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Iran is one of the earthquake-prone countries in the world. The problem is that despite the studies and researches made, it seems that no significant progress has been achieved in the field of post-earthquake temporary shelter design, using climatic approach. The use of Conex and prevalent methods of providing temporary shelter for the homeless after the recent disasters in Iran has not been effective due to the lack of adaptation to the climate, context, and characteristics of the affected area. On the one hand, they have caused long-term problems in the area, and on the other hand, they have wasted financial resources. Therefore, the purpose of this article is to design alternatives for post-earthquake temporary shelter in the city of Isfahan, Iran, located in hot-arid climate. In this regard, to find the best result, alternatives are designed and the final alternative is presented, by recognizing and analyzing the indicators and criteria of the temporary shelter, as well as framework development based on the context and conditions of the climate. The findings of this study display that in addition to criteria of 'upgradable', 'reusable', 'relocatable', 'recyclable', and 'resaleable', it is recommended to consider other criteria including 'climatic', 'modular', 'community-based', 'multi-functional', and 'context-based' in the design of post-earthquake temporary shelter. The practical implication of the article is that the developed criteria are generalizable, and the alternatives proposed can be used in similar climates and answer the challenges related to thermal comfort, transportation, recycling, assembling, upgradability, flexibility, and modularity of temporary shelter units. [ABSTRACT FROM AUTHOR]

Copyright of Modern Urban Transit is the property of Modern Urban Transit 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 Railway Construction Technology is the property of Railway Construction Technology 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.)

The slope protection structure of the prefabricated lattice beam is one of the most widely used and studied systems in slope structure, with the connection between the lattice beam joint and the longitudinal and transverse beams being critical for structural performance and stability in engineering applications. Because the prefabricated structure is weak in its structural integrity, it is necessary to study the influence of prefabricated lattice beam joints and the longitudinal and transverse beams on the overall mechanical properties of the structure. In this paper, one ordinary cast-in-place concrete beam and six prefabricated beams with different joint-connection modes are designed, and the influence of different connection modes on the bending capacity of the beams is accordingly explored. Moreover, the flexural capacity, bending stiffness change, ductility, and energy absorption capacity of the beams are analyzed through three-point bending test. The test results show that the connection mode at the joints could significantly affect the overall mechanical properties of the structure. By embedding holes in steel sleeves, filling cement mortar in the middle, and using steel plates with a thickness of 16 mm for anchoring treatment joints of end plates, the specimen beams are thus obtained with the same flexural capacity, ductility, and energy absorption capacity as ordinary cast-in-place concrete beams. This study provides valuable insights into optimizing connection methods for prefabricated beams, which can lead to improved structural performance and wider adoption of prefabricated structures in the construction industry. [ABSTRACT FROM AUTHOR]

This study conducts quasi-static tests and finite element (FE) analysis by using ABAQUS software to examine the effects of floor combination effect (FCE) on the seismic behavior of a novel type of prefabricated steel-concrete composite (PSCC) exterior joints. This analysis assesses PSCC exterior joints featuring bolted-welded hybrid connections, focusing on their seismic performance under the influence of FCE. The variables in this research include floor construction parameters, axial compression ratio (n), and core area concrete (CAC). The results indicated that these variables, particularly the floor construction parameters, n, and CAC, significantly influence stress distribution and magnitude within the joint core area (JCA) and the floor slab. Although the floor construction parameters exert a minor effect on seismic performance, increasing n markedly enhances the joints' load-bearing and energy dissipation capacities. However, it also makes the joints more susceptible to brittle failure. Optimal bearing capacity and ductility for energy dissipation are achieved when n equals 0.3. In addition, CAC substantially increases the initial stiffness (IS) and bearing capacity, with a peak increase in bearing capacity of approximately 18% and an IS enhancement of around 25%. However, rising CAC strength has a relatively minor impact on seismic performance. [ABSTRACT FROM AUTHOR]

