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This chapter examines the role of multimodal rhetoric in processes of theorization. Empirically, we investigated the theorization process of a highly disruptive innovation in the history of architecture: reinforced concrete. Relying on archival data from a prominent French architectural journal in the period from 1885 to 1939, we studied the rhetorical modes at play in the theorization of reinforced concrete. First, we found that theorization entailed two recursive activities: dramatization and evaluation. While dramatization relies on both verbal and visual (i.e., multimodal) means, evaluation relies on verbal means. We integrated these components into a dynamic model of theorization that explains how visual discourse contributes to theorization beyond the effects of verbal discourse.

The purpose of this paper is to investigate a dissipative reinforced concrete structural wall that can improve the behavior of a tall multi-storey building. The main objective is to evaluate the damage of a dissipative wall in comparison with that of a solid wall.

In this paper, a comparative nonlinear dynamic analysis between a dissipative wall and a solid wall is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a reinforced concrete structural wall is to create a slit zone with short connections. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behavior. The behavior of these short connections is modeled using the finite element software ANSYS 12. In this study, the authors propose to evaluate the damage of reinforced concrete slit walls with short connections using seismic analysis.

Using the computational model created in the second section of the paper, a seismic analysis of a dissipative wall from a multi-storey building was done in the third section. From the results obtained, the advantages of the proposed model are observed.

A simple computational model was created that consume low processing resources and reduces processing time for a dynamic pushover analysis. Unlike other studies on slit walls with short connections, which are focussed mostly on the nonlinear dynamic behavior of the short connections, in this paper the authors take into consideration the whole structural system, wall and connections.

In developing countries such as India, it is common practice to use low‐quality building materials, the strength of such materials reduce with time, which affects the lifespan of buildings. The wind, rain, seepage, and surface runoff are other key factors responsible for building damage and exterior degradation. The increasing industrial growth in and around urban areas is responsible for increasing industrial and anthropogenic emissions that are found to accelerate degradation of the buildings that affects their physical appearance. In an area prone to natural hazards such as earthquakes, volcanoes, subsidence, floods, lightning, tornados, and cyclone/hurricanes, huge amounts of damage throughout the globe has been experienced. For the purpose of assuring safety due to natural hazards, it is necessary to monitor the damage for its existence, its location and extent. Undetected damage may potentially lead to risk of vulnerability caused by natural hazards and eventually to catastrophic failure. Hence, rapid structural damage detection is essential and important to save human life due to failure of structures or buildings. Most of the time, human loss occurs due to damage to the buildings. This paper aims to address these issues.

In the present study, numerous experiments have been carried out on two reinforced concrete building test specimens and on seven existing reinforced cement concrete structures.

The results presented here in this study show that the vibration measurements can be used to monitor the health of framed reinforced cement concrete buildings.

The present study is part of doctoral thesis of Varinder S. Kanwar, an original research work.

The purpose of this paper is to investigate a reinforced concrete multi-storey building with dissipative structural walls. These walls can improve the behaviour of a tall multi-storey building. The authors’ main objective is to evaluate the damage of a building with dissipative walls in comparison with that of a building with solid walls.

In this paper, a comparative nonlinear dynamic analysis between a building with slit walls and then the same building with solid walls is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a building with structural walls is to create slit zones with short connections in to the walls. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behaviour. The hysteretic rules and parameters of these short connections were proposed by the authors and used in this analysis. In this study, the authors propose to evaluate the damage of a building with reinforced concrete slit walls with short connections using seismic analysis.

Using the computational model created by the authors for the slit wall, a seismic analysis of a multi-storey building with slit walls was done. From the results obtained, the advantages of the proposed model are observed.

Using a simple computational model, created by the authors, that consume low processing resources and reduces processing time, a nonlinear dynamic analysis on high-rise buildings was done. Unlike other studies on slit walls with short connections, which are focused mostly on the nonlinear dynamic behaviour of the short connections, in this paper the authors take into consideration the whole structural system, wall, connections and frames.

This paper aims to model the performances of frames structures by comparing the predictions of ordinary control concrete (CC) and concretes reinforced by fibers. Two types of steel fibers were used in this work, industrial steel fibers (ISF) and tire-reclaimed fibers obtained by cutting virgin steel tire-cord to 50 mm, noticed virgin steel fibers (VSF). In total, 3% of VSF are used. The results obtained in this paper clearly show the contribution of fibers in improving the global and local behavior of the frames structures. VSF gives the same or better overall behavior as the use of industrial fibers for the same percentage of fibers, with the advantage that VSF contributes to the protection of the environment and limit the wastage of steel.

