Papers by Keyword: Full-Scale Experiment

Abstract: Oil country tubular goods (OCTG) are widely used in oil and gas industry. In order to increase joint efficiency of the oil country tubular goods, the process for upsetting their ends is applied. However, the weakness of this upsetting technology is a frequent defect creation on the inner surface of the final product. These imperfections are surface breakings that reduce the effective pipe wall thickness; they are detected close to the upset ends of the pipe. Computer simulation and full-scale experiment were used to study this defect nucleation. According to this research, the occurrence of defects is correlated with average pipe wall thickness, non-uniform wall thickness of the blank, heating mode and friction conditions. The results of full-scale experiment confirm the main conclusions made in the course of the finite element simulation. The research results define the interdependence of actual size of the blank and the operating tool calibration.

Abstract: The construction of objects of critical infrastructures such as a new roads, utility tunnels, communication networks, underground parks and other structures is associated by the way with generation of vibrations in the vicinity of the underground structures, and not only human lives can be lost but also extensive material damage can be expected due to technological and natural hazards based on vibrations. This paper presents the general governing equations for coupled thermo-hydromechanical process in the tunnel surrounds. Modeling and analysis of laminated composite cylinder applied for the objective analysis of shock wave propagation in the soils and possibilities to estimates of the tunnel structure damage.

Abstract: The research involved experimental testing of simple steel connections and components (structural 8.8 bolts) at elevated temperatures. High temperature tests on structural bolts demonstrated two modes of failure at elevated temperatures: bolt breakage and thread stripping. In order to prevent the thread stripping in a connection,the manufacturing process of bolts and nuts has been investigated and the ‘over tapping’ of nut threads to accommodate the (zinc) coating layer for corrosion resistance has been indentified as a primary reason resulting in this premature failure between bolts and nuts. Experimental tests on endplate connections revealed the ductility of these connections to decrease at high temperatures, which might hinder the development of catenary actions in fire if plastic hinges are attempted to be formed within the connection zones. Component-based modelling and finite element simulation have been utilized for investigation of the performance of these connections.

Abstract: The joints of corner are main connecting part of gabled frames, of which the performance directly affects the integral behavior of its structure subject to load. Some conclusions are given in the article. At the same time, the construction of joints also determines its features of the semi-rigid stiffness. In this article, numerical simulation and experimental research are conducted to investigate semi-rigid connection of corner joints in gabled frames with different height-thickness ratios of beam-column web, width-thickness ratios of flange, and height-width ratios in corner joints. The results reveal that in the gabled frames, the corner node with the inclined stiffening rib can improve the bearing capacity of the specimens. When the extraterritorial flange is tension, the erection of the inclined stiffening rib can prevent structural failure and improve effectually the ductility of the structure.

Abstract: In this paper, a new type of large span prestressed concrete integral roof was studied. The test uses full scale specimens, the roof’s span is 24 meters, the width is 2 meters, across the tallest is 3.6 meters. The different condition of roof structure properties is examined. Through experiment obtaines the deformation and the ultimate bearing capacity of the roof, the design is proved to be correct. Test results show that the roof system with one piece casting has enough bearing capacity and rigidity. Roof destruction presents brittleness nature, destroying position is in lower chord board near the end of place. This research conclusion provides a reference data for this type of roof of popularization and application.

Abstract: In order to clear constructional design of corner joint, it is necessary to further investigate mechanical property of corner joint in gabled frames. Through static test of comparing the panel zone with and without inclined stiffener. Some conclusions are given in the article. The load displacement curves show that the capacity of oblique nodes installed within stiffening rib components is enhanced i.e.40% more than those without stiffening rib nodes. The results reveal that in the gabled frames, the corner node with the inclined stiffening rib can improve the bearing capacity of the specimens. When the extraterritorial flange is tension, the erection of the inclined stiffening rib can prevent structural failure and improve effectually the ductility of the structure.

Abstract: At present, the structure of gabled frames is the most extensively-applied structure in the single-storey industrial building and long-span single-storey buildings. The joints of corner are main connecting part of gabled frames, of which the performance directly affects the integral behavior of its structure subject to load. At the same time, the construction of joints also determines its features of the semi-rigid stiffness. In this article, numerical simulation and experimental research are conducted to investigate semi-rigid connection of corner joints in gabled frames with different height-thickness ratios of beam-column web, width-thickness ratios of flange, and height-width ratios in corner joints. The three-folder-line moment-rotation relation model has been established and the expression concerning moment-rotation relation obtained.