An extensive experimental program was performed to evaluate the structural behavior of a novel fully prefabricated noise barrier wall system. The experimental investigation entailed the fabrication and testing of two full-scale prototypes, which was the foundation for implementing a systematic parametric nonlinear finite-element analysis (NLFEA) study. The intent was to assess the impact of four critical parameters on the overall structural behavior of the noise barrier wall system for further optimization and improvement. These critical parameters include the integral column size, the presence of a gap, the type of steel section utilized, and the embedment length of the steel section. Therefore, the parent nonlinear finite-element analysis model was created, calibrated, and verified against the experimental results of the full-scale prototypes in terms of the load–deflection curves, load–strain curves, cracking patterns, and failure modes. Then, various nonlinear finite-element analysis models were created by expanding the parent model to allow for evaluating various possibilities from each parameter. For a preidentified performance acceptance criterion, the findings of the study revealed that the integral column size could be reduced from the size used in the prototypes, the embedment length of the steel section was already at an optimum length, the existence of a gap would result in the prevention of any sliding, and a circular hollow steel section (HSS) 14×15.875 mm (5/8 in.) or W8×48 would represent the most advantageous selection for the steel column section. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology 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 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.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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.)

This study investigates the impact of using prefabricated facade materials on the embodied energy (EE) and operational energy (OE) consumption of apartment buildings. To analyze the total EE, a life cycle assessment (LCA) was conducted, which calculated the EE from cradle-to-use each of the products employed. In addition, a building energy simulation was performed for the case study building using various prefabricated facade materials to assess its OE. The findings reveal that the selection of facade wall materials with low energy intensity must be favored to optimize building energy and that layered materials, such as insulated panels, can reduce the cooling energy load due to their higher thermal resistance (r- values). Furthermore, the LCA results showed that solid precast concrete materials with thicknesses of 120 and 150 mm have EE and greenhouse gas emissions that are more than twice the average of all materials tested. In contrast, uninsulated Glass-Fiber Reinforced Concrete (GRC) removable walls (disassembly panels) exhibited the lowest EE, corresponding to 50% of the average. Finally, the results of the OE simulations using EnergyPlus software indicate that insulated GRC removable walls with a thickness of 120 mm can reduce the cooling energy load by 29.5% compared to precast concrete facades.

Prefabrication is an innovative construction method for mass-produced and low-cost buildings in response to an urgent demand for educational facilities in challenging times, such as natural disasters or wars. This study assesses the spatial quality of prefabricated schools constructed in Duhok, the north of Iraq, and considers the needs of refugee children relocating from damaged areas. The study compares the spatial quality (spatial transparency, spatial connectivity, and spatial flexibility) of 10 prefabricated schools to traditional design and construction. The methodology used is collecting indicators related to the spatial quality of the school as standards, followed by selecting available indicators in the case study and analyzing cases using space syntax theory and DepthmapX (version 0.8.0) software. The results showed that prefabricated schools have higher spatial integration, connectivity, and flexibility than the traditional way of construction. The study concluded that the spatial pattern of spaces that are used in prefabricated schools applies more to the requirements of modern school spatial quality than the traditional way of spatial patterning. [ABSTRACT FROM AUTHOR]

Objective At present, the structural system of prefabricated underground stations in China presents diversified development characteristics, but lacks systematic classification. Therefore, the research progress on the structural performance of open-cut prefabricated underground stations is sorted out. Method Aiming at the current mainstream structure forms, the structural system characteristics of open-cut prefabricated underground stations are systematically summarized. The research on the structural performance of the above stations is organized from prefabricated elements, joint connections and overall structure three levels. The development direction of open-cut prefabricated underground stations is proposed. Result & Conclusion The structure of open-cut prefabricated underground stations can be classified into two categories: prefabricated-monolithic type and fully-assembled type. The research on prefabricated components of assembled underground station mainly focuses on the bearing performance of assembled plate components. The joint connection of prefabricated components is related to the bearing and seismic performance of the overall structure for the prefabricated underground station, and therefore is the focus of the research. The bearing and seismic performance of prefabricated underground structures is mainly investigated by numerical methods, and lacks experimental data on the overall structure. Studies on the load bearing performance of the above station considering the whole life cycle will become an important research direction.

