"Inventi Impact: Civil Structures" 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. The 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.
In this research, the plate embedded parts and grooved embedded parts reinforced concrete structures were investigated. Two
types of plate embedded parts and three types of grooved embedded parts experienced coating treatment to enable sustainable
function. Later, the ultimate failure capacity by bending experiments was conducted and compared with the theoretically
calculated results. Moreover, three grooved embedded parts were simulated by ABAQUS to compare the results with the experimental
exploration results, which was in close agreement with the theoretically calculated results and finite element analysis
results. )e result indicated that the failure modes of the embedded specimens under the five working conditions are all concrete
vertebral failure. )e plate-type embedded components were proved to exhibit higher ultimate bearing capacity than the grooved
embedded parts. Moreover, the flexural and shear capacity of these five types of embedded parts has not been fully developed. )e
ultimate flexural and shear capacity of these five types of embedded parts could be further explored by adjusting the higher
.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....
The safe thickness of concrete retaining walls for curtain grouting on tunnel faces is an
essential factor related to tunnel safety and grouting effects. In this research, the concrete retaining
wall was simplified into a standard rectangular slab structure. The Rankine active earth pressure
theory and the plastic hinge theory were used to analyze the lateral force of the concrete retaining
wall. By deriving the safety‐thickness equation of the concrete retaining wall, a quantitative criterion
that can display the mechanism of the concrete retaining wall was obtained. The traditional empirical
formula and Kalmykov formula had a particular connection with the method in this paper in
determining the safe thickness of the concrete retaining wall. This was negatively related to the
compressive (tensile) strength of the concrete and the groundwater level and positively associated
with the buried depth of the tunnel. The conversion relationship between the traditional empirical
formula and the theoretical formula was established, and the exact solution formula for the value of
safety coefficient K0 was given. Finally, the rationality of the theoretical formula was verified by a
field test, in novel work that provides a reference for similar projects....
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 Zagreb 2020 earthquake severely damaged the historic centre of the city. Most of the
damage occurred on historic masonry residential buildings, many of which are situated very close to
the tram track. Although traffic-induced vibrations generally do not affect surrounding buildings,
they can be harmful to buildings damaged by a previous earthquake. Vibrations could contribute
to the further propagation of existing cracks. The effect of vibrations depends on many factors, one
of the most important being the distance between the track and the building. The vibrations are
highest at the source, and the energy loss occurs due to transfer through the soil to the recipients.
The impact of tram-induced vibrations on earthquake-damaged buildings in the city of Zagreb is
investigated in this paper. The analysis is conducted on a tramway network scale to identify critical
locations by performing continuous monitoring on the tramway network and risk analysis based
on the distance of buildings from the track, vibration amplitude at source, and building damage.
Further investigation is based on the level of buildings to evaluate the influence of vibrations on
actual buildings damaged in the Zagreb earthquake. Based on detailed signal analysis, the vibration
characterization is performed, and the influence on damaged masonry buildings is evaluated....
The U-shaped steel support has good surface protection and is one of the main supporting forms of the roadway under rock bursts.
However, in the supporting process of roadways under rock burst, there are poor mechanical properties of lap joints, resulting in a
serious decline in the anti-impact performance of U-shaped steel supports. Using a combination of laboratory experiments and
theoretical analysis, we study the sliding mechanism of the U-shaped steel bracket’s overlap section bearing and find the key
factors affecting the sliding performance of the overlap section. The characteristics of deformation and failure of U-shaped steel
supports under impact loads are analyzed by numerical calculations. An improved method for optimizing the sliding performance
of the lap section is proposed to provide theoretical support for the design of stable and constant-resistance energy-absorbing Oshed
supports. The research results show that the frictional properties between the contact surfaces of the overlapped sections,
especially the frictional properties between the contact surfaces of the clamp and the U-shaped steel, determine the sliding
characteristics of the U-shaped steel overlapped sections, which are the key factors affecting the bearing capacity of the support.
The single-point maximum bearing capacity of the U-shaped steel bracket under the uniformly distributed impact load is basically
close to the maximum bearing capacity of the U-shaped steel bracket under the concentrated impact load. When the U-shaped
steel bracket is uniformly loaded, its bearing capacity can be increased several times. When a gasket is added between the U-section
steel and the clamping bolt in the lap section, the bearing capacity changes smoothly during the sliding process, which greatly
improves the friction performance between the contact surfaces, and can greatly improve the overall bearing capacity, energy
absorption, and anti-impact performance of the support structure. Based on this, a stable and constant energy-absorption O-type
shed structure for the impacted underground roadway in Laohutai Mine was proposed. The field application proved that
improving the sliding performance at the joint of the U-shaped steel support can effectively control the deformation of the
roadway under the impact load....
� Copyright©2013. Inventi Journals Pvt.Ltd. All Right Reserved.