Economic Composite Constructions for Bridges: Construction Methods Implementing Composite Dowel Strips

A composite bridge type incorporating corrugated steel webs fits beautifully into the surroundings, as Dole bridge or Maupre viaduct near Charolles do. The weight of the structure and the clear flow of forces in it give designers the possibility to improve structural details and construction methods in order to meet various environmental needs. The innovation of creating a structural element by folding a flat plate into a corrugated shape took place in France. A folded plate is compliant in compression while exhibiting high in-plane shear resistance. This function is ideal in order to enhance the moment capacity of prestressed box girder bridges. The assembly of corrugated steel webs into box girders and the anchorage of ­external prestressing tendons required novel connecting techniques. Extradosed prestressing enhances the moment capacity of bridge girders and lightens the structure. Hence, extradosed prestressing and corrugated steel webs make an ideal match. Both cantilever construction and incremental launching have been used. More than 100 bridges with corrugated steel webs have been built in Japan in one and a half decades. Durability was designed with care, in particular the durability of external prestressing tendons and interfaces between corrugated steel webs and concrete. A guide to maintain durability is now being prepared in Japan by the engineering association and one of the road companies. National and local government and the autonomous public authority for highway construction encouraged innovative design and construction methods. Their guidance to verify performance by tests gave industry confidence in reliability and helped it to develop progressively challenging projects. After the dissolution of JH (Japan Highway Public Corporation) in 2005, efforts to archive technical data are being made by three regional road ­companies, West-, Central- and East- NEXCO, their research institute, the ­engineering association, prestressed concrete contractors and an industry group. Innovation in bridge construction in Japan has been prompted by the progressive management methods of the public autonomous authority, which has 50 years of experience in this field. After JH was divided into the three NEXCOs, new schemes to encourage innovation were looked for. One attempt to that end is the creation of an innovative design guide. The new design guide yet to come may urge designers to create structures for high performance and specific targets.

The prestressed concrete girder with corrugated steel webs is one of the most promising steel–concrete hybrid structures applied to highway and railway bridges, owing to its excellent mechanical properties and efficient material utilisation. Composite bridges with corrugated steel webs (CBCSWs) have undergone rapid development in China since 2005, resulting in remarkable technical progress in many aspects. A state-of-the-art review of CBCSWs in China is presented. Based on data collected for over 90 CBCSWs built in China during the years 2005–2018, characteristics relating to bridge span, structural type and construction methods are comprehensively analysed. Some mechanical issues regarding the design and construction of typical CBCSWs are elaborated to understand fully their structural performance and promote their development. Furthermore, a few representative CBCSWs are expounded in relation to their innovative structural design and construction techniques; their respective characteristics are highlighted. Finally, several conclusions are drawn and future research directions are predicted: the CBCSW is a competitive bridge solution when 80–200 m main spans are required; advanced materials, innovative structure types and advanced construction methods making good use of corrugated steel web are the source of its development. The experiences in this study can serve as a useful base for constructing more excellent and impressive CBCSWs.

Objectives/Scope The project was a 2km, electrically heat-traced, subsea pipe-in-pipe (PIP) system for transportation of a bitumen-like material across a shipping channel. Due to the viscosity of the bitumen, it must be transported at a minimum of 160°C; has a normal pipeline operating temperature of 200°C; and a design temperature is 228°C. Methods, Procedures, Process Due to the high operating temperature, pre-stressing and backfilling the PIP was required to lock in stresses at an intermediate pre-stressing temperature. The electrical heat-trace wires (installed to heat up the inner pipe and prevent setting of the bitumen during cooldowns) were used to achieve this pre-stressing during the fabrication process. The heating schedule causes high stress levels and require advanced engineering analyses to model the behaviour of the inner and outer pipe during the fabrication, installation, pre-stressing, and operation. The complex loading history of the inner pipe and the expansion spools was included in the global 3D, finite element (FE) models that were used to validate the pipeline profile, backfilling, pre-stressing temperature, and sequence of operations. Results, Observations, Conclusions The complex buckling behaviour of the inner pipe is presented and shown to be within DNV GL OS-F- 101 code limits. The end expansion during the various stages of pre-stressing is presented and compared to observed behaviour. The loads and stresses in the bulkheads are presented and shown to be acceptable. The analysis demonstrates that the pipeline system can be safely installed and operated up to the maximum design temperature of 228°C. Novel/Additive Information The project used pre-stressing by heating the inner pipe to an intermediate temperature before coupling the inner pipe to the outer pipe. The purpose of the pre-stressing was to manage the high axial stresses making it feasible to achieve the high design temperature of 228°C. Pre-expanding of the expansion spools at either end of the subsea pipelines was also used due to the space limitations. Innovative engineering analysis and construction methods were used to ensure the integrity of the inner pipe during the pre-stressing process and operation.