Summary: More and more prefabricated steel–concrete hybrid wind turbine towers have been built because of their better lateral stiffness than those of the full steel towers, in which epoxy resin joints are commonly adopted at the horizontal joint between two ring units for improving the erection speed. In fact, epoxy resin joints are designed in the same way as dry joints due to the very thin thickness of epoxy resin layer, in which epoxy resin only acts as a leveling blanket and sealer for jointing and compensates for the unevenness of the contact surface between two ring units. The current design method for the resistance to torsional moment at the horizontal joint is not reasonable because of the unreasonable assumption of Saint‐Venant's torsional theory. The integral expressions of the ultimate torsional moment at the horizontal joint with and without shear force are derived, respectively. The solution of the integral expressions for the ultimate torsional moment is realized by Python programming. The refined finite element analyses of two cases are compared with the existing small‐scale tests with segmental aluminum tubes, which verifies the calculation accuracy of the proposed integral method. In the modified integral model of the ultimate torsional moment, a correction term of the resistance to torsional moment and a more suitable distribution of shear stress under the action of horizontal shear force are proposed to obtain a more accurate ultimate torsional moment. Finally, 36 sets of cases with typical dimensions and axial forces in practical engineering are analyzed by the proposed integral model in the absence of horizontal shear force. One six‐parameter model for calculating the ultimate torsional moment is fitted by the least square method. A discount factor is proposed to consider the influence of the horizontal shear force on the ultimate torsional moment. [ABSTRACT FROM AUTHOR]

Because they have foundations with two or more different elevations, the mechanical performance of structures in mountain cities is significantly different from that of common structures. Our simulation method and the parameters of a typical bolt steel plate-based dry connection joint were verified based on the static load test of a fully assembled substructure against progressive collapse. The load–displacement curves and the displacement–time history curves of the failure point of six kinds of column removal conditions were obtained by using static nonlinear and dynamic nonlinear analysis methods, establishing a different number of dropped stories and spans for the prefabricated step-terrace frame structure models. Based on the ultimate load amplification factor and the maximum dynamic displacement at the failure point, the progressive collapse performance of prefabricated frame structures in mountain cities, including the number of dropped stories and spans, was obtained. The results show that the progressive collapse performance of a prefabricated step-terrace frame structure is inferior to that of a common prefabricated frame structure. The progressive collapse performance is stronger when the upper ground columns fail than that when the dropped ground columns fail. The progressive collapse performance of the prefabricated step-terrace frame structure decreases gradually with the increase in the number of dropped stories and increases gradually with the increase in the number of dropped spans. With the increase in the number of dropped stories, the redundancy of the structure is reduced, and the progressive collapse performance of the dropped stories is reduced by more than that of the upper stories. The increase in the number of dropped spans increases the redundancy of the structure, and the improvement in the progressive collapse performance of the dropped stories is greater than that of the upper stories. This paper provides a reference for the progressive-collapse-resistant design of step-terrace frame structures in mountain cities. [ABSTRACT FROM AUTHOR]

In order to meet the bearing requirements of prefabricated composite slab‑column joints, two types of connection joints between steel‑concrete‑steel sandwich slab and structural column are proposed. Using ABAQUS finite element software, the numerical calculation model of composite slab column joint is established, and the bearing capacity of precast joint under punching load and the influence of main design parameters on its mechanical and deformation properties are analyzed. The results show that, compared with the cast‑in‑place joints under the same condition, the prefabricated connection joints can significantly increase the punching shear capacity while ensuring good ductility. These indicate that the connection components can make a positive contribution to the punching shear resistance of the joints. In addition, it is recommended to use a 16 through bolts radial arrangement and choose a square or cross shaped external diaphragm in the external diaphragm‑thru bolt connection. The diaphragm’s strength grade is consistent with the composite slab, which is taken as Q345. For the cantilever composite slab‑circumferential flange connection, it is suggested that the flange thickness should be controlled at about 20 mm, so as to make the joint own a higher cost performance. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology 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.)

