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This research aims to study the materials that compose older reinforced concrete bridges which are damaged and degrading to explain the mechanisms and origins of various disorders. Therefore, this work will contribute to providing answers on the capacity of nondestructive evaluation method during the diagnosis. In addition to the characterization of affected structures, it will aim to provide effective solutions for different serious pathologies.

In this context, two bridges located on NH16 and NH21, respectively, were studied in Annaba city (north-east Algeria), specifically in El-Hadjar municipality located in the central industrial zone of Pont-Bouchet. This study makes it possible to make conclusions from the in-depth diagnosis based on disorders exposition causes and mechanical characteristics evolution by non-destructive testing (NDT) tools. Furthermore, solutions are proposed, including conservation maintenance of these degraded structures.

All degradations can be the result of several factors: either human (poor design) or chemical (surface water, wastewater and groundwater quality (acidic or basic)). In addition to other natural causes (geological formations, flood phenomena or climate), NDT tools play a major role in the evaluating mechanical performance of degraded structures (resistance and hardness).

The NDT techniques can be transmitted to civil engineering experts because their training is limited regarding mechanical and structural construction.

NDT tools are the most suitable for in-situ assessing, and the concrete constructions health state, so far from financial problems.

Degraded bridge diagnosis by NDT testing is necessary for a thorough safety evaluation (mechanical performance, strength and deformability), to protect human lives and design durability.

This is an original paper which contains new information at different scales and from special fields, based on an evaluation using NDT tools on real degraded structures. It can be used to improve the knowledge of materials employed in a bridge without performing expensive direct tests or the need for destroying it.

The purpose of this paper is to investigate the mechanical behavior of textile-reinforced concrete (TRC)-strengthened concrete columns with small eccentricity under chloride-wet-dry cycles.

A total of ten reinforced concrete (RC) columns were constructed and subjected to eccentric compression, and the effects of the slenderness ratio, a variable number of wet-dry cycles and the coupled effect of loading and a chloride environment were analyzed. One of the columns tested was unreinforced, whereas the remaining columns were strengthened laterally with TRC.

The results showed that a reduction in the slenderness ratio was conducive to the improvement of the bearing capacity of the reinforced column; however, the reinforcement effect of TRC tended to decrease with an increasing number of wet-dry cycles, and the coupled effect of loading and a chloride environment significantly degraded the compression performance of TRC-strengthened columns, with the damage becoming more serious with increase in the sustained load ratio.

In the next test, the duration of chloride-wet-dry cycles will be extended. In the same time, to obtain a clearer trend, the authors will also increase the number of specimens to obtain more data for drawing general conclusions.

The originality is to explore the feasibility of using cement-based materials (TRC) as a confinement technique in chloride environment. The investigations demonstrate that TRC has a good reinforcement effect on the concrete columns under chloride-wet-dry cycles. Finally, influence of each parameter is analyzed, which can be used as reference and foundation in actual application.

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

The purpose of this study is experimental research of the mechanical behavior of slab reinforced by cork composite patch submitted to an eccentric progressive compressive load applied to on impact rectangle of dimensions 28 × 23 cm². An analytical model and numerical modeling by finite elements are performed. This study is motivated by the evaluation of the effectiveness of this type of partial reinforcement to improve strength and ductility. The results are given by load-displacement curves, tensile damages cartography and ultimate strength histogram.

In experimental protocol, the following two parameters have been considered: the dimensions of the patch and the eccentricity of the load. The sections of the patches are calculated so that the ratio (XP/YP) patch is proportional to the ratio (LD/lD), with a step of 6 cm longitudinally and 4 cm transversely. Several dimensions patches are considered: (6 × 4) cm², (12 × 8) cm² and (18 × 12) cm². The eccentric punching loading test was performed with an eccentricity of the load (1/3) L’ and (2/3) L’ compared to the center of gravity of the slab. Taking into account the eccentricity of the load in estimating the rupture strength, the equations are developed. Thus, numerical simulations are carried, to extract tensile damages cartography.

The results show that the rupture begins with the appearance of cracks in the unreinforced area. For an eccentricity of 1/3L’, the best strength/section ratio is obtained for patch (12 × 8) cm², whereas for an eccentricity de 2/3L’, the patch (6 × 4) cm² gives a better resistance. The results highlight the influence of the composite on the ultimate load. The force-displacement relations are little modified in the elastic phase. The experimental results have been compared with the theoretical models showing a good correlation.

The strength and ductility are depended on the dimensions of the patch and the eccentricity of the load. The use of a patch to cover the most stressed area, in the event of an eccentric axial load is a very economical solution compared to the total reinforcement. The damage field shows that the evolution of cracks depends on dimensions and the position of the patch. Indeed, the eccentricity of the vertical load induces an additional bending moment that will influence the fracture surface. The rupture load and ultimate displacement increase with the surface of the patch.

