A stress‐strain model is developed for concrete subjected to uniaxial compressive loading and confined by transverse reinforcement. The concrete section may contain any general type of confining steel: either spiral or circular hoops; or rectangular hoops with or without supplementary cross ties. These cross ties can have either equal or unequal confining stresses along each of the transverse axes. A single equation is used for the stress‐strain equation. The model allows for cyclic loading and includes the effect of strain rate. The influence of various types of confinement is taken into account by defining an effective lateral confining stress, which is dependent on the configuration of the transverse and longitudinal reinforcement. An energy balance approach is used to predict the longitudinal compressive strain in the concrete corresponding to first fracture of the transverse reinforcement by equating the strain energy capacity of the transverse reinforcement to the strain energy stored in the concret...

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Theoretical stress strain model for confined concrete

General stress–strain relationship for concrete at elevated temperatures

Transport infrastructure development and changing spatial accessibility in the Greater Pearl River Delta, China, 1990–2020

Dynamic impact of moving vehicles on bridges is an important and long-standing issue in the design and evaluation of bridges and has received much attention from researchers and engineers The use of the dynamic impact factor (IM) to account for the impact effect of vehicles has been widely accepted in bridge engineering Accurate evaluation of the IM will lead to safe and economical designs of new bridges and provide valuable information for condition assessment and management of existing bridges Nevertheless, agreement on the evaluation of IMs is yet to be reached Numerous studies have shown that the evaluation of the IM is a difficult task because it is influenced by a large number of parameters and uncertainties As a result, different forms and values of IMs are specified by different bridge design codes and this disagreement has been debated in many studies in the past few decades Furthermore, some field tests observed that the IMs in design codes are overestimated while many other field 

State-of-the-Art Review of Dynamic Impact Factors of Highway Bridges

Choosing the most suitable superstructure is vital for the success of a small to medium-span highway bridge design. Numerous attributes must be considered and evaluated in terms of many different conflicting criteria in the conceptual design of a bridge, leading to a large set of subjective or ambiguous data. Furthermore, integrating experts' knowledge and experiences to make appropriate decisions is a commonly used method. In order to solve this problem, project managers and design engineers need to evaluate their initiative designs carefully and make accurate decisions. For this reason, a systematic decision process for selecting the best design idea by means of a novel integrated optimization-based methodology is proposed. In the first phase, Quality Function Deployment (QFD) is employed for translating the project requirements into design requirements. In the second phase, Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) is utilized to select the best superstructure as an alternative, based on the weighted criteria achieved from the first phase. In this study the rating values regarding to each alternative and criteria throughout the phases are described in a fuzzy environment by means of linguistic variables. Finally, a case study is provided to illustrate the implementation process of the integrated methodology for bridge superstructure design. For this purpose, an expert team has been formed to collect and verify the expectations of the project, which located in Tehran, Iran. The results demonstrated that the proposed methodology could be successfully applied in the highway bridge projects as a useful tool to facilitate decision making.

A fuzzy integrated methodology for evaluating conceptual bridge design

The Bridge Engineering Handbook is presented in seven sections: 1. Fundamentals; 2. Superstructure Design; 3. Substructure Design; 4. Seismic Design; 5. Construction and Maintenance; 6. Special Topics (including Weigh-in-Motion Measurement of Trucks on Bridges, Impact Effect of Moving Vehicles, and Wind Effects on Long-span Bridges); 7. Worldwide Practice (including chapters on China, Europe, Japan, Russia, and the USA). Rehabilitation, retrofit and maintenance of bridges, along with a section on soil-foundation-structure interaction is included.

Bridge Engineering Handbook

Mitigating the effects of earthquakes is crucial to bridge design. With chapters culled from the best-selling Bridge Engineering Handbook, this volume sets forth the principles and applications of seismic design, from the necessary geotechnical and dynamic analysis background to seismic isolation and energy dissipation, active control, and retrofit

Bridge Engineering : Seismic Design

Bridge engineering handbook : construction and maintenance

Bridge Engineering Handbook : Superstructure Design

Bridges are very important elements in a modern transportation system. Recent earthquakes, particularly the 1980 Loma Priets and the 1994 Northridge Earthquakes in California, the 1995 Hyogo-Ken Nanbu Earthquake in Japan, the 1999 JiJi Earthquake in Taiwan, and the 1999 Kocaeli Earthquake in Turkey, have caused collapse of, or sever damage to, a number of major bridges. Since the 1989 Loma Prieta Earthquake, extensive research has been done on seismic design and retrofit of bridges in Japan and the United States, especially in California. This chapter will discuss the seismic bridge design philosophies and conceptual design in general as well as discuss U.S. seismic design practice to illustrate the process. The chapter will also briefly presents seismic design practice in Japan.

Lian Duan

Papers

Bridge Engineering Handbook

Bridge Engineering : Seismic Design

Bridge engineering handbook : construction and maintenance

Bridge Engineering Handbook : Superstructure Design

Seismic Design of Bridges