Objective: The demand for esthetics has increased in today's world and most parents prefer to preserve their children's primary anterior teeth until their natural exfoliation. However, an intracanal post is required to provide retention for reconstruction of severely damaged anterior teeth due to caries or trauma. Various materials and methods may be used for the fabrication of intracanal posts. This study assessed the fracture strength and fracture mode of primary canine teeth reconstructed with prefabricated and customized polyethylene and glass fiber posts. Materials and Methods: This in vitro study evaluated 60 extracted primary canine teeth in four groups (n = 15). After pulpectomy and post space preparation with 4 mm depth, composite resin post, prefabricated glass fiber post (Whitepost), customized glass fiber post (Interlig), or customized polyethylene fiber post (Ribbond) were placed in the root canals to provide retention, and the tooth crown was restored with bulk‐fill composite resin. The fracture strength was then measured in a universal testing machine. The fracture mode was also evaluated visually. Results: The mean fracture strength was 22.45 ± 5.06, 33.10 ± 8.5, 30.20 ± 7.33, and 32.61 ± 5.73 N/mm2 in the composite resin post, Whitepost, Interlig, and Ribbond groups, respectively. The fracture strength was significantly lower in the composite group than in the remaining three groups (p = 0.000). No other significant differences were found (p > 0.05). Also, no significant difference was observed among the study groups in the fracture mode (p = 0.241). Conclusion: The composite resin post yielded a significantly lower fracture strength than the prefabricated and customized glass and polyethylene fiber posts, but the fracture mode was not significantly different among the four groups. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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 Urban Mass Transit is the property of Urban Mass Transit 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 investigates the structural performance of a new prefabricated H-shaped steel beam assembled using high-strength bolts under three-point bending. The study evaluates four bolt hole types in five layout schemes through experimental tests. The results show that specimens with standard round holes in both the H-shaped steel and connecting plates exhibited 11% to 30% higher flexural bearing capacity compared to other hole types. Additionally, ANSYS simulations closely matched the experimental results, with a 6% difference. The research results provide important references for the design of prefabricated H-shaped steel beams with different bolt hole types, offering a practical foundation for enhancing the flexural performance of steel beam designs. [ABSTRACT FROM AUTHOR]

This study analyzes the nonlinear seismic behavior of cluster-connected prefabricated shear walls under varying axial compression ratios. The investigation focuses on the connectivity of shear wall segments assembled using cluster connections rather than separate walls connected by beams. Using the finite element software ABAQUS, this study simulates monotonic horizontal displacement loading to evaluate the yield strength, peak strength, and deformation capacity of the shear walls. The results demonstrate that the horizontal load-bearing capacity of the shear wall significantly improves with an increase in axial compression ratio, while the axial compression ratio also influences ductility. The numerical simulations are validated against experimental data, confirming the accuracy of the model. These findings provide essential insights for optimizing the seismic design of precast shear walls. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. 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.)

The study focuses on developing a prefabricated panel for non-structural purposes by optimizing mortar mix designs incorporating recycled microplastic (RMP) and construction demolition waste (CDW) at various ratios (0, 10, 20, 30, and 100%). Experimental procedures encompassed material characterization, mortar specimen manufacturing, compression resistance testing, and thermal/acoustic panel tests following Colombian technical standards. Results indicate that incorporating 20% CDW enhances material strength, with cylinder number 3 (20% of CDW) achieving a resistance of 31.45 MPa. Panels incorporating recyclable waste materials show improved acoustic and thermal insulation properties, with up to 39 dB reduction in sound transmission and a 21 °C decrease in thermal transmission observed (5.6% and 35% for panel and door, respectively). This research advances sustainable construction practices demonstrating the potential of prefabricated panels using recyclable materials, offering eco-friendly solutions with enhanced performance characteristics for construction applications. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology 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 Railway Construction Technology is the property of Railway Construction Technology 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.)

