Real Time Photogrammetric Monitoring Of Bridges

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2014Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2014Bu çalışmada yapısal deformasyonda gerçek zamanlı fotogrametrik izlemelerin sonuçları sunulmaktadır. Bu amaçla belirlenen bir akış çerçevesinde; uygun kamera lens setinin belirlenmesi, izleme ve hedef noktalarının konumlarının belirlenmesi, kamera kalibrasyonları, tasarlanan sistemin kapalı alan testleri, test alanı olarak seçilen köprünün ölçmeleri ve fotogrametrik değerlendirme adımları izlenmiştir. Çalışma süresince, eş zamanlı görüntü elde etme ve fotogrametrik değerlendirme aşamalarında kullanılmak üzere yapılan bütün programlamalar Matlab programlama dilinde geliştirilmiştir. İlk kapalı alan testi için ITÜ Geomatik Mühendisliği Bölümü Laboratuvarında salınımını gözlemek üzere bir sarkaç ile çalışılmıştır. İkinci kapalı alan testinde; kimyasal ankrajlarla betona gömülmüş demir donatıların eksen boyunuca uygulanan çekme yükü altında yer değiştirmelerinin izleme ve fotogrametrik değerlendirme ile belirlenmesi hedeflenmiştir. Çalışmanın temel amacını oluşturan köprü hareketlerinin gözlemlenmesi için Fatih Sultan Mehmet Köprüsü çalışma alanı olarak kullanılmıştır. Çalışmada; köprü alt yüzeyinde ışık yayan diyotlar (LED) ile oluşturulan hedef ağı; endüstriyel video kamera verileri ile izlenmiş ve elde edilen veri setlerinden köprünün deplasmanları analiz edilmiştir.This thesis presents the results of real-time photogrammetric monitoring of the structural deformations. For this purpose, a schedule that contains determining convenient camera-lens set, designing monitoring and target locations, camera calibration, indoor tests of the designed system, onsite measurements of the selected bridge and photogrammetric evaluation steps was followed. A self-developed Matlab code was used for synchronous image acquisition and photogrammetric evaluation. For the first indoor test a pendulum, established at the laboratory of Geomatics Engineering Department of ITU, monitored in order to observe its oscillation. For the second indoor test it is aimed to determine the displacements of steel reinforcements, embedded into concrete by using chemical anchorages, while applying axial pulling loads by means of monitoring and photogrammetric evaluation. Second Bophorus Bridge was selected as the main study object that to be monitored and analysed. A target network created by Light Emitting Diodes (LED) was monitored by still video cameras and bridge displacement analysed by acquired data sets.DoktoraPh

Photogrammetric deformation monitoring of the second Bosphorus Bridge in Istanbul

Improving the efficiency of bridge inspection and minimizing the impact of dynamic load on the long term deterioration of the bridge structure reduces maintenance and upkeep costs whilst also improving bridge longevity and safety. This paper presents the results of an on-going project whose ultimate goal is the real-time photogrammetric monitoring the structural deformations of the second Bosphorus Bridge of Istanbul.Publisher's Versio

Determining pull - out deformations of bonded metal anchors embedded in concrete by means of photogrammetry

Chemical anchorages are applied in many engineering implementations, particularly strengthening of reinforced concrete structures. During strengthening procedure; chemical anchorages should be tested, since they supply to transfer the load between existing construction elements and newly added elements. Therefore; the study of the quality of chemical anchorages is an important issue in construction materials science. In this context; the most important experiment is to determine the pull-out loads of embedded anchorage reinforcement by applying axial loads. In this study; it is aimed to determine the displacements of steel reinforcements, embedded into concrete by using chemical anchorages, while applying axial pulling loads. In order to determine the displacements and load - deformation graphs; starting conditions and every 10 bar pressure applied conditions of the steel reinforcements were captured by the cameras. The obtained images were evaluated by using photogrammetric software. Based on the photogrammetric post-processing results, the load - deformation graphs were plotted and the loads at loss of adhesion were determined.Publisher's Versio

