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Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Segmental lining elements – Full scale test considering optimized force transmission During excavation of a tunnel by means of shield tunnel boring machines, segmental lining elements provide stability for the excavated cavity and act as internal liner. Therefore, it is essential to have knowledge about their structural load‐bearing capacity and performance under specific stress situations. After installation, the segmental lining element is exposed to a variation of loads from the surrounding rock mass. For the full‐scale tests performed at the Montanuniversität Leoben, a combined force application was used to simulate a realistic loading of a segmental lining element. To simulate the normal forces resulting from the circular load carrying behavior in the cross‐section, a force is applied in the horizontal direction at the beginning of the test. After reaching this load value, the vertical force is increased until failure of the element occurs, while the horizontal load is kept constant. Due to the specific segment geometry, a force in the vertical direction is also necessary simultaneously during the loading of the horizontal force in order to prevent buckling of the test specimen. The required force can be determined using a numerical simulation, or as an alternative, the vertical force can be determined in a simplified form by means of conventional static calculation, which is demonstrated in the present paper. Different considerations are shown and compared. [ABSTRACT FROM AUTHOR]

The seamless asphalt plug expansion joint integrates a traditional asphalt plug joint (APJ) with an overlying continuous asphalt concrete layer, preventing block failure of the asphalt plug joint and enhancing driving comfort. However, typical damages such as fatigue cracking, rutting, and permanent deformation often occur in the upper asphalt layer. This is attributed to the inadequate stiffness of the lower joint plug mastic, particularly under high temperatures and heavy loads. To extend the service life of asphalt plug expansion joints under such conditions and enhance their durability, efforts were made to bolster the performance of the lower asphalt plug joint mixture and improve anti-rutting performance. This study involved: (1) Qualifying APJ mixture requirements under high temperature and heavy load by focusing on two critical material properties: good rutting resistance and permanent deformation resistance. High temperature rheological properties of these binders were examined through temperature scanning tests and multi-stress creep recovery tests (MSCR). (2) Exploring the impact of binder-aggregate ratios and specimen molding methods (standard compaction, paving vibration and pre-mixing) on the bonding strength and rutting resistance of the APJ mixture. This analysis was conducted using pull-off tests and dynamic stability tests. (3) Development of a novel APJ featuring dowel bars to enhance vertical deflection resistance and joint horizontal movement. Comprehensive laboratory tests showcased the modified joint structure's resilience after numerous test cycles, demonstrating exceptional resistance to bending and vertical deformation. The significant findings from this research provide valuable insights for optimal material selection, appropriate joint design, and installation guidelines for seamless asphalt plug expansion joints.

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper considers the fire risk associated with luggage in trains from an experimental point of view. After a review of existing data, it was decided to test medium isolated suitcases, large isolated suitcases, two medium and one large suitcases in a rack, and two medium and one large suitcases in a confined rack, representative of luggage stacked next to the entrance doors of coaches in high-speed trains. Heat release rates were estimated by three methods: mass loss measurement, dilution calorimetry and oxygen consumption calorimetry. Measured peak heat release rates are of order 250 kW for medium size suitcases and 400 kW for large suitcase. The sum of two medium and one large suitcase would therefore be in the order of 900 kW. However, rack tests with two medium and one large suitcase gave values in the order of 1300 kW for an open rack and 2100 kW for a confined rack. This shows a strong effect of rack geometry and confinement. The concentrations of carbon monoxide and carbon dioxide are also measured, as is the total amount of hydrogen cyanide released in each test. An empirical fire curve is proposed taking into account the effect of confinement. [ABSTRACT FROM AUTHOR]

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes two full-scale tests carried out on two natural stone masonry walls subjected to fire loading, the first one was thermally loaded only (exposed to fire during 120 min without failure, then a natural cooling phase was observed) while the second one was thermally and mechanically loaded (exposed to fire and loaded up to failure with a compressive force at its bottom end). The experimental results showed that the thermal bowing was greatly affected by the in-plane mechanical loading. A water vaporization plateau at about 100 °C has also been observed, showing the influence of the hydric phenomena on the temperature distribution across the wall thickness. Analysis of cracking and failure of the walls showed that crack initiated in the vertical joints and propagated vertically through the blocks, which is quite typical for masonry in compression. Furthermore, the observed fire behaviour of natural stone masonry walls has been compared to the fire behaviour of newer, manufactured materials such as hollow bricks, concrete blocks or reinforced concrete walls. [ABSTRACT FROM AUTHOR]

This paper is prepared to report the engineering practice by a Chinese railcar manufacture in a railcar design process for a Metro system in U.S. The fire resistance of rail car floor systems is considered as one of the important fire protection features on the railcars operated in U.S., which provides fire separation between the equipment installed under the floor and the passengers insider railcar. In this study, a pragmatic approach was developed to numerically evaluate the fire resistance of rail car floor assemblies and provide insights for necessary design modifications. Finite element analysis (FEA) was applied to assess the fire resistance performance of a rail car floor assembly designed for a metro railway system in the U.S. An optimization algorithm was applied to obtain the thermal properties of intumescent coating. FEA analysis results were applied to assist the design modifications so that the floor assembly successfully satisfies the current requirement and passes the ASTM E119 fire resistance test. The FEA modeling details and heat transfer analysis results are presented. It is also shown that the model predictions agree conservatively well with the full-scale fire resistance test data.