To investigate the seismic performance of a fully assembled framework consisting of prefabricated autoclaved lightweight concrete (ALC) wall panels with partially encased concrete T-shaped columns, a horizontal low-cycle reciprocating load test was conducted on a non-open hole ALC wall panel specimen and an ALC wall panel specimen with a rectangular opening. The influence of the opening on the structure was analyzed, and a comparative discussion is carried out in this article on hysteresis curves and skeleton curves. The experimental results showed that a wall panel opening weakened the overall integrity of the wall, resulting in stress concentration around the door opening and accelerated the damage to the infill wall. In addition, a numerical model was established for analysis, and the finite element results were cross-verified with the experimental results. Based on the experimentally validated numerical model, the influence of different opening parameters on the lateral resistance performance of the framework combination was analyzed, providing theoretical references for engineering construction. [ABSTRACT FROM AUTHOR]

Using bolts as shear connectors of the steel–concrete composite beams enables prefabricated assembly and makes it possible to demountable and reuse the prefabricated components. However, studies on the fire resistance of prefabricated demountable composite beams (PDCBs) connected by bolts are limited. In this paper, four full-scale fire resistance tests were conducted to investigate the fire resistance of PDCBs connected by shear bolts with profiled sheet ribs parallel to the steel beam. Experimental observations, heating curves, deformation curves, and critical temperatures of specimens were obtained through fire-resistant tests. Test results show that the shear failure of bolted connectors occurred in the partially connected PDCBs instead of in the fully connected ones. Under the same load ratio, the fire resistance limit of PDCBs with fire protection was 4.4 times that of PDCBs without fire protection. The temperatures of the upper flanges of the steel beams in the PDCBs were overestimated by the existing codes. Moreover, numerical heat transfer analysis was carried out to investigate the effect of concrete slab thickness, concrete moisture content and steel beam upper flange dimensions on the temperature distribution of the steel beam upper flange. Finally, based on the results, relevant recommendations are made for the method of calculating the temperature of the steel beam upper flange in the PDCBs. [ABSTRACT FROM AUTHOR]

Aiming at the complex steel bar layout problem in prefabricated building, this research proposes a structural design method of prefabricated building based on big data simulation modeling building information modeling technology. It includes the reinforcement arrangement model based on agent path planning, the intelligent reinforcement arrangement of frame based on artificial potential field method and path optimization, and the modeling of Building information modeling. When analyzing the reinforcement arrangement effect of beam column joints in Prefabricated building, the calculation time of top corner joints is the shortest, 76.8 seconds, while that of middle layer joints is the longest, 141.7 seconds. In direction Y and direction X, differential evolution has the longest calculation time, 27s and 26.57s respectively, while particle swarm optimization algorithm has the shortest calculation time, 2.84s and 3.02s respectively. The algorithm designed through research is significantly superior to other algorithms in terms of computational time. In general, through building information modeling technology and big data simulation modeling, this study realized the collision free layout of rebar in beam column joints of prefabricated building. This improves the speed and efficiency of deepening design, and provides a new solution for structural design of prefabricated building. [ABSTRACT FROM AUTHOR]

The mountain area is faced with complex coJdjtions sucn as vertical and horizontal valleys, complex geologd topography, Vmny earthquake fault zones, high seismic intensityfriBk ecologyBkcriangeable climate. The traditional concrete bridgee heavy weilrhigh consumption of sand and gravel materials, large structural dimensions of steel box composite bridges, high steel consumption, and poor overall horizontal performance of steel plate composite beams, which are not suitable for mountain construction conditions. Thejefore, based onthe construction environment and application requirements of highway bridges in mountainous areas, the structural scheme of steeHX-steel pete composite beam is put forward in this paper, and the design 50 m landaTa-span steel box-steel plate composite beam is studied. Jrfl®iesu[ts show that the steel box-steel plate composite beam structure scheme is adopted, which has excellent mechanical characteristics of steel box girder and k simple structure of steel plate girder. It has the mechanical characteristics of balancidtransverse force and excellent longitudinal force", so it is a reasonable choice for small radius curved beam bridge in a mountainous area, so it is a reasonable choice for small radius curved beam bridge in a mountainous area. The steel box-steel plate composite beam adopts the integrated technology of manufacture, transportation and installation, which can better meet the road transport conditions in the mountain area. The longitudinal assembly of the manufacturing unit as the installation unit can ensure the rapid and high-precision installation of the construction site, and the assembly construction of the bridge in the mountain area has been realized. The technical and economic comparison shows that the mechanical performance of steel box-steel plate composite beam is similar to that of steel box beam and obviously better than that of steel plate girder. The steel consumption and construction period of steel box- steel plate composite beam are similar to that of steel plate girder, and are significantly less than that of the steel box girder. Therefore, the steel box- steel plate composite beam is a good choice for mountain bridge construction. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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.)

