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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.

This paper presents an overview and discusses the applications of fibre reinforced polymer (FRP) bars as reinforcement in civil engineering structures. Following a discussion of the science underpinning their use, selected case studies where FRP reinforcement has been used are presented. The use of FRP reinforcement is rapidly gaining pace and may replace the traditional steel due to its enhanced properties and cost‐effectiveness. In addition, FRP reinforcement offers an effective solution to the problem of steel durability in aggressive environments and where the magnetic or electrical properties of steel are undesirable.

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.

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.

The aim of this article is to present a new, simple applicable method of inferring and assessing residential construction quality at an industry‐wide level.

Construction quality is measured using ratios of structural materials to production levels. Cement and reinforcing bar per 1,000m² of residential floor space are the metrics, especially appropriate in Taiwan as new dwelling units (virtually all apartments and row houses) and all of reinforced concrete. Complementary measurements of quality for labour and non‐structural construction material inputs were also made.

The structural input and complementary measures indicate that the quality of Taiwanese residential construction declines dramatically and consistently at higher production levels. The implication is that dwelling units from the 1990s construction boom are especially at risk.

The methods cannot be used to identify specific buildings at risk. The methods are difficult to apply in situations where construction methods and residential types are heterogeneous.

Construction quality can be monitored on a regular basis so industry‐wide steps can be taken if quality declines appear. The evidence is consistent with Taiwan's sub‐contractor network enabling rapid expansions and contractions at the expense of hidden quality failure.

This paper provides information that could lead to much firmer regulatory systems, hence has the potential to help save lives and property.

This study aims to identify systematically the factors that can often influence labour productivity directly and indirectly, to build a model that can evaluate the significance of these factors. The model can be used as a tool for assisting field construction mangers responsible for productivity.

The factors were first identified by undertaking a literature review. The scope and method for measuring labour productivity were then determined. The final analysis model was built through a statistical analysis conducted with the chosen factors.

The results of the analysis indicate that the work management component (e.g. the manager's abilities) and the work technique component (e.g. work continuity) have greater impact than the worker component (e.g. the workers' capability) and the work characteristic component (e.g. work difficulty).

This research focuses on the qualitative perspective of site managers on labour productivity. Although the process of translating qualitative opinions into quantitative data is a matter for debate, the result of this research, when compared to other quantitative studies, can be used to establish a strategy and an action plan for managing labour productivity.

Qualitative aspects that were considered to establish a labour productivity model can be evaluated by site construction managers. Despite the importance of these qualitative aspects, they have, by and large, been neglected, as models to date tend to consider more directly measurable quantitative factors. In particular, they can be used to develop a strategy for increasing labour productivity at the initial planning stage.

This research explores the differences between a subjective perception and the objective reality of labour productivity.

The objective of this paper is to investigate the effects and relative influence of: grid patterns; variability of foundation sizes; total surface area; and average surface area, on formwork labour productivity of isolated foundations.

To achieve this objective, a sufficiently large volume of productivity data were collected and analyzed at both levels; macro, and micro, using the linear regression method. As a result, the effects and relative influence of the investigated factors on formwork labour productivity are determined and quantified.

The findings show significant impacts of the buildability factors investigated on formwork labour productivity, and substantiate the importance of applying the rationalization and standardization concepts to the design stage of construction projects.

Further research into the effects of buildability factors on formwork, and other related trades of in situ reinforced concrete material, i.e. rebar fixing/installation and concreting, labour productivity, which are common to other structural elements and activities such as, grade/ground beams, columns, walls, beams, and slabs, is recommended, so that the related findings can ultimately be used to develop an automated “Buildability Design Support System” to formalize the buildability knowledge of reinforced concrete construction projects.

The outcomes of this research provide designers with feedback on how well their designs consider the requirements of buildability principles, and the tangible consequences of their decisions on labour productivity. In addition, practical recommendations deduced from the findings are presented, which upon implementation, can improve the buildability level of this activity, hence translate into higher labour efficiency and lower labour costs. On the other hand, the depicted patterns may provide guidance to construction managers for effective activity planning and efficient labour utilization.

The findings fill a gap in buildability knowledge and its influence on formwork labour productivity of an important, labour intensive, activity within the in situ reinforced concrete construction projects.