Fatigue failure is an important criterion to be considered in the design of structures and mechanical components. Catastrophic failure of structures in service conditions can be avoided using adequate techniques to detect and localize fatigue damage. Modal analysis is a tool used in mechanical and structural engineering to estimate dynamic properties and also to monitor the health of structures. If modal analysis is applied periodically to a structure, fatigue damage can be detected and localized and the fatigue life can be extended by means of suitable reinforcement and repairing. The paper aims to discuss these issues.

The experimental results corresponding to the fatigue tests carried out on a steel S-275 cantilever beam are presented. Operational modal analysis was applied periodically to the beam in order to study the variation of modal parameters during the tests and the stresses were estimated combining a numerical model and the acceleration modal coordinates measured at discrete points of the structure. The experimental results are compared with those predicted applying the S-N model of Eurocode 3.

A methodology that combines a finite element model and the experimental responses of a structure has been applied to estimate the stress time histories of a cantilever beam clamped to a foundation through a steel plate. The estimated stresses have been used to predict the fatigue damage according to the Eurocode 3. Due to the fact that no information of the scatter is provided by this code (EC3), only the number of cycles corresponding to a probability of failure of 5 percent can be predicted.

The proposed methodology can be applied to real structures in order to know the accumulated fatigue damage in real time.

This paper aims to explore the history of Anglican churches in Malaysia and discusses their typical features and their respective maintenance practices.

A narrative review of 84 literacy sources published between 1967 and 2020 on the development and features of Anglican churches in Malaysia, along with recommendations on maintenance practices from the asset and facilities management perspective. The exploration of churches’ features follows three main disciplines in building maintenance according to the Jabatan Kerja Raya Guideline for as-built buildings in Malaysia.

The findings of the study have then been tabulated to form a maintenance framework to recommend suitable maintenance practices on specific building components based on different materials. The paper argues that as places of worship, the assets of religious facilities are intangible compared to any other types of building that serve a tangible function (i.e. shelter, commercial or industrial operation). Throughout the exploration of their maintenance practices suggested by vast sources of literature, it is proven that the maintenance of churches is not as straightforward as merely remedying the defects, but it requires the maintenance to radically minimise any disturbance to their aesthetics, thus making maintenance a more challenging task at churches.

This paper proposes a maintenance framework for Anglican churches in Malaysia by categorising building disciplines and their corresponding building components, which supports future research to improve the maintenance practices of religious facilities.

The purpose of this paper is to investigate individuals’ lived experience of camping, and to explore the effects of camping on relationships.

The research adopted a descriptive phenomenological approach (Langdridge, 2007). Guided interviews were carried out with four participants, recalling their most memorable camping experience, with the aid of photographs to elicit memories. Analysis followed Colaizzi's (1978) seven-stage analysis and findings were discussed in relation to Duck's model of relationship dissolution (1981).

Findings concern how camping is a great opportunity for couples, and friends, to re-connect with each other, reinforcing existing bonds and strengthening weakened ones. Other findings included enjoyment of the tranquillity and relaxation the natural environment provided, and for some the sense of adventure was encouraged, and the idea of “being away” from the usual surroundings was reported to be of relational benefit.

The discovery of the benefit for camping on relationships is a unique and valuable contribution in this field because it has shown that camping can maintain, and evolve, relationships. As such, camping could be used as a bonding or relationship support intervention.

This paper describes state‐of‐the‐art optical technology, employing Bragg gratings, which has been used to develop an Optical Fibre Strain Sensing System. This system is capable of providing actual strain and temperature information for new and existing structures. The sensors, written into the core of standard single mode optical fibre, are embedded into the composite material, or surface bonded on to the structure for load monitoring. The system can be used as a design tool for engineers, for composite cure‐monitoring, setting up of rigs etc., or can be used as a health monitoring tool to periodically monitor loading of bridges, buildings and pipelines.

This article proposes that survival can be a legitimate organizational goal, challenging a common view that dismisses it as unambitious or contrary to innovation. Drawing parallels from nature and survival strategies across various systems, it advocates that organizations, much like living organisms, should prioritize survivability (i.e. ability to survive) to ensure long-term success. Contrary to being seen as limiting, survival, when understood in its broad sense, can encompass and enhance performance goals such as growth. The article outlines the ERP factors —efficiency, resilience and prominence—as key to achieving survivability, offering a framework for organizations to manage resources, adapt to external forces and balance visibility to thrive amidst challenges.

Conceptual framework.

This model introduces the significance of survivability as an organizational goal.

This article argues for the consideration of survival as an overarching organizational goal, challenging the prevalent view that dismisses it as unambitious or contrary to innovation.