scholarly journals Experiment on Interaction of Abutment, Steel H-Pile and Soil in Integral Abutment Jointless Bridges (IAJBs) under Low-Cycle Pseudo-Static Displacement Loads

2020 ◽  
Vol 10 (4) ◽  
pp. 1358 ◽  
Author(s):  
Fuyun Huang ◽  
Yulin Shan ◽  
Guodong Chen ◽  
Youwei Lin ◽  
Habib Tabatabai ◽  
...  
Keyword(s):  
Time History ◽  
Earth Pressure ◽  
Traditional Theory ◽  
Test Results ◽  
Integral Abutment ◽  
Horizontal Deformation ◽  
Soil Pressure ◽  
Significant Difference ◽  
Jointless Bridges ◽  
Pile Interaction

Soil-abutment or soil-pile interactions under cyclic static loads have been widely studied in integral abutment jointless bridges (IAJBs). However, the IAJB has the combinational interaction of soil-abutment and soil-pile, and the soil-abutment-pile interaction is lack of comprehensively study. Therefore, a reciprocating low-cycle pseudo-static test was carried out under an cyclic horizontal displacement load (DL) to gain insight into the mechanical behavior of the soil-abutment-pile system. Test results indicate that the earth pressure of backfill behind abutment has the ratcheting effect, which induced a large earth pressure. The soil-abutment-pile system has a favorable energy dissipation capacity and seismic behavior with relatively large equivalent viscous damping. The accumulative horizontal deformation in pile will be occurred by the effect of abutment and unbalance soil pressure of backfill. The test shows that the maximum horizontal deformation of pile occurs in the pile depth of 1.0b~3.0b of pile body rather than at the pile head due to the accumulative deformation of pile, which is significantly different from those of previous test results of soil-pile interaction. The time-history curve for abutment is relatively symmetrical and its accumulative deformation is small. However, the time-history curve of pile is asymmetrical and its accumulative deformation is dramatically large. The traditional theory of deformation applies only to the calculation of noncumulative deformation of pile, and the influence of accumulative deformation should be considered in practical engineering. A significant difference of inclinations in the positive and negative directions increases when the displacement load is relatively large. The rotation of abutment when bridge expands is larger than that when bridge contracts due to earth pressure of backfill.

scholarly journals Seismic Performance of Various Piles Considering Soil–Pile Interaction under Lateral Cycle Loads for Integral Abutment Jointless Bridges (IAJBs)

2020 ◽  
Vol 10 (10) ◽  
pp. 3406
Author(s):  
Fuyun Huang ◽  
Yulin Shan ◽  
Ahad Javanmardi ◽  
Xiaoye Luo ◽  
Baochun Chen
Keyword(s):  
Energy Dissipation ◽  
Plastic Hinge ◽  
Reinforcement Ratio ◽  
Effective Length ◽  
Deformation Capacity ◽  
Integral Abutment ◽  
Concrete Pile ◽  
Jointless Bridges ◽  
Pile Interaction ◽  
Energy Dissipation Capacity

The flexural pile foundation is used in integral abutment jointless bridges (IAJBs) in practical engineering to effectively dissipate the horizontal reciprocating deformation induced by the ambient temperature or earthquake loadings. Various types of flexural piles including the H-shaped steel pile (HP), prestressed concrete pile (PC), prestressed high-strength concrete pile (PHC) as well as the reinforcement concrete pile (RC) have been implemented in IAJBs. However, there is a lack of comprehensive studies on the flexural deformation and seismic performances of these piles. In order to investigate and compare their mechanical behaviors and seismic performances, a low-cycle pseudo-static test on several different types of piles was carried out. The test results indicated that the plastic hinge location of piles moved to a deeper pile depth with the increase of reinforcement ratio, buried pile depth and prestressing level, which led to better pile–soil interaction. The crack resistance of a concrete pile was improved as the reinforcement ratio and prestressing level increased. Moreover, the rectangular pile had a better soil–pile interaction and energy dissipation capacity than the circular pile. The inflection point of the pile deformation shifted deeper as reinforcement ratio, buried pile depth and prestressing level increased, which improved the effective length and horizontal deformation capacity of piles. The H-shaped steel pile showed a better elastic-plastic deformation capacity, ductility and energy dissipation capacity as compared to the concrete pile. Moreover, the pile having a higher bearing ratio sustained larger lateral loads whereas the surrounding soil was subjected to higher loads. Finally, new seismic design criteria of three-stage seismic fortification and five damage level for the concrete piles of IAJBs were proposed.