Investigation of the Treatment Efficiency of Biofilters in Terms of Odorous Gases Originated from Animal Breeding

Çalışmada hayvan çiftliklerinden kaynaklanan ve amonyak içeren kokulu atık gazların biyofiltrelerlearıtılması araştırılmıştır. Biyofiltreler, düşük enerji gereksinimleri ve ilk kurulum maliyetinin düşüklüğünedeniyle koku kontrolünde tercih edilmektedir. Bu nedenle, çalışmada hayvan barınaklarının aralıklıhavalandırma uygulamasının simüle edilmesi için kesikli düzenle kurulan laboratuvar ölçekli reaktörlerkullanılmıştır. Seri bağlı iki adet reaktöre kirletici olarak, konsantre amonyum hidroksit çözeltisinden havageçirmek suretiyle ile sıyrılarak elde edilen amonyak/hava karışımları beslenmiştir. Filtrelerde dolgumaddesi olarak evsel katı atıktan üretilmiş kompost ve odun talaşı karışımı kullanılmıştır. Farklı yüklemeoranlarına karşılık amonyağın biyofiltrelerde aerobik-biyolojik olarak oksidasyon verimi ve bu verimietkileyen faktörler incelenmiştir. Aklimasyon dönemi dahil 130 günlük süre içinde 1,32-27 g NH3/m3.saataralığında 8 farklı değerde yükleme yapılmış, ortalama amonyak giderim verimi % 97,2±1,8 olarakbulunmuştur.In the study, treatment of odorous waste gases emited from the cattle and sheep breeding facilities and poultry farms which containing ammonia were investigated by means of biofilters. Biofilters are preferred for odor control due to their low energy requirement and capital cost. For this purpose, bench scale batch reactors, were used to simulate the intermittent ventilation of animal barns. Ammonia/air mixtures used as pollution source were obtained by stripping the concentrated ammonium hydroxide via air and fed to two serially connected biofilter modules. Compost produced from domestic solid waste and sawdust mixture was used as a packing material in the filters. Factors affecting aerobic-biologic oxidation of ammonia in biofilters were investigated for different loading rates. During the 130 days which including the acclimation period, 8 different loads were loaded in the range of 1.32-27 g NH3/m3.h and the average ammonia removal rate was found as 97.2% ± 1.8

Finite element modeling and operational modal analysis of a historical masonry mosque

All rights reserved. Finite Element Modeling (FEM) and Operational Modal Analysis (OMA) is herein presented for the historical masonry Kütahya Kurşunlu Mosque within the framework of its seismic performance assessment. The historical structure is located in Turkey which has a high-level seismic activity. A FEM strategy was adopted to construct a numerical model of the structure considering a simplified three-dimensional geometry and a macro-modeling approach for the masonry. A representative numerical model of the existing structure was calibrated and improved according to the OMA results obtained from ambient vibration measurements, performed in-situ. The ambient vibration measurements were operated by using two triaxial accelerometers, that one of the accelerometers was regulated as a reference station whereas the other accelerometer was relocated to seven different points on the top of the walls. Identification of the experimental modal parameters was achieved by performing two different signal processing methodologies, namely the Enhanced Frequency Domain Decomposition (EFDD) and the Stochastic Subspace Identification - Unweighted Principal Components (SSI-UPC). Results obtained from both methods were compared in terms of the Modal Assurance Criterion (MAC) which considers the mode shapes derived in a specific range of frequency. The SSI-UPC method was employed in achieving the experimental modal response of the structure and the results were compared with the eigenvalue analysis results of the preliminary numerical model. A calibration process was carried out in terms of minimizing the difference between the experimental and numerical modal response by a trial and error approach and an average error of 4.9% was calculated for the modal frequencies of the first four global modes of vibration.- (undefined

Karadeniz Bölgesi'nde ayrışmış tüfitte heyelan stabilizasyonu.

