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The purpose of this study is to investigate the effect of various heat conditions on the durability of eggshell powder (ESP)–flyash (FA) geopolymer subjected to wetting–drying cycles.

In this study, two waste materials, ESP and FA, which are destined for landfills, were used as precursors to produce geopolymers in a sustainable manner. The mixture of Na₂SiO₃ and NaOH was used as a liquid alkaline activator in geopolymerization. The ESP and FA content were varied as 30, 50 and 70% and Na₂SiO₃/NaOH ratios were varied as 0.5, 1 and 2. Geopolymer samples were cured at three heat conditions: 25°C (ambient temperature), 50°C and 80°C for seven days prior to durability tests.

The results of this study revealed that the strength loss of the geopolymer decreases with an increase in curing temperature up to 50°C and then increases for higher temperature up to 80°C. Further, the strength loss of the geopolymer decreases with an increase in FA replacement and Na₂SiO₃/NaOH ratio. Geopolymer composites exhibited early strength development because of the inclusion of calcium-rich ESP. The weight loss of the ESP–FA geopolymer follows a similar pattern of strength loss. Geopolymer samples previously cured at optimum heat condition of 50°C for seven days exhibited higher durability.

The inclusion of calcium-rich ESP in FA-based geopolymer is novel research. As ESP–FA geopolymer composites show higher mechanical strength and higher durability compared to Indian standards, the potential use of this geopolymer can be in road subbases/subgrades.

The purpose of this paper is to focus on the durability of underwater non-dispersible concrete in seawater environment.

In this paper, ten groups of underwater non-dispersible concrete mixtures were designed, and the anti-dispersibility and fluidity of the mixtures were tested.

The durability test analysis shows that different pouring methods have different effects on the durability of concrete. The durability of concrete poured on land is better than that poured in water. Different mineral admixtures have different effects on the durability of concrete: the frost resistance of the underwater non-dispersible concrete specimens with silica fume is the best; the impermeability and chloride ion permeability of the non-dispersible underwater concrete specimens with waterproofing agent are the best; and the alternation of wetting and drying has adverse effects on the durability indexes of the non-dispersible underwater concrete.

The durability of underwater non-dispersible concrete is tested and the results can be used for reference in engineering practice.

The purpose of this paper is to investigate the durability of radio‐frequency identification (RFID) chips assembled on flexible substrates (paper and foil), with materials evaluated with regard to mechanical stresses and dependence on the applied substrate, antenna materials, chip pad printing and chip encapsulation.

RFID chips were assembled to antennas screen printed on flexible substrates. Shear and bending tests were conducted in order to evaluate the mechanical durability of the chip joints depending on the materials used for mounting the RFID chip structures. X‐ray inspection and cross sectioning were performed to verify the quality of the assembly process. The microstructure and the resistance of the materials used for chip pads were investigated with the aim of determining the conductivity mechanism in the printed layers.

Addition of carbon nanotubes to the conductive adhesive (CA) provided a higher shear force for the assembled RFID chips, compared to the unmodified conductive adhesive or a polymer paste with silver flakes. However, this additive resulted in an increase in the material's resistance. It was found that the RFID substrate material had a significant influence on the shear force of mounted chips, contrary to the materials used for printing antennas. The lower shear force for chips assembled on antennas printed on paper rather than on foil was probably connected with its higher absorption of solvent from the pastes. Increasing the curing temperature and time resulted in an additional increase in the shear force for chips assembled to antennas printed on foil. A reverse dependence was observed for chips mounted on the antennas made on paper. An improvement in the durability of the RFID chip structures was achieved by chip encapsulation. Bending tests showed that a low‐melting adhesive was the best candidate for encapsulation, as it provided flexibility of the assembled structure.

Further studies are necessary to investigate the mechanical durability of RFID chips assembled with a conductive adhesive, with different addition levels and types of carbon nanotubes.