Study on Vertical Earth Pressure of Slab Culvert under High Embankment

2012 ◽  
Vol 256-259 ◽  
pp. 1898-1902 ◽  
Author(s):  
Bao Kuan Ning ◽  
He Fan ◽  
Lei Gong ◽  
Guo Qing Liu
Keyword(s):  
Numerical Simulation ◽  
Boundary Conditions ◽  
Field Test ◽  
Structural Design ◽  
Earth Pressure ◽  
Test Results ◽  
Soil Pressure ◽  
Vertical Earth Pressure ◽  
The Impact ◽  
Good Agreement

With the increasing of embankment culvert engineering applications, there has been due in part to the structural design is too conservative and not economic or select unreasonable structural form, leading to the phenomenon of cracking or even collapse of the culvert structure, and the phenomenon has seriously affected the normal use of the highway. In this paper, the numerical simulation of vertical earth pressure distribution on different structural forms of embankment on culverts, to discuss the impact of boundary conditions, fill height, the thickness of the culvert culverts vertical earth pressure. Combined with Heda highway a culvert covert field test results and numerical simulation results were compared and analyzed. The results show that the numerical simulation and field test results in good agreement with the culvert structure in the form of vertical earth pressure of the embankment culverts have a greater impact; the structure of different forms of the culvert in the upper soil pressure is significantly different. In addition, analysis of the impact of boundary conditions, filling height of culvert vertical earth pressure values. The results can reference for the study of the structural design of the embankment culverts security.

scholarly journals Analysis of Soil Pressure in Indoor Model Test of H-Typed Prestressed Concrete Bank Protection Pile

2021 ◽  
Author(s):  
Song Zheng
Keyword(s):  
Prestressed Concrete ◽  
Earth Pressure ◽  
Bending Moment ◽  
Test Results ◽  
Sheet Pile ◽  
Soil Pressure ◽  
Scaled Model ◽  
Concrete Piles ◽  
Pressure Calculation ◽  
Different Depths

In order to explore the distribution of soil pressure on the side of the pile and the bending moment of the pile body during the excavation and pile loading stages of the H-shaped prestressed concrete piles, three groups of indoor scaled model tests with prestressed rectangular piles and with or without prestressed H-shaped piles were carried out, and the test results shows that the lateral earth pressure on both sides of the sheet pile has the same trend as the static earth pressure calculation value when it is not excavated, but the measured earth pressure at different depths is always lower than the static earth pressure calculation value; in the excavation stage, the H-shaped prestressed pile lateral soil pressure on the side of the pile excavation is less than that of the rectangular sheet pile and the unprestressed H-typed pile.

Perbedaan sensitivitas tetes telinga antibiotik terhadap Pseudomonas aeruginosa pada otitis media supuratif kronik

2012 ◽  
Vol 42 (2) ◽  
Author(s):  
Anton Budhi Darmawan ◽  
Dwi Utami Anjarwati
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Otitis Media ◽  
Chronic Suppurative Otitis Media ◽  
Test Results ◽  
Sectional Study ◽  
Suppurative Otitis Media ◽  
Number Of Patients ◽  
Significant Difference ◽  
Cochran Test ◽  
Post Hoc

