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During the mid-1970s, there was a boom in the construction industry in Saudi Arabia. To meet the housing requirements, and to furnish the infrastructure needed for a growing industry, construction had to be carried out at a pace unprecedented in the country's history. In the absence of guidelines, concrete specifications from other industrialized countries were used. However, when the structures started to show signs of deterioration within a short fraction of their design life, it was realized that specifications developed for temperate conditions cannot be used in this region. Field and laboratory studies carried out at King Fahd University of Petroleum and Minerals at Dhahran, Saudi Arabia, showed that concrete in this region should not only be designed for strength, but also for durability. Since permeability is one of the most important properties that control the durability of concrete, much emphasis should be given to the production of dense and impermeable concrete. This paper reports the results of an investigation carried out on a number of reinforced concrete structures exposed to underground and seawater conditions that showed serious signs of deterioration within less than 10 years after construction. The paper recommends repair procedures for the damaged structures and future practices to extend their service life.

The quality of in situ concrete construction in developing countries is affected by a number of factors. These factors may include absence of national standards and codes of practice, use of approximate methods of analysis and design, substandard materials, poor construction practices, and inadequate quality control and inspection procedures. Defects and failures may occur due to these factors that may affect the useful life of a structure. This paper evaluates the seismic behavior of reinforced concrete buildings designed and constructed by following the usual procedures in Saudi Arabia. Behavior of typical reinforced concrete frames is investigated by using nonlinear time-history analysis and Takeda hysteresis model. The factors considered in the study include compressive strength of concrete, detailing of reinforcement, and size and orientation of columns in the frame. The results show that while the frames remained elastic when subjected to an earthquake of low intensity (0.09), they developed inelastic behavior exceeding the ductility capacity at some point when subjected to an earthquake of moderate intensity (0.24). It has been also found that the orientation of columns, particularly the interior ones, has a substantial effect on the building resistance to earthquakes. The compressive strength of concrete, through it has a crucial effect on the overall behavior and durability of a building, did not significantly affect the primary moment-curvature relationships of under-reinforced member sections considered in the study when its specified value was lowered by 20 percent. A critical study of reinforcement detailing shows clearly an urgent need for implementing a national code of practice for concrete buildings in Saudi Arabia.

Provides background information related to the feasibility of offshore concrete structures for the development of hydrocarbon resources in both newly developing regions of the world and in areas of existing offshore operations where concrete is currently not used. Bottom-founded structures, floating structures, and other more specialized structures are described and their market potential discussed. Three hundred offshore platforms are planned for Asia and Australia between 1990 and 1995; many of these could be built with concrete. The use of local concrete materials and labor to produce moderate strength concrete for these platforms is discussed. Special design and safety considerations are noted. The structures can be built in dry docks, on skidways, or on submersible barges. Portions of the structures can be precast concrete. All of these structures involve some marine operations. General cost considerations and life-cycle costs are discussed.

Reports on a nearly completed study begun in 1989 to improve the ductility of reinforced concrete members by mixing fibers with concrete. In this study, the bending test of fiber-mixed reinforced concrete beams made with two kinds of steel fiber and aramid fiber by reversal static loading has been done. From the test results obtained so far, it is shown that the ductility of fiber-mixed reinforced concrete beams is improved over that of normal reinforced concrete beams. It is calculated that the ductility factor of fiber-mixed reinforced concrete beams can be computed if the tensile strength and ultimate compressive strain are known.

Steel fiber reinforced concrete has been widely used in civil engineering. To promote further application of SFRC, there is a need to unify the design methods and construction techniques. Since 1988, an editorial committee for compiling a code for design and construction of steel fiber reinforced concrete structures has begun to work towards this purpose in China. Based on the results of extensive research activities and the experiences of practical application of SFRC, the draft of this code has been finished recently. The main contents of this code includes the requirements for the materials, basic design principles, ultimate limit state design, checking of the serviceability limit state, construction of SFRC, detailing of the SFRC structures with steel reinforcement, rules for design and construction of special structures, and design and construction for shotcrete SFRC. This paper will briefly introduce the main content of this code.