The "321" prefabricated highway steel truss bridge is widely used for highway rescue, disaster relief, and emergency traffic. This paper uses a 33 m double-row monolayer "321" prefabricated highway steel truss bridge to analyze its mechanical properties and component stability. The actual traffic flow capacity of a total weight of 53.32 tons is used in this study. The results show that the maximum internal force in the truss chord (including the stiffening chord) occurs in the middle span section when a centrally distributed load is applied. Meanwhile, the maximum internal force of truss diagonal members and truss vertical bars appears at the fulcrum section. Under the eccentrically distributed load, the maximum internal forces of truss chords (including stiffening chords) appear in the middle span section, which is closest to the vehicle load, while the maximum internal forces of truss diagonal members and truss vertical bars appear in the fulcrum section, which is closest to the vehicle load. While the maximum internal forces under the eccentrically distributed load are greater than the maximum internal forces under the centered-layout load, under the vehicle load, truss chords (including stiffening chords) are prone to buckling instability, and the buckling mode is mainly reverse out-of-plane buckling. The inclined members of the truss are prone to buckling instability, and the buckling mode is mainly the combination of out-of-plane bending and two-way out-of-plane bending. Truss vertical bars have good stability and are not easy to buckle. The main conclusions of this paper can provide references for the optimal design and operation safety of prefabricated highway steel truss bridges. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ege University School of Dentistry / Ege Üniversitesi Dis Hekimligi Fakültesi Dergisi is the property of Ege University Faculty of Dentistry 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.)

Abstract Objective The demand for esthetics has increased in today's world and most parents prefer to preserve their children's primary anterior teeth until their natural exfoliation. However, an intracanal post is required to provide retention for reconstruction of severely damaged anterior teeth due to caries or trauma. Various materials and methods may be used for the fabrication of intracanal posts. This study assessed the fracture strength and fracture mode of primary canine teeth reconstructed with prefabricated and customized polyethylene and glass fiber posts. Materials and Methods This in vitro study evaluated 60 extracted primary canine teeth in four groups (n = 15). After pulpectomy and post space preparation with 4 mm depth, composite resin post, prefabricated glass fiber post (Whitepost), customized glass fiber post (Interlig), or customized polyethylene fiber post (Ribbond) were placed in the root canals to provide retention, and the tooth crown was restored with bulk‐fill composite resin. The fracture strength was then measured in a universal testing machine. The fracture mode was also evaluated visually. Results The mean fracture strength was 22.45 ± 5.06, 33.10 ± 8.5, 30.20 ± 7.33, and 32.61 ± 5.73 N/mm2 in the composite resin post, Whitepost, Interlig, and Ribbond groups, respectively. The fracture strength was significantly lower in the composite group than in the remaining three groups (p = 0.000). No other significant differences were found (p > 0.05). Also, no significant difference was observed among the study groups in the fracture mode (p = 0.241). Conclusion The composite resin post yielded a significantly lower fracture strength than the prefabricated and customized glass and polyethylene fiber posts, but the fracture mode was not significantly different among the four groups.

The slope protection structure of the prefabricated lattice beam is one of the most widely used and studied systems in slope structure, with the connection between the lattice beam joint and the longitudinal and transverse beams being critical for structural performance and stability in engineering applications. Because the prefabricated structure is weak in its structural integrity, it is necessary to study the influence of prefabricated lattice beam joints and the longitudinal and transverse beams on the overall mechanical properties of the structure. In this paper, one ordinary cast-in-place concrete beam and six prefabricated beams with different joint-connection modes are designed, and the influence of different connection modes on the bending capacity of the beams is accordingly explored. Moreover, the flexural capacity, bending stiffness change, ductility, and energy absorption capacity of the beams are analyzed through three-point bending test. The test results show that the connection mode at the joints could significantly affect the overall mechanical properties of the structure. By embedding holes in steel sleeves, filling cement mortar in the middle, and using steel plates with a thickness of 16 mm for anchoring treatment joints of end plates, the specimen beams are thus obtained with the same flexural capacity, ductility, and energy absorption capacity as ordinary cast-in-place concrete beams. This study provides valuable insights into optimizing connection methods for prefabricated beams, which can lead to improved structural performance and wider adoption of prefabricated structures in the construction industry.

