respectively. The increase in the amount of RCA reduced the PSC by 0%–7%, 0%–4% and 4%–10% for slabs with a thickness of 140, 160 and 200 mm, respectively. For slabs with punching shear reinforcement (PSR), ACI 318 provided the closest estimation for the PSC by 9%, whereas EURO 2 overestimated the PSC by 25% and ECP 203 underestimated the PSC by 41%.

The provided conclusions are obtained from the conducted experimental work where a constant W/C ratio, aggregate type and a maximum aggregate size of 19 mm for the RCA were adopted.

Enhancement in the behavior of flat slabs with various thicknesses and amounts of RCA because of introducing PSR is experimentally evaluated. The failure loads of the tested slabs with recycled and normal coarse aggregates were compared against different code provisions.

By examining the literature on the ethical dilemmas of H/RM practitioners, the paper aims to put an “H” in H/RM.

Analysing the significant contribution which H/RM scholars have made in studying the ethical dilemmas of H/RM practitioners, the paper builds a view of an H/RM practitioner as a “conscientious HR manager” loosely connected to an ethical dilemma, a “Rubik's Cube”. Using these linguistic devices to simplify others scholarly work, the paper introduces a complex autopoietic system to provide a more “connected knowing” of ethical dilemmas and the “H” in H/RM.

Generalising from this analysis, the paper connects a social sub‐system (H/RM) with a living human system.

Naturalistic “grounds” for launching a normative critique of H/RM that celebrates humans as social and biological animals are provisionally outlined.

The paper adapts Capra's complex autopoietic system to present a normative critique of H/RM from the Darwinian left.

The purpose of this paper is to explore the strategy for latecomers in large developing countries under globalization. The relationship between innovation and learning is deeply studied.

The paper formulates an in‐depth case study on the digital video player industry through consideration of government documents, reports, and research papers; intensive interviews; and questionnaire study.

The firms in developing countries might be able to innovate before they can match the firms in advanced countries in technological capabilities, and innovation is the most effective way of learning. The firms can achieve competitive advantage owing to the effect of the national value network, the nature of architectural technology, and the relationships between them in product development. The national market should be deliberately taken as a strategic asset for the technological learning and latecomers should learn how to exploit the advantage of globalization.

The paper tries to understand how firms in developing countries conduct learning by innovating to build their competitive advantages.

The Learning Cube in its early development stages is a simple diagnostic tool used to analyse and evaluate a training programme in the People's Republic of China: the China‐EEC Management Programme (CEMP). The Learning Cube is presented in outline, with a description of all its dimensions and their meanings. CEMP is summarised and assessed with new proposals set out. The model is then applied to the CEMP situation and possible course improvements and conclusions are presented.

This paper aims to investigate the necessary requirements that a concrete reinforcement material must satisfy; namely the ability to resist tensile forces and have good bond strength while providing structural qualities of toughness and flexural strength.

The bond and strength properties were mainly tested in a paired comparison test using 6 mm diameter steel and fibre reinforced polymer (FRP) rebar specimens in beams and cubes. Bond strength was examined using 12 concrete cube specimens of 150 mm, six cubes had steel rebar and six had FRP rebar inserted through the full depth of the cube and they were subject to pull out tests. To determine flexural strength and toughness, a three point loading test was performed to provide load/extension data on 28 500×100×100 mm concrete beams. A total of 14 beams were cast with steel rebar and 14 were cast with FRP rebar.

The results showed for equal diameter bars the FRP specimens had outperformed steel in each test. Failure modes of FRP specimens showed higher degrees of toughness when compared to steel.

Steel rebar has a long and proven track record of satisfactory use in reinforced concrete. For designers and clients to change from traditionally used materials, there is a need for investigative research to prove the worth of the new material. This paper goes part of the way to fulfil this need.

This study aims to provide resiliency against earthquakes to the framework of an urban road network and to construct a comprehensive model with sufficient computational detail to assist metropolitan managers as a decision support tool in emergency situations via parametric analysis (model behaviour analysis with parameter changes) to quantify the consequences of decisions.

Performed stages are: developing existing resilience assessment frameworks for use against earthquakes in urban road networks, identifying earthquake scenarios and estimating the weight of components using AHP, including an example modelling of Tehran; and developing modelling software (using Matlab®).

This study produced a software that performs three-dimensional (3D) graphical modelling, resiliency index measurements and its parametric analyses for the road networks against earthquakes. Based on this model, a prioritized list of upgrades is also introduced. The developed tool also addresses issues regarding the allocation of limited resources between the network components.

Because of the novelty of the study, there is limited literature on this topic.

The developed model provides urban managers with a comprehensive list of upgrades and empowering them to graphically and numerically evaluate the resiliency changes as they alter the parameters of these measures and balance their decisions based on available funding.

In contrast to previous studies, this study has focused on all of these three keywords: resiliency, earthquake and road networks, and not only two of them.