Stainless steel is increasingly used in structural applications but there is still significant lack of experimental evidence on the moment-rotation (M-) behaviour of moment resisting beam-to-column connections. The current paper presents experimental test results obtained from full scale tests conducted on three widely used connection types i.e., double web angle (DWA), top seat angle (TSA) and top seat with double web angle (TS-DWA) connection. Considered beam, column and angle sections were fabricated using austenitic stainless steel plates and M20 high strength bolts were used for connection assembly. M- curves for all connections were carefully recorded and were used to determine initial stiffness (Ki) and moment capacity (M20mrad) for each of the connections. Eurocode 3 guidelines were used to check the classification i.e., whether or not the connections were semi-rigid in nature. Although the considered DWA connection failed to achieve partial-strength, both TSA and TS-DWA connections showed obvious semi-rigid nature despite the connection capacities were limited by bolts. In addition, extensive ductility of stainless steel ensured that all three connection types achieved a minimum connection rotation of 30 mrad, which is specified by FEMA as a requirement for earthquake design of ordinary moment frames.

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A full-scale reinforced subgrade for railways (RSR) was constructed, and repetitive and static load tests were performed to analyze the deformation characteristics of reinforced rigid walls with short reinforcements for railway subgrades that require strict displacement restrictions. Load test results were obtained for four sections, in which the reinforcement arrangement (vertical spacing and length) and wall-reinforcement connection method were applied differently, and the behavior of the reinforced rigid wall was observed according to each parameter. A repetitive load of 500 kPa and a static load of 1000 kPa were applied to the outside of the reinforcement area to evaluate the behavior of the subgrade when utilizing short reinforcement. The test results confirmed the reduction of the settlement and horizontal displacement of the wall, owing to the restraining effect of the short reinforcement and rigid wall. In addition, it was observed that the greater the applied load, the greater the influence of the reinforcement on the behavior of the subgrade; this pattern was more marked in loads above the yield of soil. [ABSTRACT FROM AUTHOR]

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Connections play an important role in the response of steel moment resisting frames to seismic loading. Prequalified rigid connections are applicable to I-shaped or box columns. In I-shape beam to concrete-filled tube (CFT) column connections, continuity and doubler plates cannot be added to the column. Various details have been proposed to address this issue, many of which are not constructionally convenient to implement. The aim of this study is to present a simple and suitable detailing for I-shape beam to concrete-filled tube column connections. To that end, six full-scale experimental samples were built and subjected to cyclic quasi-static loading. In the samples, stiffened and un-stiffened channel links were used to connect the beam to the column. In each sample, the stiffeners were installed on a different position on the channel link. The results showed that compared to the connection in which the beam is directly connected to the column, using the stiffened channel link with stiffeners along the beam's flange increases the strength and ductility of the connection by 12% and 72%, respectively. Considering their desirable performance and easy implementation, these connections can be considered as a suitable detailing for I-shape beam to CFT column connections in seismic regions. [ABSTRACT FROM AUTHOR]

Recent experiments conducted at the NIST examined steel-concrete composite floor systems designed per U.S. practice under standard fire. The first experiment designed per prescriptive provisions for a 2-h fire rating with 60 mm2/m of reinforcement, developed a central breach integrity failure after approximately 1 h of exposure. The second and third experiments, designed with 230 mm2/m of reinforcement, with the third one omitting the fire protection on the central steel beam, showed no failure within 2 h. This paper describes a numerical investigation to gain further insights into the fire behavior of the composite systems tested in these experiments. Nonlinear finite element models were validated against the tests. Simulation of the first test shows concrete damage and rebar fracture in the hogging moment area corresponding with the cracks observed experimentally. Simulation of the third test captures the development of tensile membrane action, confirming the redistribution from the unprotected secondary steel member to the floor reinforcing steel. A sensitivity analysis allows identifying the minimum reinforcement steel for protected and unprotected central beams configurations. The results can support improvements of the fire requirements in the U.S. codes as well as application of performance-based structural fire design for composite structures. [ABSTRACT FROM AUTHOR]

The present paper deals with complex material properties of DN 300 pipeline from the section Olesna - Barchov. The work was aimed at experimental verification of the effect of welded-on cover patches on the pipeline integrity. Two types of welded-on cover patches were evaluated. In the first case, just a single patch - steel plate was welded into the pipeline wall, replacing the damaged area. A lack of root fusion was found by means of the NDT. In the second case, the primary patch welded into the wall was covered by an auxiliary patch welded over the first one. No imperfection of the weld integrity was shown in the second case. The experimental programme contained an evaluation of the resistance of the repaired section to 10 000 pressure cycles induced by the inner water pressure at R = 0 cycle load asymmetry and maximum pressure of 6.3 MPa. The effect of these repairs on the limit state of the pipeline was verified by means of hydrostatic burst test. The tests comprised the evaluation of fracture surface morphology.