The results revealed that the best candidate for providing the highest RFID chip durability related to mechanical stresses was the low‐melting adhesive. It can be recommended for practical use, as it simplified the assembly process and reduced the curing step in the encapsulation of the RFID devices. From the results of shear testing, conductive adhesives with carbon nanotubes can be used in RFID chip assembly because of their ability to increase the shear force of joints created between the antenna and the chip.

In this paper, the influence of the materials used for antenna, chip pads, encapsulation and the curing conditions on the mechanical durability (shear and bending) of RFID chips was analyzed. Commercial and elaborated materials were compared. Some new materials containing a conductive adhesive and carbon nanotubes were proposed and tested in RFID chip assembly to antennas printed on flexible substrates (paper and foil).

Among various efforts pursued to produce fuel efficient vehicles, light weight engineering (i.e. the use of low‐density structurally‐efficient materials, the application of advanced manufacturing and joining technologies and the design of highly‐integrated, multi‐functional components/sub‐assemblies) plays a prominent role. In the present work, a multi‐disciplinary design optimization methodology has been presented and subsequently applied to the development of a light composite vehicle door (more specifically, to an inner door panel). The door design has been optimized with respect to its weight while meeting the requirements /constraints pertaining to the structural and NVH performances, crashworthiness, durability and manufacturability. In the optimization procedure, the number and orientation of the composite plies, the local laminate thickness and the shape of different door panel segments (each characterized by a given composite‐lay‐up architecture and uniform ply thicknesses) are used as design variables. The methodology developed in the present work is subsequently used to carry out weight optimization of the front door on Ford Taurus, model year 2001. The emphasis in the present work is placed on highlighting the scientific and engineering issues accompanying multidisciplinary design optimization and less on the outcome of the optimization analysis and the computational resources/architecture needed to support such activity.

The inclusion of pozzolans like pulverised fuel ash (PFA), silica fume (SF) and metakaolin (MK) enhances the properties of concrete both in fresh and hardened states. In the case of high performance concrete (HPC), their role in enhancing the workability, strength and durability is extremely significant. However HPC has been observed to be more vulnerable than normal strength concrete when exposed to elevated temperatures. This paper presents an overview and discusses the strength and durability performance of high‐performance pozzolanic concretes incorporating PFA, SF, and MK subjected to elevated temperatures. Various researchers have demonstrated that addition of silica fume causes HPC to perform poorly when subjected to elevated temperatures. Higher loss of strength and spalling risks are also associated with it. Addition of PFA and MK has been found to improve the fire performance of HPC both in terms of residual strength and durability.

Earthen construction does not meet today’s requirements due to certain limitations such as low water resistance and its high vulnerability to cracking damage. The purpose of this study is to improve the mechanical properties and low durability of adobe blocks by incorporating date palm wastes as a natural reinforcement and lime as a stabilizer.

Soil from the region of Biskra in Algeria was mixed with sand and lime in suitable ratios. Then, date palm wastes were added to the previous mixture at different ratios (0.3%, 0.6% and 0.9%) by dry mix weight to manufacture adobes. Cubical and cylindrical specimens were prepared and tested in a laboratory to investigate the curing time, mechanical and durability characteristics of the formulated blocks. In addition, X-ray diffraction and scanning electron microscopy (SEM) tests were used to identify the materials.

It has been observed that the addition of lime to the soil is very beneficial for its stabilization, in particular for an optimum of 12%. The presence of date palm waste in the mixture (soil + lime) generated a significant improvement in tensile strength reaching a rate of about 67%. The same observation was made for the tests of resistance to dry abrasion, resistance to erosion, attack by external sulphate and wetting/drying. However, for cases of compressive strength, water absorption and swelling an unfavorable effect was recorded.

Based on the above-mentioned findings, this paper presents a novel solution to increase the durability of adobe materials using date palm wastes with oven curing at 65°C for about nine days. Adopting such an approach would certainly encourage building durable mud housing on a large scale. This can contribute to solving the acute housing shortage, particularly in poor countries.

