scholarly journals Comparative assessment of the safety of lighting pillars installed near the road under the action of a car driving over them

2018 ◽  
Vol 5 (4) ◽  
Author(s):  
Ilya Ovchinnikov ◽  
Rafail Garibov ◽  
Igor Ovchinnikov
Keyword(s):  
Reinforced Concrete ◽  
Comparative Assessment ◽  
Design Parameters ◽  
Vehicle Speed ◽  
Bending Moments ◽  
Shear Forces ◽  
Vehicle Collisions ◽  
Small Deviations ◽  
The Road ◽  
Car Driving

The task of the comparative evaluation of the safety lighting poles installed around the road under the action hit them the car. Notes that studies on the calculation and modeling lighting poles when exposed to shock loads due to vehicle collisions is very small. The situation of a conditional vehicle exit (LADAPRIORASEDAN) from the carriageway to the roadside is followed up, followed by a collision with a metal or reinforced concrete support for external electric lighting. Vehicle speed is 60 km/h and the calculation is performed by finite element method. Diagram shows the compressive forces, bending moments, shear forces, displacements. The analysis found that by hitting the conditioned car to support the outer electrical lighting in a bearing of reinforced concrete arise effort close to being admitted that for small deviations from design parameters (e.g., speed limit is exceeded, possible defects and injuries of lighting columns) can lead to the collapse construction, including the possible fall of its vehicle. Consequently, the support of the metal outer lighting when hit by the vehicle conditional security parameters and external lighting strength of reinforced concrete is preferred support.

scholarly journals RESEARCH OF THE INFLUENCE OF LONGITUDINAL COMPRESSION ON THE STRENGTH OF THE WALL OF TWO-TURNED REINFORCED CONCRETE ELEMENTS WITH A CHARACTERISTIC EPURA BENDING MOMENTS IN THE AREA OF ACTION OF LATERAL FORCES

2021 ◽  
Vol 3 (72) ◽  
pp. 34-37
Author(s):  
A. Abdullaev .
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Experimental Studies ◽  
Compressive Force ◽  
Reinforced Concrete Beams ◽  
Bending Moments ◽  
Shear Forces ◽  
Longitudinal Compression ◽  
Lateral Forces ◽  
Concrete Elements

Experimental studies have been carried out to study the effect of longitudinal compression on the strength of the wall of I-beams of reinforced concrete beams.It has been established that with the central application of a longitudinal compressive force, the strength of the wall of I-beams of reinforced concrete beams with an alternating diagram of bending moments in the zone of action of transverse forces practically depends little on the degree of longitudinal compression.A comparative analysis of the results obtained with the results of similar experimental studies carried out on I-beam reinforced concrete beams with an unambiguous diagram of bending moments in the zone of action of shear forces is carried out.

scholarly journals EXPERIMENTAL AND ANALYTICAL COMPARISON OF TORSION, BENDING MOMENT AND SHEAR FORCES IN REINFORCED CONCRETE BEAMS USING BS 8110, EURO CODE 2 AND ACI 318 PROVISIONS

2017 ◽  
Vol 36 (3) ◽  
pp. 705-711
Author(s):  
CP Amulu ◽  
CA Ezeagu
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Testing Machine ◽  
Bending Moment ◽  
Reinforced Concrete Beams ◽  
Bending Moments ◽  
Shear Forces ◽  
Combined Loads ◽  
Angle Crack ◽  
Set Up

This study investigated the effect of combined actions of torsional moments, bending moments and shear forces in reinforced concrete beams with concrete compressive strength of 30N/mm2.The ultimate torsional moments, bending moments, and shear forces of the beams were determined experimentally, through a simple test arrangement set-up on fifteen beam specimens grouped from BC1 to BC5, three beam specimens in each group. The combined loads were induced by loading the test beams at an eccentricity of  from the beam’s principal axis at the mid-span, using Computerized Universal Testing Machine TUE-C-100. BS 8110, Euro code 2 and ACI 318 were used to calculate the ultimate torsional moments provided by both longitudinal and transverse reinforcements, bending moments and shear forces induced. The values obtained from the codes were compared with those of experimental results for validation. It was observed that Eurocode 2 predicted the highest bending moment of 21.1530kNm, the highest torsional moments of 9.8470kNm and 12.6193kNm, for torsional resistance provided by longitudinal and transverse reinforcements respectively, at an angle crack of 45°, while BS 8110 predicted the least values. ACI 318 predicted the highest value of internal shear forces that the beams possessed before yielding to the applied loads. http://dx.doi.org/10.4314/njt.v36i3.7