Background: Chronic suppurative otitis media (CSOM) is one infectious disease of the middle ear, most commonly caused by Pseudomonas aeruginosa. A high number of patients come to the ENT outpatient clinic with active benign type of CSOM. The bacteria Pseudomonas aeruginosa is capable of producing biofilm which protects itself from penetration of antibiotics, and therefore creates resistance towards antibiotics and difficult to eradicate. Objective: The aim of this study was to compare the sensitivity levels of chloramphenicol, polymyxin-neomycin, cyprofloxacin and ofloxacine against Pseudomonas aeruginosa in patients with active benign type CSOM in ENT clinic. Method: The method used was across sectional study on 25 patients, from August 2010 until December 2010. Samples were taken withear swab and then put on sensitivity test to chloramphenicol, polymyxin-neomycin, cyprofloxacin andofloxacine using the diffusion disc method. The analysis used in this study was Cochran test. Results: Results showed a significant difference in sensitivity among chloramphenicol (38,70%), polymyxinneomycin(83,87%),cyprofloxacin(90,32%)andofloxacin(58,06%)withp=0,000(p<0,05).PostHocanalysisusing the Mc Nemar indicated that there were significant differences in sensitivity betweenpolymyxin-neomycin to chloramphenicol with p=0,000 (p<0,05), ciprofloxacin to chloramphenicol andciprofloxacin to ofloxacine with p= 0,002, but there were no significant differences between cyprofloxacinto polymyxin-neomycin with p=0,687, polymyxin-neomycin to ofloxacin p=0.057 and ofloxacin tochloramphenicol p=0,109.   There were significant differences in antibiotic ear dropssensitivity to Pseudomonas aeruginosa in patients with active benign type of CSOM. Cyprofloxacin andpolymyxin-neomycin were more sensitive than ofloxacin and chloramphenicol. Keywords: Pseudomonas aeruginosa, active benign type of chronic suppurative otitis media, antibioticear drops.  Abstrak :  Latar belakang: Otitis media supuratif kronik (OMSK) merupakan penyakit infeksi kronik telinga tengah yang sering dijumpai di klinik THT. Penyebab tersering OMSK adalah bakteri Pseudomonasaeruginosa. Pseudomonas aeruginosa mempunyai kemampuan untuk membentuk biofilm yangmelindunginya dari penetrasi antibiotik sehingga menimbulkan resistensi terhadap antibiotik dan sulituntuk eradikasinya. Tujuan: Untuk mengetahui perbandingan tingkat sensitivitas kloramfenikol,polimiksin-neomisin, ciprofloksasin dan ofloksasin terhadap isolat Pseudomonas aeruginosa padapasien OMSK benigna aktif di klinik THT RSMS. Metode: Metode yang digunakan adalah crosssectional terhadap 29 pasien OMSK di klinik THT RSMS periode bulan Agustus 2010 - Desember2010. Pengambilan sampel dilakukan dengan swab telinga. Uji sensitivitas terhadap kloramfenikol,polimiksin-neomisin, ciprofloksasin dan ofloksasin dilakukan dengan metode cakram secara difusi.Analisis yang digunakan dalam penelitian ini adalah Cochran dan analisis post hoc. Hasil: Didapatkansensitivitas kloramfenikol sebesar 38,70%, polimiksin-neomisin sebesar 83,87%, ciprofloksasin sebesar90,32% dan ofloksasin sebesar 58,06% dengan p=0,01 (P<0,05), yang menunjukkan adanya perbedaansensitivitas yang bermakna antara kloramfenikol, polimiksin-neomisin, ciprofloksasin dan ofloksasinterhadap Pseudomonas aeruginosa. Analisis post hoc menggunakan Mc Nemar menunjukkan bahwaterdapat perbedaan sensitivitas yang bermakna antara tetes telinga polimiksin-neomisin terhadapkloramfenikol, dan ciprofloksasin terhadap kloramfenikol p=0,000 (p<0,05), serta terdapat perbedaanyang bermakna antara tetes telinga ciprofloksasin terhadap ofloksasin, p=0,002, tetapi tidak terdapatperbedaan yang bermakna antara ciprofloksasin terhadap polimiksin-neomisin, p=0,687, polimiksinneomisinterhadap ofloksasin p=0,057, dan kloramfenikol terhadap ofloksasin p=0,109. Kesimpulan:Terdapat perbedaan sensitivitas yang bermakna tetes telinga antibiotik terhadap Pseudomonas aeruginosa pada pasien OMSK benigna aktif. Ciprofloksasin dan polimiksin-neomisin tetes telinga mempunyai sensitivitas yang lebih baik dibanding ofloksasin dan kloramfenikol. Kata kunci: Pseudomonas aeruginosa, otitis media supuratif kronik, tetes telinga antibiotik 

