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Deep soil mixing (DSM) columns as a retaining structure for deep excavations in soft soil areas has been widely used because, in addition to its low cost, it has fewer environmental hazards and no need of dewatering. However, due to its low tensile strength, this system usually requires a very thick wall cross section and is generally impractical for use as a retaining structure for very deep excavations. In an attempt to extend the use of DSM columns for deeper excavations, this paper introduces a so-called compound DSM retaining wall system that combines DSM columns with reinforced concrete bored piles. As shown in the paper, both the compressive strength of soil-cement mixtures and the bending moment capacity of concrete piles are developed to their full advantage in this hybrid soil-retaining system. The paper also presents the detail design methodology for the proposed compound DSM wall as a retaining structure for deep excavation. Finally, the benefits of this hybrid retaining system are further demonstrated through a case study completed in Shanghai, China. [ABSTRACT FROM AUTHOR]

Some toe-deck crack cases in China have been reported after about 10 years of service in suspension and beam bridge steel orthotropic decks with trough stiffeners. In this paper, a reference stress method used in design practice and a hot-spot stress method provided by the International Institute of Welding are used to investigate toe-deck fatigue of the newly built Taizhou Yangtze River Bridge. Shell and solid finite element models with different mesh sizes are compared. The hot spot at the weld toe and the point at the trough-deck intersection are discussed. One is a shell-model hot spot with no weld. The other is a solid-model hot spot with the weld. Hot-spot stress calculated with the shell model is larger than that with the solid model. Different extrapolation methods of hot-spot stress are discussed; stress calculated with the linear extrapolation method is almost the same as with the quadratic method. The stress of the joint under a moving unit wheel load is studied. Fatigue strengths against reference and hot-spot stresses are derived. Fatigue damages under the truck load, evaluated based on the reference stress method and the hot-spot stress method, are compared. [ABSTRACT FROM AUTHOR]

With China’s fast economic growth and entry into the World Trade Organization (WTO), more foreign architectural, engineering, and construction (AEC) firms are expected to venture into this huge and attractive market. This paper explores the important strategies to help foreign AEC firms clinch construction projects in China. Using a questionnaire survey approach complemented by in-depth interviews, it was found that firms need to pay more attention to the market and working conditions in China and to strengthen their own capabilities. To win projects in China, foreign AEC firms should also be able to offer project financing services. The findings are useful to foreign AEC firms because it may help them win projects in the Chinese construction industry. [ABSTRACT FROM AUTHOR]

As China becomes a member of the World Trade Organization, many international architectural, engineering, and construction (AEC) firms are undertaking or expected to undertake projects there. This study identifies the significant factors that contribute to the successful performance of projects undertaken by international AEC firms in China. Data were collected using structured questionnaires from foreign (non-Chinese) AEC firms that have completed projects in China. Personal interviews with 27 experts were also conducted to supplement and test the survey findings. The findings reveal that the variable that affects the most number of success measures is the AEC firm’s ability to understand the client’s requirement. Achieving this brings about good project quality performance and owner satisfaction. Furthermore, firms that have superior product or service quality would also achieve better project performance. The interviewees also exhorted the importance of having core competencies as a critical success factor for projects in China. Practitioners may use the findings to help them manage their projects in China, so as to achieve higher levels of success. [ABSTRACT FROM AUTHOR]

This case history presents an application of dynamic compaction in placement of a road embankment with a height of 41 m on the Yuncheng-Sanmenxia Expressway, Shanxi Province, China. The monitoring results during the compaction and the long period after compaction are analyzed and compared with those from compaction by rolling. It is obvious that dynamic compaction has such advantages as a high degree of compaction, a wide suitable range of placement water content (7–19%), and quick construction (over 4 m lift thickness) and can be applied in many high-fill engineering projects. In addition, application of a fabric-enclosed sand drain for treatment of an overwet soft foundation for a road embankment is also introduced. [ABSTRACT FROM AUTHOR]

Engineering problems with expansive soils in subgrades complicate highway construction in expansive soil areas of China. To research and solve the engineering problems, a Chinese research group carried out extensive research as part of the construction of a highway in Ningming Basin, a typical expansive soil area in China. The research on Ningming expansive soils is presented, including laboratory studies of soil properties, modified California bearing ratio tests for evaluating the bearing capacity, and wet compaction tests for obtaining the parameters to control field compaction when using expansive soils as embankment fill. The field investigations of slope failures also are introduced, including analysis of the investigations. New techniques for using expansive soils in embankments, and stabilizing cut slopes consisting of expansive soils, were developed and applied into the trial sections of the highway by the research group, based on their research and investigations. The measures proved successful and were used to solve the technical problems related to the NanYou Highway subgrade construction. The outcomes of the research also may prove useful in the construction of such projects as railway and hydraulic works. [ABSTRACT FROM AUTHOR]