Calculation of Grillage Strip Foundation in Area of Karst Collapses Formation

2015 ◽  
Vol 770 ◽  
pp. 723-728 ◽  
Author(s):  
Ruslan V. Sharapov ◽  
Nina D. Lodigina
Keyword(s):  
Calculation Scheme ◽  
Design Parameters ◽  
Karst Collapse ◽  
Bending Moments ◽  
Strip Foundation ◽  
Shear Forces ◽  
Unresolved Question

Now the most pressing and to end unresolved question is the determination of the design parameters for the base in the conditions of formation of karst deformations. Foundation calculations made on the basis of forecasting karst manifestations sizes and the likelihood of their formation at the base of the designed construction. In paper presented the grillage calculation scheme. We calculated the grillage with four bays for four cases: excluding karst collapse, taking into account the collapse of a single support, taking into account the collapse under two not adjacent supports and taking into account the collapse at two adjacent supports. In paper presents the diagrams of bending moments and shear forces.

Numerical analysis of I-Lam honeycomb sandwich panels for collision protection of reinforced concrete beams

2016 ◽  
Vol 19 (4) ◽  
pp. 497-522 ◽  
Author(s):  
Shi Cheng ◽  
Pizhong Qiao ◽  
Fangliang Chen
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Transportation Network ◽  
Core Layer ◽  
Field Application ◽  
Reinforced Concrete Beams ◽  
Design Parameters ◽  
Vehicle Collisions ◽  
Honeycomb Sandwich ◽  
Parametric Studies

Bridge damage due to over-height vehicle collisions is a major issue throughout the transportation network with damages ranging from minor distortion or spalling in fascia girders to almost complete bridge destruction. Repairing such damages resulted from over-height vehicle collisions is expensive, and it includes costs for bridge repair, and rerouting traffic as well as indirect economic and societal costs. In this study, in correlation with a series of impact tests for reinforced concrete beams with or without Impact-Laminate (I-Lam) panel protection by a wooden projectile, the numerical modeling using the finite element codes ABAQUS is conducted to simulate the over-height vehicle impact, and a good agreement with the available experimental data is obtained. Parametric studies are conducted to further investigate the effects of design parameters (e.g. the velocity of projectile, I-Lam parameters, and core layer sequence, etc.) on the effectiveness of the protection system. The observed phenomena from the parametric studies reflect a design philosophy aiming at improving protection efficiency and providing important information on design of I-Lam honeycomb sandwich collision protection systems for field application.

Coupling Impacts of Spray and Rainfall on Road Visibility and Vehicle Speeds: A Simulation-based Analysis

2021 ◽  
Author(s):  
Shuyi Wang ◽  
Tianheng Chen ◽  
Bin Yu ◽  
Yue Sun ◽  
Xiaochun Qin
Keyword(s):  
High Speed ◽  
Traffic Accidents ◽  
Water Film ◽  
Design Parameters ◽  
Vehicle Speed ◽  
Highway Design ◽  
The Road ◽  
Sight Distance ◽  
Rain Medium ◽  
Stopping Sight Distance

Impaired visibility resulting from rainfall contributes greatly to the occurrence of traffic accidents. This study presents a numerical simulation approach to analyze the extent to which the coupling of spray and raindrops reduces visibility and thus proposes safe speeds against inadequate visibility. The spray-raindrop coupling particles were modeled by considering the real highway design parameters and rainfall conditions. The road visibility was estimated through simulating the multiple scattering process of taillights in the spray-rain medium, and the maximum safe speed against inadequate visibility was then derived by comparing the visibility with the required stopping sight distance. Results show that: 1) either a high speed of the front truck or a thick water-film results in a significant reduction in road visibility and the maximum safe speed of the ego vehicle, 2) front vehicle speed plays a more important role in visibility reduction than the water-film thickness does.