A STUDY OF CONDYLAR POSITION IN CENTRIC RELATION AND MAXIMAL INTERCUSPATION USING CONEBEAM TOMOGRAPHY

2019 ◽  
pp. 84-92
Author(s):  
Anh Chi Phan ◽  
Xuan Anh Ngoc Ho
Keyword(s):  
Dental Students ◽  
Cone Beam ◽  
Test Results ◽  
Reference Position ◽  
Centric Relation ◽  
Temporomandibular Joints ◽  
Significant Difference ◽  
Mandibular Fossa ◽  
Condylar Position ◽  
Cone Beam Tomography

Background: The condylar position discrepancy between centric relation and maximal intercuspation has been still a controversial issue. Aims: To compare the condylar position between centric relation and maximal intercuspation using cone-beam tomography in patients without temporomandibular joints disorder. Materials and methods: To assess the condylar position in centric relation and maximal intercuspation using cone-beam tomography on 40 fifth-year and sixth-year dental students of Hue University of Medicine and Pharmacy without temporomandibular joints disorder. The condylar positions are assessed following Sener classification (2009) and are compared between centric relation and maximal intercuspation using pairedsamples t-test and Mann-Whitney U-test. Results: Among 480 condye-to-fossa measurement pairs, there are 91.2% pairs having difference between two reference position but there is no significant difference. The condylar position at the superior of mandibular fossa has the greatest percentage in both centric relation and maximal intercuspation (43.8% in centric relation and 51.2% in maximal intercuspation). This greatest percentage is followed by the condylar position at posterior of mandibular fossa (32.5% in centric relation and 36.3% in maximal intercuspation). Lastly, the condylar position at the anterior of mandibular fossa has the fewest percentage (23.7% in centric relation and 12.5% in maximal intercuspation). Conclusion: There is no significant difference of condylar position between centric relation and maximal intercuspation in patients without temporomandibular joints disorder. Key words: Condylar position, centric relation, maximal intercuspation, cone-beam tomography

Sinonasal effects of external dacryocystorhinostomy

2021 ◽  
pp. 1-4
Author(s):  
H Eyigor ◽  
E A Cetinkaya ◽  
D T Coban ◽  
G Ozturk ◽  
Ö Erdem
Keyword(s):  
Mucociliary Clearance ◽  
Nasal Symptom ◽  
Ciliary Activity ◽  
Test Results ◽  
Saccharine Test ◽  
Significant Difference ◽  
Symptom Scores ◽  
Endoscopic Score ◽  
External Dacryocystorhinostomy

Abstract Objective External dacryocystorhinostomy is thought to cause mucociliary dysfunction by damaging the mucosa, in turn affecting ciliary activity and mucus quality. This study investigated the effect of external dacryocystorhinostomy on sinonasal function. Methods Patients scheduled for unilateral external dacryocystorhinostomy who underwent endoscopic nasal examination and paranasal sinus computed tomography were included in this study. A saccharine test was performed on the planned surgical side and the mucociliary clearance time was determined. The sinonasal quality of life was measured in all patients, pre-operatively and at six months post-operatively, using the Sino-Nasal Outcome Test-22. The Lund–Kennedy endoscopic score was also determined in all patients, both pre- and post-operatively. Results The study comprised 28 patients (22 females and 6 males). A statistically significant difference was found between the pre- and post-operative saccharine test results (p = 0.006), but not between the pre- and post-operative Sino-Nasal Outcome Test-22 scores (p > 0.05). Conclusion This study is one of only a few to investigate the effect of external dacryocystorhinostomy on sinonasal function. The results showed that external dacryocystorhinostomy impairs mucociliary clearance. The surgical procedure is well tolerated and does not significantly change nasal symptom scores.