The selection of lime mortars for masonry structures can be an important component of a repair or new build project. This selection is considered difficult due to the number of variables to consider during the decision‐making process and the perceived inherent complexity of the materials. The purpose of this paper is to discuss the selection process for determining suitable natural hydraulic lime repair mortars for masonry.

The paper presents a conceptual and practical framework for the determination of suitable lime mortars for repair and construction of masonry structures, drawing and building on relevant, literature and existing best practice guidance on specification.

The use of various relatively newly produced data sets pertaining to durability can aid in the appropriate selection of lime mortars. These determinants must however, be correlated with traditional evaluation of exposure levels, building detailing and moisture handling performance. Building condition survey of the existing fabric is essential to enable refinement of the selection process of these mortars. The adjustment of the initially identified mortars highlighted in the best practice guide may potentially benefit from modification based on the aforementioned factors.

Whilst data exist to help the practitioner select hydraulic lime mortars they have never been correlated with the tacit and expressed protocols for survey and the evaluation of the performance of structures.

In the maritime industry, it is vital to have a reliable forecast of container shipping demand. Although indicators of economic conditions have been used in modeling container shipping demand on major routes such as those from East Asia to the USA, the duration of such indicators’ effects on container movement demand have not been systematically examined. To bridge this gap in research, this study aims to identify the important US economic indicators that significantly affect the volume of container movements and empirically reveal the duration of such impacts.

The durability of economic indicators on container movements is identified by a vector autoregression (VAR) model using monthly-based time-series data. In the VAR model, this paper can analyze the effect of economic indicators at t-k on container movement at time t. In the model, this paper considers nine US economic indicators as explanatory variables that are likely to affect container movements. Time-series data are used for 228 months from January 2001 to December 2019.

In the mainland China route, “building permission” receives high impact and has a duration of 14 months, reflecting the fact that China exports a high volume of housing-related goods to the USA. Regarding the South Korea and Japan routes, where high volumes of machinery goods are exported to the USA, the “index of industrial production” receives a high impact with 11 and 13 months’ duration, respectively. On the Taiwan route, as several types of goods are transported with significant shares, “building permits” and “index of industrial production” have important effects.

Freight demand forecasting for bulk cargo is a popular research field because of the public availability of several time-series data. However, no study to date has measured the impact and durability of economic indicators on container movement. To bridge the gap in the literature in terms of the impact of economic indicators and their durability, this paper developed a time-series model of the container movement from East Asia to the USA.

The first Austrian school was preoccupied with the nature of capital, its time dimension, and the necessity of interest. The second school also focused on economic dynamics, but with an orientation toward issues related to entrepreneurial activity as well as the use of information and knowledge in economic evolution. The third Austrian school, which was organized around Karl Menger's mathematical colloquium in Vienna, clarified the necessary and sufficient conditions for static and dynamic economic equilibriums. In addition, it created the foundations of economic game and negotiation theories.

For coastal bridges, the ability to recover traffic functions after the earthquake has crucial implications for post-disaster reconstruction, which makes resilience become a significant index to evaluate the seismic behavior. However, the deterioration of the material is particularly prominent in coastal bridge, which causes the degradation of the seismic behavior. As far, the research studies on resilience of coastal bridges considering multiple degradation factors and different disaster prevention capability are scarce. For further evaluating the seismic behavior of coastal bridge in the long-term context, the seismic resilience is conducted in this paper with considering multiple durability damage.

The fuzzy theory and time-varying fragility analysis are combined in this paper to obtain the life-cycle resilience of coastal bridges.

The results show that durability damage has a remarkable impact on the resilience. After 100 years of service, the seismic resilience of bridge with poor disaster-prevention capability has greatest reduction, about 18%. In addition, the improvement of the disaster prevention capability can stabilize the resilience of the bridge at a higher level.

In this paper, the time-varying fragility analysis of case bridge are evaluated with considering chloride ion erosion and concrete carbonization, firstly. Then, combining fuzzy theory and fragility analysis, the triangular fuzzy values of resilience parameters under different service period are obtained. Finally, the life-cycle resilience of bridge in different disaster prevention capability is analyzed.