EXPERIMENTAL STUDIES OF REINFORCED CONCRETE STRUCTURES WITH CROSS-SHAPED SPATIAL CRACK UNDER TORSION WITH BENDING

2020 ◽  
Vol 92 (6) ◽  
pp. 13-25
Author(s):  
Vl.I. KOLCHUNOV ◽  
◽  
A.I. DEMYANOV ◽  
M.M. MIHAILOV ◽  
◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Experimental Determination ◽  
Calculation Method ◽  
Experimental Studies ◽  
Concrete Structures ◽  
Design Parameters ◽  
Reinforced Concrete Structures ◽  
Experimental Scheme

The article offers a method and program for experimental studies of reinforced concrete structures with cross-shaped spatial crack under torsion with bending, the main purpose of which is to check the design assumptions and experimental determination of the design parameters of the proposed calculation method. The conducted experimental studies provide an opportunity to test the proposed calculation apparatus and clarify the regularities for determining deflections, angles of rotation of extreme sections, and stresses in the compressed zone of concrete. For analysis, the article presents a typical experimental scheme for the formation and development of cracks in the form of a sweep, as well as characteristic graphs of the dependence of the angles of rotation of end sections.

scholarly journals Smartphone monitoring of in-ambulance vibration and noise

2021 ◽  
pp. 095441192098599
Author(s):  
Tom Partridge ◽  
Lorelei Gherman ◽  
David Morris ◽  
Roger Light ◽  
Andrew Leslie ◽  
...  
Keyword(s):  
Transport Systems ◽  
Vertical Acceleration ◽  
Vehicle Speed ◽  
Noise Levels ◽  
The Road ◽  
Neonatal Transport ◽  
Mass Data ◽  
Transport Team ◽  
Vertical Accelerations ◽  
Noise Vibration

Transferring sick premature infants between hospitals increases the risk of severe brain injury, potentially linked to the excessive exposure to noise, vibration and driving-related accelerations. One method of reducing these levels may be to travel along smoother and quieter roads at an optimal speed, however this requires mass data on the effect of roads on the environment within ambulances. An app for the Android operating system has been developed for the purpose of recording vibration, noise levels, location and speed data during ambulance journeys. Smartphone accelerometers were calibrated using sinusoidal excitation and the microphones using calibrated pink noise. Four smartphones were provided to the local neonatal transport team and mounted on their neonatal transport systems to collect data. Repeatability of app recordings was assessed by comparing 37 journeys, made during the study period, along an 8.5 km single carriageway. The smartphones were found to have an accelerometer accurate to 5% up to 55 Hz and microphone accurate to 0.8 dB up to 80 dB. Use of the app was readily adopted by the neonatal transport team, recording more than 97,000 km of journeys in 1 year. To enable comparison between journeys, the 8.5 km route was split into 10 m segments. Interquartile ranges for vehicle speed, vertical acceleration and maximum noise level were consistent across all segments (within 0.99 m . s−1, 0.13 m · s−2 and 1.4 dB, respectively). Vertical accelerations registered were representative of the road surface. Noise levels correlated with vehicle speed. Android smartphones are a viable method of accurate mass data collection for this application. We now propose to utilise this approach to reduce potential harmful exposure, from vibration and noise, by routing ambulances along the most comfortable roads.

scholarly journals Cortical Activity Linked to Clocking in Deaf Adults: fNIRS Insights with Static and Animated Stimuli Presentation

2021 ◽  
Vol 11 (2) ◽  
pp. 196
Author(s):  
Sébastien Laurent ◽  
Laurence Paire-Ficout ◽  
Jean-Michel Boucheix ◽  
Stéphane Argon ◽  
Antonio Hidalgo-Muñoz
Keyword(s):  
Near Infrared ◽  
Brain Activity ◽  
Time Estimation ◽  
Cognitive Effort ◽  
Deaf People ◽  
Vehicle Speed ◽  
Neural Basis ◽  
Functional Near Infrared Spectroscopy ◽  
The Road ◽  
Deaf Adults