Earth pressures exerted on an induced trench cast-in-place double-cell rectangular box culvert

2012 ◽  
Vol 49 (11) ◽  
pp. 1267-1284 ◽  
Author(s):  
Olajide Samuel Oshati ◽  
Arun J. Valsangkar ◽  
Allison B. Schriver
Keyword(s):  
Earth Pressure ◽  
Test Results ◽  
Overburden Pressure ◽  
Centrifuge Testing ◽  
Geotechnical Centrifuge ◽  
Drag Forces ◽  
Field Instrumentation ◽  
Earth Pressures ◽  
Box Culvert ◽  
Base Contact

Earth pressure data from the field instrumentation of a cast-in-place reinforced rectangular box culvert are presented in this paper. The instrumented culvert is a 2.60 m by 3.60 m double-cell reinforced cast-in-place rectangular box buried under 25.10 m of fill constructed using the induced trench installation (ITI) method. The average earth pressure measured across the roof was 0.42 times the overburden pressure, and an average of 0.52 times the overburden pressure was measured at mid-height of the culvert on the sidewalls. Base contact pressure under the rectangular box culvert was also measured, providing field-based data demonstrating increased base pressure resulting from downward drag forces developed along the sidewalls of the box culvert. An average increase of 25% from the measured vertical earth pressures on the roof plus the culvert dead load (DL) pressure was calculated at the culvert base. A model culvert was also tested in a geotechnical centrifuge to obtain data on earth pressures at the top, sides, and base of the culvert. The data from the centrifuge testing were compared with the prototype structure, and the centrifuge test results agreed closely with the measured field prototype pressures, in spite of the fact that full similitude was not attempted in centrifuge testing.

Inter-Bolt Variability of Cotton Duck #4 and the Effects on Cigarette Ignition Propensity Test Outcome

1995 ◽  
Vol 13 (2) ◽  
pp. 127-140 ◽  
Author(s):  
Richard Jupe ◽  
Donald K. Shipley ◽  
William Z. Hudson ◽  
Joseph T. Wanna ◽  
Linda C. Greear
Keyword(s):  
Test Methods ◽  
Physical Parameters ◽  
Test Results ◽  
Astm Method ◽  
Significant Difference ◽  
Ignition Propensity

Two bolts of cotton duck fabric that meet military specifications and the purchasing guidelines described by the National Institute of Standards and Technology (NIST) for use as a substrate in "Test Methods for Quantifying the Propensity of Cigarettes to Ignite Soft Furnishings" were tested with smoldering cigarettes to determine the effect of inter-bolt variations on cigarette ignition propensity test outcome. The test was designed around an ASTM method that calls for the control of all known test variables, except for those inherent to the fabric's manufacture. The ignitability of each fabric was determined by testing two sets of 48 replications for each of two experimental cigarettes. The two bolts of cotton duck fabric showed a statistically significant difference in ignitions, independent of environmental and experimental fac tors. Two additional bolts of cotton duck #4 were analyzed. Cigarette ignition test results and the physical parameters of the additional bolts offer evidence that the NIST specifications are difficult to meet and further that test results are extremely sensitive to fabric properties.