This work was carried out using the commercial finite element code Abaqus/Explicit. The behavior of the different concretes used in this study was modeled by the concrete damage plasticity (CDP) constitutive law. The methodology adopted to complete this work consisted in identifying, by calibration of the available experimental results with the numerical predictions, the parameters of the corresponding CDP model for each of the concretes used in this work. To this end, the authors have successively identified the CDP parameters for the CC-V (control concrete used by Vecchio and Emara, 1992) used in frame structure (R + 1). Subsequently, the CDP parameters of the CC-T (control concrete used by Tlemat, 2004), the CVSF (concrete with virgin steel fibers) and the CISF-1 (concrete with industrial steel fibers type 1, ISF-1) are identified using the experimental results of beams under bending tests. Once the model parameters were determined for each concrete, the authors conducted a series of simulations to show the benefit of introducing claimed and industrial fibers in frame structure (R + 1) and (R + 2). This approach recommends the use of concrete reinforced with steel fibers, mainly 6% by mass of VSF and ISF-1, in place of ordinary concrete in new construction to increase the resistance of structures and contribute, if applicable, to the protection of the environment.

The main findings of this study can be summarized by: the strength and ductility of the frames structures made of concrete fiber are significantly increased. The use of tire-reclaimed steel fibers (VSF) gives the same or better overall behavior as the use of industrial fibers. In addition to their good mechanical contribution, the tire-reclaimed fibers contribute to the protection of the environment and limit the wastage of steel. The use of fibers reduces the cracking zones in concrete fiber frames structures. The usefulness of distinguishing the interstory displacement limits set by codes, in particular, uniform building code (UBC-97), for ordinary concretes and concrete reinforced with fibers is addressed.

The contribution of tire-reclaimed and industrial fibers on the strength and ductility of reinforced concrete-frames structures is addressed. The use of tire-reclaimed steel fibers gives the same or better overall behavior as the use of industrial fibers, the tire-reclaimed fibers having the advantage of contributing to the protection of the environment and limiting the wastage of steel. The paper also points to the usefulness of distinguishing the interstory displacement limits set by codes, in particular UBC-97, for ordinary concrete and concrete reinforced with fibers, in accordance to the predictions of the capacity curves.

Performance of the structure depends on design, construction, environment, utilization and reliability aspects. Other factors can be controlled by adopting proper design and construction techniques, but the environmental factors are difficult to control. Hence, mostly in practice, the environmental factors are not considered in the analysis and design appropriately; however, their impact on the performance of the structures is significant along with the design life. It is in this light that this paper aims to perform the time-dependent performance analysis of reinforced concrete structures majorly considering environmental factors.

To achieve the intended objective, a simply supported reinforced concrete beam was designed and detailed as per the Euro Code (EC2). The time-dependent design parameters, corrosion parameters, creep and shrinkage were identified through thorough literature review. The common empirical equations were modified to consider the identified parameters, and finally, the time-dependent performance of reinforced concrete beam was performed.

Findings indicate that attention has to be paid to appropriate consideration of the environmental effect on reinforced concrete structures. In that, the time-dependent performance of reinforced concrete beam significantly decreases with time due to corrosion of reinforcement steel, creep and shrinkage.

However, the Euro code, Ethiopian code and Indian code threat the exposure condition of reinforced concrete by providing corresponding concrete cover that retards the corrosion initiation time but does not eliminate environmental effects. The results of this study clearly indicate that the capacity of reinforced concrete structure degrades with time due to corrosion and creep, whereas the action on the structure due to shrinkage increases. Therefore, appropriate remedial measures have to be taken to control the defects of structures due to the environmental factors to overcome the early failure of the structure.

The purpose of this paper is to present current challenges in concrete conservation and how the Getty Conservation Institute (GCI) is responding to these challenges. The Concrete Conservation Project initiated by the GCI is aimed at advancing the practice of conserving historic concrete structures through the creation and dissemination of information.

The scope of the project was defined through discussions in experts meetings, development of annotated bibliography and literature review. The project proposes to face the identified issues with the dissemination of information on case studies, development of guidance documents, training opportunities and scientific research.

Despite the existing well-established repair industry for concrete structures generally, current data on concrete repair do not meet the needs of conservation professionals, there is little information on the efficacy and durability of existing repair solutions, shortage of training opportunities, and there is a lack of technical guidelines focused on concrete conservation.

Conserving concrete is a nascent area of preservation practice facing multiple challenges. Reinforced concrete is the most commonly used building material of the twentieth century. As the heritage of the twentieth century is increasingly recognized as worthy of conservation, conserving concrete has become a priority. The history of this material reveals a story of innovation, radical advancement in material and structural engineering, and correspondingly daring responses by architects, together creating a huge array of reinforced concrete structures from the ordinary to the extraordinary.

Damage to reinforced concrete (RC) structural elements is inevitable. Such damage can be the result of several factors, including aggressive environmental conditions, overloading, inadequate design, poor work execution, fire, storm, earthquakes etc. Therefore, repairing and strengthening is one way to improve damaged structures, so that they can be reutilized. In this research, the use of an ultra high-performance fibre-reinforced concrete (UHPFRC) layer is proposed as a strengthening material to rehabilitate damaged-RC beams. Different strengthening schemes pertaining to the structural performance of the retrofitted RC beams due to the flexural load were investigated.