The construction industries at present are focusing on designing sustainable concrete with less carbon footprint. Considering this aspect, a Fibre-Reinforced Geopolymer Concrete (FGC) was developed with 8 and 10 molarities (M). At elevated temperatures, concrete experiences deterioration of its mechanical properties which is in some cases associated with spalling, leading to the building collapse.

In this study, six geopolymer-based mix proportions are prepared with crimped steel fibre (SF), polypropylene fibre (PF), basalt fibre (BF), a hybrid mixture consisting of (SF + PF), a hybrid mixture with (SF + BF), and a reference specimen (without fibres). After temperature exposure, ultrasonic pulse velocity, physical characteristics of damaged concrete, loss of compressive strength (CS), split tensile strength (TS), and flexural strength (FS) of concrete are assessed. A polynomial relationship is developed between residual strength properties of concrete, and it showed a good agreement.

The test results concluded that concrete with BF showed a lower loss in CS after 925 °C (i.e. 60 min of heating) temperature exposure. In the case of TS, and FS, the concrete with SF had lesser loss in strength. After 986 °C and 1029 °C exposure, concrete with the hybrid combination (SF + BF) showed lower strength deterioration in CS, TS, and FS as compared to concrete with PF and SF + PF. The rate of reduction in strength is similar to that of GC-BF in CS, GC-SF in TS and FS.

Performance evaluation under fire exposure is necessary for FGC. In this study, we provided the mechanical behaviour and physical properties of SF, PF, and BF-based geopolymer concrete exposed to high temperatures, which were evaluated according to ISO standards. In addition, micro-structural behaviour and linear polynomials are observed.

The current study mainly focuses on the effect of varying diameter recycled steel fibers (RSF) on mechanical properties of concrete prepared with 25 and 50% of recycled coarse aggregate (RCA) as well as 100% natural aggregate (NA). Two types of RSF with 0.84 mm and 1.24 mm diameter having 30 mm length were incorporated into normal and recycled aggregate concrete (RAC).

The fresh behavior, compressive, splitting tensile, flexural strengths and modulus of elasticity of all the mixes were investigated to evaluate the mechanical properties of RACs. In addition, specimen crack and testing co-relation were analyzed to evaluate fiber response in the RAC.

According to the experimental results, it was observed that mechanical properties decreased with the increment replacement of NA by RCA. However, the RSF greatly improves the mechanical properties of both normal concrete and RACs. Moreover, mixes containing 1.24 mm diameter RSF had a more significant positive impact on mechanical properties than mixes containing 0.84 mm diameter RSF. The 0.84 mm and 1.24 mm RSF addition improved the mixes' compressive, splitting tensile and flexural strength by 10%–19%, 19%–30% and 3%–11%, respectively when compared to the null fiber mix. Therefore, based on the mechanical properties, the 1.24 mm diameter of RSF with 25% replacement of RCA was obtained as an optimum solution in terms of performance improvement, environmental benefit and economic cost.

The practice of RCA in construction is a long-term strategy for reducing natural resource extraction and the negative ecological impact of waste concrete.

This is the first study on the effects of varying size (0.84 mm and 1.24 mm diameter) RSF on the mechanical properties of RAC. Additionally, varying sizes of RSF and silica fume added a new dimension to the RAC.

The purpose of this paper is to investigate the potential design advantage in terms of resistance factors for normal weight concrete beams containing moderate-dose randomly dispersed short fibers and reinforced with glass fiber reinforced polymer (GFRP) bars.

An analytical model based on the current code specifications is used to calculate the moment capacity of over-reinforced sections. The vast majority of the considered beams are over-reinforced, compression-controlled. The data of the fiber-reinforced concrete (FRC) reinforced with GFRP bars are collected from three published research studies which are based on experimentally tested results. Three different types of short fibers with four volume fractions are considered. Probabilistic model is established to conduct reliability-based calibration using Monte-Carlo Simulation. Limit state function, relevant load and resistance random variables are identified, and adequate statistical parameters are selected. Target reliability index consistent with the one used to develop current design code specifications is used.

Reliability analysis and calibration process are carried out with the intention of estimating the flexural resistance factors for FRC beams reinforced with GFRP bars.

The predicted flexural resistance factors ranged from 0.72 to 0.95, giving the resistance factors the potential to be increased above the currently specified value of 0.65 for compression-controlled members reinforced with FRP bars.