Frequency: Quarterly E- ISSN: New Release P- ISSN: New Release
â??Inventi Rapid/Impact: Civil Structuresâ?? is a peer reviewed journal of Engineering & Technology. The journal provides publishing space for the research and review papers and reports related to all the areas of civil structures including structural and infrastructural engineering, geomatics, geosciences and geographical information systems, emerging areas of civil engineering, advances in concrete research, and new building materials etc. \n\nThe journal is open to negative reports and provides special consideration to the articles pertaining to structural research aimed at solving the issues of underdeveloped or provincial communities. \n
.e phenomenon of hospital functional interruption has been widely observed in the historical moderate-strong earthquakes,\nindicating that hospital functionality cannot be well considered in the current seismic design methods. .e concept of seismic\nresilience pays enough attention to postearthquake functionality of buildings, and it is particularly significant for the urban\nhospitals which play critical role in the urban postearthquake rescue and recovery. .is study proposes a framework to assess the\nseismic resilience of urban hospitals, by incorporating the fault tree analysis (FTA) to consider the interdependency between the\ndamage of nonstructural components and the functionality of medical equipment, as well as the effect of external supplies on the\nfunctionality of hospital. .e proposed framework is then applied to a case-study hospital, and the results indicate that this\nhospital needs 1.1 days to resume emergency functionality under REDi repair strategy after design basis earthquake (DBE), while it\nneeds 28.8 days to resume emergency functionality under REDi repair strategy after maximum considered earthquake (MCE). It is\nfound that the seismic resilience of this hospital after MCE cannot meet the community requirements on the recovery time, and\nnecessary measures are needed to improve the seismic resilience. .e proposed framework provides the quantitative results of\nseismic resilience assessment in the preearthquake environment and can further support emergency response planning and\nseismic retrofits strategies....
Based on the triaxial test, the elasto-perfectly plastic strain-softening damage model (EPSDM) is proposed as a new four-stage\nconstitutive model. Compared with traditional models, such as the elasto-brittle-plastic model (EBM), elasto-strain-softening model\n(ESM), elasto-perfectly plastic model (EPM), and elasto-peak plastic-brittle plastic model (EPBM), this model incorporates both the\nplastic bearing capacity and strain-softening characteristics of rock mass. Moreover, a new closed-form solution of the circular tunnel\nis presented for the stress and displacement distribution, and a plastic shear strain increment is introduced to define the critical\ncondition where the strain-softening zone begins to occur. The new analysis solution obtained in this paper is a series of results rather\nthan one specific solution; hence, it is suitable for a wide range of rock masses and engineering structures. The numerical simulation\nhas been used to verify the correctness of the EPSDM. The parametric studies are also conducted to investigate the effects of\nsupporting resistance, residual cohesion, dilation angle, strain-softening coefficient, plastic shear strain increment, and yield parameter\non the result. It is shown that when the supporting resistance is fully released, both the post-peak failure radii and surface\ndisplacement could be summarized as EBM>EPBM >ESM>EPSDM> EPM; the dilation angle in the damage zone had the highest\ninfluence on the surface displacement, whereas the dilation angle in the perfectly plastic zone had the lowest influence; the strainsoftening\ncoefficient had the most significant effect on the damage zone radii; the EPSDM is recommended as the optimum model for\nsupport design and stability evaluation of the circular tunnel excavated in the perfectly plastic strain-softening rock mass....
Inflow and infiltration (I&I) is an unavoidable problem which affects underground infrastructures such as water mains, sewer\nlines, and storm water systems. The additional water and intruded debris, due to I&I, can hinder the flow capacity of the pipe\nnetwork. However, with proper management, such problems can be minimized or controlled. By using a qualitative approach to\ndetermine the areas susceptible to I&I, application of geographic information system (GIS) can minimize cost and time. The\nresults found can highlight the most I&I vulnerable areas, which can be used for underground infrastructure management. In this\nstudy, maps of Youngstownâ??s sewer lines and surrounding areas were generated and used. Pipe age, an empirical operating\ncoefficient, sewer classifications, and soil hydraulics were the parameters used to identify each pipe segments. The results of this\nstudy show that majority of pipelines from downtown and south side of the city were determined to be in very poor conditions.\nThe method used in this study reduces the scale of work, by generating a map, indicating areas with highest susceptibility....
A study concerning the performance assessment and enhanced retrofit of public buildings\noriginally designed without any anti-seismic provisions is presented herein. Arepresentative structure\nbelonging to this class was demonstratively examined, i.e., a school built in Italy in the early 1970s,\nbefore a coordinate national Seismic Standard was issued. The building is characterized by a mixed\nreinforced concrete (ground storey)-steel (first and second storey) frame skeleton. An extensive\non-site experimental investigation was developed in the first step of the study, which helped identify\nthe mechanical characteristics of the constituting materials, and re-draw the main structural details.\nBased on these data, and relevant updates of the finite element model of the structure, the seismic\nassessment analyses carried out in current conditions highlighted several performance deficiencies,\nin both the reinforced concrete and steel members. An advanced seismic retrofit hypothesis of the\nbuilding was then designed, consisting of the installation of a set of dissipative braces incorporating\nfluid viscous dampers as protective devices. This solution makes it possible to attain an elastic\nstructural response up to the maximum considered normative earthquake level, while at the same\ntime causing more limited architectural intrusion and lower costs as compared to conventional\nrehabilitation strategies....