A total of 13 normal RC beams were prepared. All the beams were subjected to a four-point flexural test. One beam was selected as the control beam and tested to failure, whereas the remaining beams were tested under a load of up to 50% of the ultimate load capacity of the control beam. The damaged beams were then strengthened using a UHPFRC layer with two different schemes; strip-shape and U-shape schemes, before all the beams were tested to failure.

Based on the test results, the control beam and all strengthened beams failed in the flexural mode. Compared to the control beam, the damaged-RC beams strengthened using the strip-shape scheme provided an increase in the ultimate load capacity ranging from 14.50% to 43.48% (or an increase of 1.1450 to 1.4348 times), whereas for the U-shape scheme beams ranged from 48.70% to 149.37% (or an increase of 1.4870–2.4937 times). The U-shape scheme was more effective in rehabilitating the damaged-RC beams. The UHPFRC mixtures are workable, as well easy to place and cast into the formworks. Furthermore, the damaged-RC beams strengthened using strip-shape scheme and U-shape scheme generated ductility factors of greater than 4 and 3, respectively. According to Eurocode8, these values are suitable for seismically active regions. Therefore, the strengthened damaged-RC beams under this study can quite feasibly be used in such regions.

Observations of crack patterns were not accompanied by measurements of crack widths due to the unavailability of a microcrack meter in the laboratory. The cost of the strengthening system application were not evaluated in this study, so the users should consider wisely related to the application of this method on the constructions.

Rehabilitation of the damaged-RC beams exhibited an adequate structural performance, where all strengthened RC beams fail in the flexural mode, as well as having increment in the failure load capacity and ductility. So, the used strengthening system in this study can be applied for the building construction in the seismic regions.

Aside from equipment, application of this strengthening system need also the labours.

The use of sand blasting on the surfaces of the damaged-RC beams, as well as the application of UHPFRC layers of different thicknesses and shapes to strengthen the damaged-RC beams, provides a novel innovation in the strengthening of damaged-RC beams, which can be applicable to either bridge or building constructions.

This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the non-dimensional capacity parameters for the axial and flexural load-carrying capacity of reinforced concrete (RC) sections for heating and the subsequent post-heating phase (decay phase) of the fire.

The sectional analysis method is used to determine the moment and axial capacities. The findings of sectional analysis and heat transfer for the heating stage are initially validated, and the analysis subsequently proceeds to determine the load capacity during the fire’s heating and decay phases by appropriately incorporating non-dimensional sectional and material parameters. The numerical analysis includes four fire curves with different cooling rates and steel percentages.

The study’s findings indicate that the rate at which the cooling process occurs after undergoing heating substantially impacts the axial and flexural capacity. The maximum degradation in axial and flexural capacity occurred in the range of 15–20% for cooling rates of 3 °C/min and 5 °C/min as compared to the capacity obtained at 120 min of heating for all steel percentages. As the fire cooling rate reduced to 1 °C/min, the highest deterioration in axial and flexural capacity reached 48–50% and 42–46%, respectively, in the post-heating stage.

The established non-dimensional parameters for axial and flexural capacity are limited to the analysed section in the study owing to the thermal profile, however, this can be modified depending on the section geometry and fire scenario.

The study primarily focusses on the degradation of axial and flexural capacity at various time intervals during the entire fire exposure, including heating and cooling. The findings obtained showed that following the completion of the fire’s heating phase, the structural capacity continued to decrease over the subsequent post-heating period. It is recommended that structural members' fire resistance designs encompass both the heating and cooling phases of a fire. Since the capacity degradation varies with fire duration, the conventional method is inadequate to design the load capacity for appropriate fire safety. Therefore, it is essential to adopt a performance-based approach while designing structural elements' capacity for the desired fire resistance rating. The proposed technique of using non-dimensional parameters will effectively support predicting the load capacity for required fire resistance.

The fire-resistant requirements for reinforced concrete structures are generally established based on standard fire exposure conditions, which account for the fire growth phase. However, it is important to note that concrete structures can experience internal damage over time during the decay phase of fires, which can be quantitatively determined using the proposed non-dimensional parameter approach.

This paper aims to report a case study regarding the combined use of several non‐destructive techniques (NDTs) as a tool in the management of diagnosis and refurbishment of a damaged reinforced concrete building.

Four types of NDTs have been selected and carried out on the pillars of the building: visual inspection, electromagnetic rebar location, sonic test and rebound hammer test. The campaign has been planned and run in order to get the highest amount of reliable data about materials degradation and structural safety with limited costs and limited interference with the functionality of the building.

The diagnostic campaign highlighted the usefulness of the selected techniques in the diagnosis of the type and the amount of degradation, thus permitting a plan of refurbishments to be defined, and to get a realistic estimation of restoration costs.

NDTs' ability to specifically identify a type of damage may be viewed as a reliable tool in assessing and managing the structural life‐cycle cost.

The presented case study highlighted that NDTs are very likely to locate and quantify the damage of materials and buildings, so that they can be considered as one of the most important parts of health monitoring of civil structures and infrastructures.