Purpose This study aims to further study the fire resistance of prefabricated concrete beam-column joints with end-plate connection. This paper aims to analyze the fire resistance of this joint in prefabricated reinforced concrete frame structure (PRCS). Design/methodology/approach First, the accuracy of the model is verified by using the test data. Based on this, a refined finite element model of PRCS structure with two stories and two spans is established. The influence of four working conditions with different fire floors (positions) and different axial compression ratios on the deformation, failure and fire resistance of PRCS structure are analyzed. Findings The results show that under the four working conditions, the fire resistance of the PRCS structure under Condition 1 and Condition 2 is smaller. It shows that the beam deformation develops slowly in PRCS structure under four kinds of fire positions, and the large displacement emerges 60 min later, which is poles apart from that of prefabricated beam column members. With the increase of the fire time, the material is damaged and deteriorated, which leads to the eccentricity of the axial load, so that the column top appears large lateral displacement. Under the Conditions 1 and 3, the lateral displacement of the column gradually decreases as the axial compression ratio rises. Originality/value It is found that there is a distinct lack of researching on the fire resistance of prefabricated joints, and the existed research studies are limited to the fire resistance of members. Thus, it is necessary to strengthen the first floor and side column design of prefabricated frame structure.

In this paper, the seismic performance of a prefabricated frame structure with a local outsource steel tube bolted column–column connect is evaluated from the perspective of seismic vulnerability theory. Firstly, a simplified model of the prefabricated frame structure was constructed and validated by experiments. Then, a six-story prefabricated reinforced concrete frame structure (PRCS) and a cast-in-situ reinforced concrete frame structure (CRCS) were designed as examples to get the increment dynamic analysis (IDA) of the structure under 12 ground motions, and the two-parameter damage model was used as the structural requirement index. As a traditional structural requirement index-the maximum inter-storey drift angle cannot accurately describe the mechanism of structural damage. Therefore, two types of damage models are compared and analyzed. In addition, in order to evaluate the damage of frame structure effectively, a new damage index weighted combination method is proposed, and its feasibility is verified. Finally, the IDA curve and vulnerability curve with Kunnath two-parameter damage model and the maximum inter-story displacement angle as the requirement index are drawn. The results show that the two-parameter damage model is more accurate than the maximum inter-storey drift angle model in evaluating the seismic performance of the PRCS and CRCS. It shows that the maximum inter-story displacement angle model can overestimate the collapse resistance of the PRCS by 60.7% on average, and the collapse resistance of the CRCS by 75.67% on average. The seismic performance of the CRCS is better than that of the PRCS as the seismic intensity increases. Although the seismic performance of fabricated columns is similar to that of cast-in-place columns, there is still a certain gap in the seismic performance of frame structures.

In order to study the dynamic response of the integrated station-bridge structure under the pile-soil interaction, a model was established by finite element software for dynamic analysis. According to a practical project, two mechanical models are established: one is the pile-soil interaction model, the other is the rigid foundation model. The dynamic responses of the two models were analyzed respectively, and then the results were compared. The results show that: the structure with pile-soil interaction has a longer period and higher flexibility; Under the action of frequently occurred earthquakes, the maximum displacement of the structure with pile-soil interaction increases and the base shear decreases; Under the action of seldomly occurred earthquakes, the structural displacement and base shear under the pile-soil interaction become larger, and the transverse displacement is more affected than the longitudinal displacement. It is concluded that: the assumption of rigid foundation makes the result more conservative, and the influence of pile-soil interaction cannot be ignored in seismic response analysis.

As the development of building industrialization and housing industrialization is speeding up in China, the application of precast concrete structure has been the research focus. The connection of prefabricated components is one of the key technologies in prefabricated concrete structure. So, a new type of column–column connection with steel plate hoop and bolts is proposed in this paper to promote the application of precast concrete structure. In order to reveal the flexural behavior and force transfer mechanism about this new type connection, six precast concrete beams and one integral casting beam were tested by the three-point bending under loading and unloading cycle. The comparative analysis is made between the new type connection and traditional integral cast-in-place member from the aspects of test phenomenon, failure mode, and load-deflection relationship. The analysis results show that the new type connection has the same bending bearing capacity as the integral casting member. Based on the analysis of the load-strain relationship of longitudinal reinforcement, bolts, and steel plate hoop, the moment transmission mechanism and theoretical calculation formula of the new type connection are proposed, and the theoretical calculation results are consistent with the experimental results.

Based on the current research status of screw-bored compaction cast-in-place piles (screw piles for short) and using ANSYS finite element software, in this research, a simulation analysis of the pile axial force and the side friction was conducted for three types of screw piles with different screw length ratios under vertical loading. The modeling analysis results were compared with the engineering data from a practical project in Anyang City, Henan Province, and the finite element model was validated. This research determined the effects of the screw length ratios on the pile axial force and the side friction and provided a theoretical foundation for the engineering design of a screw pile.