Constructability issues still exist during field operations and once in the field, constructors can still reap constructability benefits from their actions alone. The objective of this paper is to explore the ways in which construction knowledge and experience can enhance constructability during field operations. While previous constructability research efforts have been primarily directed toward owners and designers, this research is primarily directed toward constructor organizations. The employed research method was an iterative process of issue identification, literature search, site interviews, and analysis. Ultimately, a single prime concept for field operations constructability was concluded: Constructability is enhanced when innovative construction methods are utilized. Innovative construction methods may involve innovations related to sequencing of field tasks, temporary construction materials/systems, hand tools, construction equipment, constructor‐optional preassembly, temporary facilities directly supportive of field methods, or post‐bid constructor preferences. Beyond addressing each of these in detail, in this document “innovative” construction is also analyzed in terms of related prompters or drivers. The linkage between field operations constructability and construction technology is also addressed.

The research mainly discusses the correlation between the effect of technological evolution and the environmental aspects on architecture. The research depends on data analysis of theoretical study which carried out to explain the features of this effect. The environment could be classified to two major elements: the natural environment and built environment. Through ages, both natural and built environment are responsible for formulation of cultural and religion identity of any civilization which identifies it and achieves respect and appreciation from various civilization. On other hand, the development of societies requires paying attention and keeping up with technological evolution through ages. Technological evolution provides new tools and techniques for many fields in societies especially architecture as many features are affected by it such as: the evolution of design process, building materials, structural systems, and construction methods. As well, the architectural thinking is developed through the implementation of new digital design methodologies, new building materials configuration, and innovative construction methods. This development formulates a contemporary architecture which differs in its concept and applications from any previous architecture concepts appeared in all ages before information technology age. Recently, a huge confusion caused by approaches which discussed and presented by theorists to achieve the balance between the technological capabilities and environment determinants to submit an objective architecture which meet the need of activities applied in and do not care about the form without the content. The research offers a methodology to measure the extent to which contemporary architecture is connected with the place. The proposed methodology depends on the different dissertations that call for the establishment of a balance between originality and contemporary and is used to evaluate the architectural practices which are connected with the place. The practical study relies on applying the central axis of new Cairo as a case study to follow the Egyptian contemporary practices which are connected to the place.

Three-Dimensional FE Modelling of Simply-Supported and Continuous Composite Steel-Concrete Beams

Since the fifties, composite construction in steel bridges has been used in simple as well as in continuous structures. Composite construction incorporates the concrete deck with the top flange of the supporting rolled beams or welded plate girders. The final result consists of the two components from different materials acting as a unit. The composite action can be accomplished by mechanical bond between the flange and deck in the form of welded channels, studs, or other devices. Either shored or unshored construction can be specified. Composite construction for highway bridge design is most economical for spans in the range of 40-50 ft. and longer. The increase in the moment of inertia of the composite section helps in reducing deflection due to live load and impact. For shorter spans, the saving in steel weight does not usually pay for the additional weight of the shear connections and labor involved. Composite steel girder bridges in the United States are usually designed using the Load Factor Design procedure of AASHTOs Standard Specifications for Highway Bridges. Current AASHTO allows the bending moment capacity of compact sections in positive bending to be based on the full plastic moment. The moment capacity at first yield is used, however, for non-compact sections. In most practical cases, the full plastic moment of composite sections is significantly larger than the yield moment.

This paper evaluates the current conditions of Ugandan low-income tropical housing with a focus on construction methods and materials in order to identify the key areas for improvement. Literature review, site visits and photographic surveys are carried out to collect relevant information on prevailing construction methods/materials and on their environmental impacts in rural areas. Low quality, high waste, and energy intensive production methods, as well as excessive soil extraction and deforestation, are identified as the main environmental damage of the current construction methods and materials. The embodied energy is highlighted as the key area which should be addressed to reduce the CO2 emissions of low-income tropical housing. The results indicate that the embodied energy of fired bricks in Uganda is up to 5.7 times more than general clay bricks. Concrete walling is identified as a much more environmentally friendly construction method compared to brick walling in East African countries. Improving fuel efficiency and moulding systems, increasing access to renewable energy sources, raising public awareness, educating local manufacturers and artisans, and gradual long-term introduction of innovative construction methods and materials which are adapted to local needs and conditions are some of the recommended actions to improve the current conditions.