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes a full-scale natural fire test to investigate the collapse behaviour of a single storey cold-formed steel (CFS) building, designed to behave in a specified way in a severe fire, with roof venting and partial wall collapse. The test building had a span of 8 m, height-to-eaves of 2.15 m, and length of 10 m. The walls of the CFS building were constructed from cantilever 'stud & track' panels, with stud spacing of 0.6 m. The roof of the building comprised CFS trusses pinned to the wall connection plates at the top. In this fire test, walls on two adjacent sides were lined internally with fire resistant lining to achieve a structural fire resistance of 30 min (R30) and the calculated fire load was provided to generate a structural fire severity of 30 min, taking into account roof venting. Thus the two protected walls were expected to remain vertical throughout the fire; the roof was expected to collapse first, followed by pulling in of the unprotected walls. The CFS cantilever wall/roof truss system collapsed with an inwards asymmetrical collapse mechanism at a truss temperature of 622.5 °C, with collapse being due to member buckling of the non-fire rated wall rather than failure of the screws or joints. A non-linear finite-element (FE) model is then described. The collapse temperature predicted using the FE was 628.2 °C, with a deformed shape similar to that observed in the fire test. The FE model has matched the experimental behaviour, thus making this model useful in understanding and predicting the behaviour of CFS cantilever wall/truss system in severe fire conditions. • A full-scale natural fire test on a single-storey building constructed entirely of cold-formed steel (CFS) is described. • The walls on two adjacent sides were lined internally with fire resistant lining to achieve a structural fire resistance of 30 min (R30). • The CFS cantilever wall/truss system collapsed inward asymmetrically at 622.5 °C and, at a time of 21 min 30 s. • A layer of 15 mm gypsum board protected the CFS stud in the South and West walls from 45% rise in temperature and a time delay of 46%. • A non-linear finite-element model is described which predicted the failure temparature as 628.2 °C, with a deformed shape similar to the test results. [ABSTRACT FROM AUTHOR]

A full-scale reinforced subgrade for railways (RSR) was constructed, and repetitive and static load tests were performed to analyze the deformation characteristics of reinforced rigid walls with short reinforcements for railway subgrades that require strict displacement restrictions. Load test results were obtained for four sections, in which the reinforcement arrangement (vertical spacing and length) and wall-reinforcement connection method were applied differently, and the behavior of the reinforced rigid wall was observed according to each parameter. A repetitive load of 500 kPa and a static load of 1000 kPa were applied to the outside of the reinforcement area to evaluate the behavior of the subgrade when utilizing short reinforcement. The test results confirmed the reduction of the settlement and horizontal displacement of the wall, owing to the restraining effect of the short reinforcement and rigid wall. In addition, it was observed that the greater the applied load, the greater the influence of the reinforcement on the behavior of the subgrade; this pattern was more marked in loads above the yield of soil.

This paper focuses on development of the high energy saving timber building and ecological technology protecting environment in civil engineering. Wood framed with sheathing, large panel structures became more popular building constructions in Poland last decade. Experimental tests and numerical analysis of panels and complete wood framed building have been taken into account. Typical two-story residential building was selected for test. Test of three dimensional (3D) whole building was conducted on the base of experimental investigations results of large panel similar to those used in building structure. Also adequate tests of materials and connections were accompanying of the whole structure investigations. Obtained results were adopted in numerical models elaborated for wall and floor panels and in 3D model of whole building. Load -displacements characteristics were acquired from tests and numerical models. The displacements computed from 3D numerical model were 10–20% higher than from experiment. Experimentally ob-tained lower displacements than those from analytical analysis are resulted from higher stiffness of wall system due to diaphragms interconnections, their common interaction and three-dimensional character of building structure. Presented research analyzed method of computation of internal forces in building as well in the range of engineering methods in the form of rigid beam scheme up to the advanced methods using 3D spatial model adopting FEM.

In the present paper the design and construction choices of a test field for the ballast lateral resistance measurement, in order to produce data useful for the development of a numerical model able to simulate the service critical conditions of a continuous welded rail track, are described. Some construction details described herein allow to better understand the methodological approach followed in the design of experiments, the tests management philosophy as well as of the accuracy achieved in their implementation.

Several studies have been carried out until now by various Research Agencies and Railway Administrations to quantify the effects of the track-bed geometrical characteristics on the transverse strength of the track. Unfortunately, not all the possible scenarios in terms of track components, track-bed cross profile, operating conditions etc. have been investigated and not all the relevant variables have been directly measured. Therefore data available from the literature have different degrees of reliability. With the aim of enlarging the knowledge on the track stability and covering much of the possible relevant scenarios, an experimental research program has been developed in the framework of a cooperation between RFI, Italcertifer and DII. In order to perform the investigation under quite general conditions and to reduce the experimentation costs, n. 28 significant scenarios have been identified and reproduced on as many independent track segments. By applying on each track segment a transversal load, the strength of the ballast-sleeper interface has been determined. The results relative to the first four scenarios are presented in terms of applied load vs. lateral track displacement diagrams and in more synthetic numerical tables.