The question of the possible impact of deafness on temporal processing remains unanswered. Different findings, based on behavioral measures, show contradictory results. The goal of the present study is to analyze the brain activity underlying time estimation by using functional near infrared spectroscopy (fNIRS) techniques, which allow examination of the frontal, central and occipital cortical areas. A total of 37 participants (19 deaf) were recruited. The experimental task involved processing a road scene to determine whether the driver had time to safely execute a driving task, such as overtaking. The road scenes were presented in animated format, or in sequences of 3 static images showing the beginning, mid-point, and end of a situation. The latter presentation required a clocking mechanism to estimate the time between the samples to evaluate vehicle speed. The results show greater frontal region activity in deaf people, which suggests that more cognitive effort is needed to process these scenes. The central region, which is involved in clocking according to several studies, is particularly activated by the static presentation in deaf people during the estimation of time lapses. Exploration of the occipital region yielded no conclusive results. Our results on the frontal and central regions encourage further study of the neural basis of time processing and its links with auditory capacity.

scholarly journals Numerical Modelling of Reinforced Concrete Slender Walls Subjected to Coupled Axial Tension–Flexure

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Xiaowei Cheng ◽  
Haoyou Zhang
Keyword(s):  
Reinforced Concrete ◽  
Plastic Hinge ◽  
Element Model ◽  
Lateral Loading ◽  
Design Parameters ◽  
Seismic Behaviour ◽  
High Rise ◽  
Ultimate Deformation ◽  
Axial Tension ◽  
Plastic Hinge Length

AbstractUnder strong earthquakes, reinforced concrete (RC) walls in high-rise buildings, particularly in wall piers that form part of a coupled or core wall system, may experience coupled axial tension–flexure loading. In this study, a detailed finite element model was developed in VecTor2 to provide an effective tool for the further investigation of the seismic behaviour of RC walls subjected to axial tension and cyclic lateral loading. The model was verified using experimental data from recent RC wall tests under axial tension and cyclic lateral loading, and results showed that the model can accurately capture the overall response of RC walls. Additional analyses were conducted using the developed model to investigate the effect of key design parameters on the peak strength, ultimate deformation capacity and plastic hinge length of RC walls under axial tension and cyclic lateral loading. On the basis of the analysis results, useful information were provided when designing or assessing the seismic behaviour of RC slender walls under coupled axial tension–flexure loading.

scholarly journals The implications of vehicle collisions for the Endangered endemic Zanzibar red colobus Piliocolobus kirkii

Oryx ◽  
2021 ◽  
pp. 1-9
Author(s):  
Harry Olgun ◽  
Mzee Khamis Mohammed ◽  
Abbas Juma Mzee ◽  
M. E. Landry Green ◽  
Tim R. B. Davenport ◽  
...  
Keyword(s):  
Road Ecology ◽  
Local Population ◽  
Red Colobus ◽  
Vehicle Collisions ◽  
The Road ◽  
Life History Data ◽  
Natural Predation ◽  
Historical Accounts ◽  
The Impact

Abstract Roads affect wildlife in a variety of negative ways. Road ecology studies have mostly concentrated on areas in the northern hemisphere despite the potentially greater impact of roads on biodiversity in tropical habitats. Here, we examine 4 years (January 2016–December 2019) of opportunistic observations of mammalian roadkill along a road intersecting Jozani-Chwaka Bay National Park, Unguja, Zanzibar. In particular, we assess the impact of collisions on the population of an endemic primate, the Endangered Zanzibar red colobus Piliocolobus kirkii. Primates accounted for the majority of roadkill in this dataset. Monthly rainfall was not associated with roadkill frequency for mammals generally, nor for the Zanzibar red colobus. No single age–sex class of colobus was found dead more often than expected given their occurrence in the local population. The overall effect of roadkill on colobus populations in habitats fragmented by roads is unknown given the lack of accurate, long-term life history data for this species. Our findings suggest that mortality from collisions with vehicles in some groups of colobus is within the range of mortality rates other primates experience under natural predation. Unlike natural predators, however, vehicles do not kill selectively, so their impact on populations may differ. Although a comparison with historical accounts suggests that the installation of speedbumps along the road near the Park's entrance has led to a significant decrease in colobus roadkill, further actions to mitigate the impact of the road could bring substantial conservation benefits.

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