During the construction of the shore connecting section of the immersed tunnel, a secondary water stop structure is installed in the thrust section to ensure waterless construction conditions. For the convenience of construction, a modular and detachable steel buttressed cofferdam structure is designed to achieve rapid installation and disassembly of secondary water stop structures. In this paper, the stress and deformation are analyzed by finite element software and compared with deformation data monitored during actual construction process. The research results indicate that the prefabricated steel buttress structure has good water stopping effect, convenient construction, saving construction costs and construction period, and provides new ideas for the design of water stop structures. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. 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 Railway Investigation & Surveying is the property of Railway Investigation & Surveying 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 China Forest Products Industry is the property of China Forest Products Industry 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.)

To explore the development value of different freshwater fish productions of prefabricated grilled fish and realize the diversified development of prefabricated grilled fish categories, an analysis was hereby carried out on the nutritional and textural characteristics of prefabricated grilled fish processed from six common freshwater fish. The results showed that there was no significant difference in the moisture and ash content (P>0.05), the protein content ranged from 21.87%~24.28%, and the fat content was low in all six types of grilled fish. Besides, the content of glutamic acid, aspartic acid and lysine was high, and that of the total essential amino acids ranged from 7.71~9.42 g/100 g. Among them, that of common carp and Wuchang fish was higher, followed by tilapia and grass carp, Wuchang fish, common carp and tilapia had a high fresh amino acid content. The ratio of the essential amino acids to the total amino acids of the six grilled fish was about 40%, which was a high-quality animal protein source. According to the amino acid score, the first limiting amino acid of all six grilled fish was methionine+cysteine, common carp had the highest essential amino acid index, followed by tilapia. Besides, a total of 22 fatty acids were detected in the six grilled fish species, which had a high proportion of unsaturated fatty acids. Tilapia and Wuchang fish contained high functional fatty acids with a high nutritional value, such as eicosapentaenoic acid and docosahexaenoic acid. Through the principal component analysis, the comprehensive score of nutritional indicators followed the order of tilapia>Wuchang fish>common carp>grass carp>crucian carp>pincer fish, while in terms of textural characteristics, the elasticity and chewiness of tilapia and Wuchang fish were significantly（P

Because they have foundations with two or more different elevations, the mechanical performance of structures in mountain cities is significantly different from that of common structures. Our simulation method and the parameters of a typical bolt steel plate-based dry connection joint were verified based on the static load test of a fully assembled substructure against progressive collapse. The load–displacement curves and the displacement–time history curves of the failure point of six kinds of column removal conditions were obtained by using static nonlinear and dynamic nonlinear analysis methods, establishing a different number of dropped stories and spans for the prefabricated step-terrace frame structure models. Based on the ultimate load amplification factor and the maximum dynamic displacement at the failure point, the progressive collapse performance of prefabricated frame structures in mountain cities, including the number of dropped stories and spans, was obtained. The results show that the progressive collapse performance of a prefabricated step-terrace frame structure is inferior to that of a common prefabricated frame structure. The progressive collapse performance is stronger when the upper ground columns fail than that when the dropped ground columns fail. The progressive collapse performance of the prefabricated step-terrace frame structure decreases gradually with the increase in the number of dropped stories and increases gradually with the increase in the number of dropped spans. With the increase in the number of dropped stories, the redundancy of the structure is reduced, and the progressive collapse performance of the dropped stories is reduced by more than that of the upper stories. The increase in the number of dropped spans increases the redundancy of the structure, and the improvement in the progressive collapse performance of the dropped stories is greater than that of the upper stories. This paper provides a reference for the progressive-collapse-resistant design of step-terrace frame structures in mountain cities.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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.)