A landslide occurred during the construction of the Giresun ا Espiye road between Km: 1+030 ا 1+170 in April 2003. Investigating the causes and mechanism of this slope failure along with suggesting a proper stabilization technique is aimed in this study. For that purpose, a detailed site investigation study, including engineering geological mapping, drilling work, in situ and laboratory tests, was performed. Weathered tuffite, tuffite, flysch and dacitic tuffite, from top to bottom, are the major units in the study area. A أtranslational slideؤ occurred in completely weathered tuffite owing to the disturbance of the stability of the slope by the excavations performed at the toe of the slope; particularly the foundation excavation for the restaurant building and for the road cut for the Giresun ا Espiye road. After establishing the model of the landslide in detail, shear strength parameters of the failure surface were determined by the back analysis method as "cohesion"=2.5 kN/m2 and "friction angle"=9°. Toe buttressing, ground water and surface water drainage options were considered for stabilizing the slope. For the back analysis calculations, the Morgenstern-Price and Spencer methods were used with the aid of the SLOPE/W computer program.M.S. - Master of Scienc

Edremit jeotermal sahasının jeokimyasal değerlendirmesi ve kavramsal modellemesi.

Edremit geothermal field with 42-62 °C discharge temperatures is utilized for space heating. Alternation of permeable and impermeable units created two superimposed aquifers in the area: upper unconfined and lower confined. Water samples from 21 (hot, warm, cold) wells were taken in this study. 8 of these wells penetrate the deeper confined, while 13 penetrate the shallower unconfined aquifer. Geochemical analysis revealed Na+K–SO4 nature for the hot (>40°C), Ca–HCO3 nature for the cold (<30°C) and Ca–SO4 nature for the warm (30-40°C) waters. δ18O-δD compositions point to a meteoric origin for all waters, while 14C analyses suggest longer subsurface residence times for the hot, compared to the cold/warm waters. Chemical and isotopic compositions indicate that “mixing” and “water-rock interaction” are the possible subsurface processes. When silica and cation geothermometers are evaluated together with fluid mineral equilibria calculations, a 110°C reservoir temperature is expected in the field. Saturation indices indicate potential silica scaling for waters at temperatures lower than discharge temperatures. Hydrogeology of the study area is highly affected by faults. The groundwater is percolated (down to 3 km depth) via deep seated step faults, heated at depth and ascends to surface at the low lands, especially through intersection of buried, mid-graben faults. During its ascent towards surface, geothermal water invades the two superimposed aquifers and mixing between hot and cold waters takes place in the aquifers. Resource assessment studies suggest a 3.45x1013 kJ accessible resource base and 9.1 MWt recoverable heat energy for Edremit geothermal field with 90% probability.Ph.D. - Doctoral Progra

Türkiye'deki tipik karayolu köprülerinin kırılganlık eğrileri ile sismik zarar görebilirliğinin belirlenmesi.

Recent devastating earthquakes revealed that bridges are one of the most vulnerable components of the transportation systems. These seismic events have emphasized the need to mitigate the risk resulting from the failure of the bridges. Depending on the seismicity of the bridge local site, seismic vulnerability assessment of the bridges can be done based on the fragility curves. These curves are conditional probability functions which give the probability of a bridge attaining or exceeding a particular damage level for an earthquake of a given intensity level. In this dissertation, analytical fragility curves are developed for the ordinary highway bridges in Turkey constructed after the 1990s to be used in the assessment of their seismic vulnerability. Bridges are first grouped into certain major bridge classes based on their structural attributes and sample bridges are generated to account for the structural variability. Nonlinear response history analyses are conducted for each bridge sample with their detailed 3-D analytical models under different earthquake ground motions having varying seismic intensities. Several engineering demand parameters are employed in the determination of seismic response of the bridge components as well as defining damage limit states in terms of member capacities. Fragility curves are obtained from the probability of exceeding each specified damage limit state for each major bridge class. Skew and single-column bent bridges are found to be the most vulnerable ones in comparison with the other bridge classes. Developed fragility curves can be implemented in the seismic risk assessment packages for mitigation purposes.Ph.D. - Doctoral Progra