Stress interference of multiplied fractures has significant influences on the propagation\nbehavior of hydraulic fractures in roads, bridges, clay formations, and other forms of engineering. This\npaper establishes a crossing criterion and initiation angle model with comprehensive consideration of\nremote stress, stress intensity near the tip of fracture, and stress interference of multiplied fractures.\nCompared with the existing crossing criterion and initiation angle model, the ability to cross natural\nfractures decreases. Furthermore, the secondary initiation angle decreases with consideration of\nmultiplied fracture propagation. The length of hydraulic fractures and natural fractures has little\ninfluence on the secondary initiation angle. With the increase in fracture space, the stress interference\nbetween fractures decreases, and as a result, the initiation angle begins to increase and then decrease.\nDiffering from the propagation behavior of single fracture, the initiation angle basically does not vary\nwith the increasing of net pressure under the high intersection angle between hydraulic fractures and\nnatural fractures. Under a low intersection angle condition, the bigger the net pressure is, the smaller\nthe initiation angle is. These results have great significance when analyzing the propagation behavior\nof multiplied fractures in real-world applications....
The analysis of the ductility and cumulative plastic deformation (CPD) demand of a high-performance buckling-restrained brace\n(HPBRB) under a strong earthquake and its aftershocks is conducted in this paper. A combination of three continuous excitations\nwith the same ground motion is used to simulate the affection of a strong earthquake and its aftershocks. A six-story HPBRB frame\n(HPBRBF) is taken as an example to conduct the incremental dynamic analysis (IDA). The seismic responses of the HPBRBF\nunder one, two, and three constant continuous ground motions are compared. TheIDA result indicates that the ductility and CPD\ndemand of the BRBs under the three constant continuous ground motions are significantly larger than that excited by only one.\nProbabilistic seismic demand analysis (PSDA) is performed using seven near-fault ground motions and seven far-fault ground\nmotions to consider the indeterminacy of ground motion. The probabilistic seismic demand curves (PSDCs) for the ductility and\nCPD demand for the HPBRB under the strong earthquake and its aftershocks are obtained in combining the probabilistic seismic\nhazard analysis. The results indicate that the AISC threshold value of the CPD with 200 is excessively low for a HPBRBF which\nsuffers the continuous strong aftershocks with near-fault excitations, and a stricter threshold value should be suggested to ensure\nthe ductility and plastic deformation capacity demand of the HPBRB....
The transition from experimental studies to the realm of numerical simulations is often\nnecessary for further studies, but very difficult at the same time. This is especially the case for\nextended seismic analysis and earthquake-resistant design. This paper describes an approach to\nmoving from the experimental testing of an elementary part of a wood-frame building structure to\na numerical model, with the use of a commercial engineering analysis software. In the presented\napproach, a timber-frame structure with polyurethane (PU)-foam insulation and OSB (oriented\nstrand board) sheathing was exposed to dynamic excitation. The results were then used to generate\na numerical 3D model of the wooden frame element. The process of creating the 3D model is\nexplained with the necessary steps to reach validation. The details of the model, material properties,\nboundary conditions, and used elements are presented. Furthermore, the authors explain the technical\npossibilities for simplifying the numerical model in used software. Simplifying the model leads to a\nsubstantial reduction of calculation time without the loss of accuracy of results. Such a simplification\nis especially useful when conducting advanced numerical calculations in the field of seismic and\ndynamic resistant object design....
In the shaking table test of large cassette structure, story drift is an essential set of experimental data.-etraditional method of displacement\nmeasurement is limited to problems such as necessary full contact with the structure model for installation of sensors, large work of\ninstallation, and easily interfered by environment. -e noncontact displacement measurement method, such as optical measuring\ntechnology, can solve the above problems and serve as an effective supplementary method for traditional displacement measuring in the\nshaking table test. -is paper proposed a vison-based displacement measuring method. Predesigned artificial targets which act as sensors are\ninstalled on each floor of the cassette structure model. A high-speed industrial camera is used to acquire the series of the images of the\nartificial targets on the structure model during the shaking table test. A Python-OpenCV-based structural calculation program combining\ncomputer vision and machine vision is developed to extract and calculate the displacement of the artificial targets from the series of the\nimages acquired....
The reasonable assessment of potential damage type of masonry structures in seismic-prone zone is very significant to strengthen\nexisting masonry structures and guide the construction of the new building. The primary objective of the study is to propose and\ndetermine a reasonable assessment index to predict the damage type of masonry structures in different seismic intensity zones using\nthe survey results of the 2008Wenchuan earthquake and variance analyses comparison methods.Three potential theory assessment\nindexes are considered in the evaluation of damage of masonry structures, including wall density index ...
Curved surface sliders are being used more and more in the seismic isolation of buildings. *ey are preferred not only because of\ntheir lower cost with respect to elastomeric isolators but also of their technical characteristics, such as the fact that the value of the\nperiod of vibration is independent of the mass and the automatic coincidence between the gravity mass center of the superstructure\nand the stiffness center of the isolation system. In this paper, these features are analysed with reference to simple\nstructures, pointing out the possibility of rotations of the superstructure and the loss of contact in some devices. Finally, the\nimportance of the static friction is also emphasized showing the experimental seismic response of an isolation system under a lowenergy\nearthquake. For all these reasons, the use of nonlinear analysis, revised and detailed in this paper, is advisable for the\nisolation system made of curved surface sliders....
Loading....