KORELASI ANTARA HASIL TES MIKROSKOPIS DENGAN TES CEPAT MOLEKULER PADA PASIEN TUBERCULOSIS DAN MULTIDRUG RESISTEN TUBERCULOSIS DI RSUD Dr. H CHASAN BOESOIRIE TERNATE

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Andi Sitti Nur Afiah ◽  
Fera The
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Pulmonary Disease ◽  
Program Analysis ◽  
Rifampicin Resistance ◽  
Test Results ◽  
Chi Square ◽  
Significant Difference ◽  
Mdr Tb ◽  
Chi Square Test ◽  
Analytical Research

Tuberculosis (TB) is a pulmonary disease caused by Mycobacterium tuberculosis. Globally in 2018 theestimated number of people affected by TB was estimated at 10.0 million population and 484,000 cases ofmultidrug-resistant TB (MDR-TB). This study aims to determine the correlation between microscopic testresults with RMT on TB and MDR-TB patients at RSUD Dr. H Chasan Boesoirie Ternate. This type of researchis analytical research using a retrospective approach. The sample in this study were patients with suspected TBand MDR-TB who had performed microscopic tests and TCM in February – April at 2020 in the ClinicalPathology Laboratory of RSUD Dr. H Chasan Boesoirie Ternate, who met the inclusion and exclusion criteria.Data were analyzed using the SPSS program analysis was carried out in stages, namely by univariate andbivariate using chi-square test. From 100 samples, the results of RMT examination with TB suspects were 30rifampicin sensitive samples with 2 rifampicin resistance and 5 rifampin sensitive samples for TB MDR-TBsuspects RMT examination results. Chi-square test results obtained the value of p = 000 (p <0.05). There is stilla significant difference between the microscopic test results with RMT in TB and MDR-TB suspect patients atRSUD Dr. H Chasan Boesoirie Ternate.

Could Be % MMEF and sGaw Determinant Diagnostic Parameters Between Partial Reversibility and Reversibility in Evaluating Short-Acting Bronchodilator Response?

2021 ◽  
Author(s):  
Gökhan Erdoğan ◽  
Elif Altuğ ◽  
Sacide Rana Işık ◽  
Levent Tabak
Keyword(s):  
Independent Predictor ◽  
Binary Logistic Regression ◽  
Threshold Value ◽  
Test Results ◽  
Binary Logistic Regression Model ◽  
Bronchodilator Response ◽  
Significant Difference ◽  
Post Hoc ◽  
The Relationship ◽  
Airway Conductance

INTRODUCTION: By examining the relationship between changes in maximum mild-expiratory flow( MMEF) and specific airway conductance(sGaw), parameters with the change in FEV1 when evaluating the spirometer test and the bronchodilator response, we investigated their diagnostic contribution to the bronchodilator response in those with partial responses to FEV1. METHODS: The retrospective study sample consists of data from 112 patients between Jun 1, 2019, and Feb 1, 2020 who applied to the pulmonary function laboratory with a pre-diagnosis of bronchial hyperreactivity as well as body plethysmography test performed together with the reversibility test. RESULTS: MMEF% and ▲sGaw were linearly correlated with ▲FEV1 (respectively r = 0.752; p <0.001, r = 0.611; p <0.001). While there was a significant difference between ▲MMEF% and ▲sGaw between reversible, partially reversible, and irreversible groups (P <0.001), there was no significant difference in ▲sGaw between partial reversible and reversible groups in post-hoc comparisons (P> 0.05). In the binary logistic regression model created between the partially reversible and reversible groups, demographic characteristics, MMEF% and ▲sGaw variables, ▲MMEF was an independent predictor [OR: 1.132; 95% CI (1.036-1.238), p = 0.006]. The 24% threshold for absolute reversibility or partial reversibility calculated with MMEF% was significant, indicating significance at 86.2% sensitivity and 80.8% specificity (AUC: 0.811, 95% CI: 0.686-0.936; p <0.001). This value we found defined 81% of the partially reversible group as reversible. DISCUSSION AND CONCLUSION: We observed that ▲sGaw alone didn' have a determinant contribution for determining reversibility in bronchodilator response, which showed partial reversibility with respect to FEV1 change. We believe that ▲MMEF% can be an independent predictor between these two groups and the calculated threshold value of 24% can be used as a criterion for determining the reversibility in cases where FEV1 is not determinant.

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