PurposeThe purpose of this paper is to investigate the role of exogenous factors in the strategic performance of construction companies. A conceptual model is proposed where strategic performance is influenced by a two‐dimensional construct composed of market conditions and strategic alliances.Design/methodology/approachA questionnaire survey was administered to 73 construction companies. Structural equation modeling was used to analyze the data and test the hypothesis that strategic performance is impacted by exogenous factors. The individual constructs used in the study passed the internal reliability test, all factor loadings were statistically significant at α=0.05, all goodness of fit indices consistently indicated a good fit, and the hypothesized path coefficient was large and significant at α=0.05.FindingsThe hypothesis was supported by the data and analysis. Indeed, macro‐economic, political, legal, socio‐cultural conditions and the level of competition and demand are expected to impact differentiation strategies, and market/project/partner selection strategies. The quality of the relationships with government agencies and clients is expected to influence client/project/market selection strategies, while the quality of the relationships with labor unions may affect the ability to differentiate by using innovative construction methods, materials and equipment.Research limitations/implicationsIt is likely that endogenous factors such as company resources, capabilities and project management competencies also impact strategic performance. But the study is confined only to the exogenous factors of market conditions and strategic alliances.Practical implicationsThe findings of the study benefit construction company executives in that they make the executives more cognizant of the market environment and they draw the executives' attention to the importance of alliances with other parties. While market conditions are beyond the control of construction executives, relationships with other parties are somewhat within their sphere of influence.Originality/valueOnly a few studies have ever investigated non‐financial measures to assess the effectiveness of company strategies. Also, exogenous factors which are unavoidable in a project environment were also rarely discussed in the construction management literature. The originality of this study is that it uses non‐financial measures to assess the effects of exogenous factors on strategic performance.

Chapter 9 - Materials

The construction industry is one of the key sectors of the economy, which largely determines the level of development of infrastructure, the social sphere and the industrial potential of the state. In the context of globalization, rapid technological progress and growing environmental challenges, the relevance of innovative activity in the construction sector is constantly growing. The introduction of new technologies, materials, methods of design and management of construction processes is an integral part of the sustainable development of the industry, which allows to improve the quality, safety, efficiency and environmental friendliness of construction. The conceptual principles of innovative activity cover comprehensive approaches to the creation, implementation and use of new technologies and materials that contribute to the optimization of construction processes. An important task is to harmonize scientific and technological progress with economic and environmental aspects. The introduction of modern digital technologies, such as BIM (Building Information Modeling), automation of construction processes, the use of artificial intelligence and "smart" construction solutions, significantly changes traditional approaches to the design, construction and operation of facilities. The theoretical foundations of innovation in the construction industry are based on an interdisciplinary approach that combines engineering, economic, managerial and environmental aspects. Analysis of innovation processes allows us to identify key success factors, including financial support, research and development, legal regulation, international experience and professional training. Improving the regulatory framework and stimulating investment in scientific and technical development are important conditions for the formation of a favorable environment for innovation in construction. Thus, the study of the conceptual foundations and theoretical foundations of innovation in the modern construction industry is of strategic importance. The introduction of innovations not only increases the competitiveness of the construction industry, but also contributes to the development of sustainable construction, which meets global trends and requirements of modern society.

Composite steel-concrete construction is widely used throughout the world for building and bridge applications. This paper focuses on the service behaviour of composite and post-tensioned composite floor slabs and how these are influenced by shrinkage effects. Research carried out in recent years has highlighted the occurrence of a non-uniform shrinkage profile that occurs through the thickness of a composite slab due to the inability of the concrete to dry from its underside because of the presence of the profiled steel sheeting. Two approaches are considered in this paper for the evaluation of the non-uniform shrinkage profile, one based on a simplified approach and one relying on a hygro-thermo-chemical-mechanical model. The deflection predictions produced by the non-uniform shrinkage profiles (obtained with the two approaches) are then calculated with a design procedure available in the literature. In the first part of the paper, the main factors influencing the composite shrinkage response are introduced, followed by the main features of the design model used for the deflection predictions and of the two approaches presented for the evaluation of the non-uniform shrinkage profiles. The adequacy of the two approaches is then evaluated by comparing the calculated long-term deflections with those measured experimentally from long-term tests carried out on selected post-tensioned composite slab samples that have been reported in the literature .

Chapter 10 - Field Applications

Experimental investigation of connection details for precast deck panels on concrete girders in composite deck construction

The efficient detection of lead ions (Pb2⁺) is significant for environmental protection and public health. Electrochemical detection has emerged as one of the most promising technologies due to its low detection limits, high sensitivity, and cost-effectiveness. However, significant challenges remain, including issues related to sensitivity, selectivity, interference, and the stability of electrode materials. This review explores recent advancements in the field, focusing on integrating novel catalytic materials and innovative sensor construction methods. Particular emphasis is placed on enhancing the electrocatalytic redox processes on sensor surfaces using advanced nanomaterials such as MXenes, ferrite-based nanomaterials, carbon nanomaterials, and metal–organic frameworks (MOFs). Additionally, the role of biomaterials and enzymes in improving electrochemical sensors’ selectivity and anti-interference capabilities is discussed. Despite the impressive low detection limits achieved, real-world applications present additional challenges due to the complex composition of environmental samples. The review concludes with future perspectives on overcoming these challenges by leveraging the unique properties of catalytic materials to develop more effective and reliable electrochemical sensors for trace Pb2⁺ detection.