Validation Of A New Method For Determining The Remaining Service Life Of Rigid Pavements

About a half of the Austrian highways are rigid pavement constructions, and increasingly more money has to be invested in their renovation and redevelopment. However, there are different approaches for the evaluation of the condition assessment of concrete pavements. The aim of the research presented in this paper is a concept for assessing the condition of a road section in rigid pavement. This consists of a structural and a visual assessment scheme for selecting appropriate maintenance actions. For the verification of this new method of assessment of the structural condition of concrete pavements, several field tests were examined. Furthermore, a case study was carried out to examine the level of influence of several input parameter. This analysis shows that the influence of the layer thickness is very high, while the influence of the modulus of elasticity of the existing concrete is significant lower. The FWD measurements were carried out radial (instead of linear) for the first time. The results show possible inhomogeneities in the subgrade or in the bedding, which would not be recognized by the standard linear measurements. With the results from the already mentioned measurements, the remaining service life of the test tracks could be calculated.

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A mechanistic empirical approach for the evaluation of the structural capacity and remaining service life of flexible pavements at the network level

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2016-0060 ◽

2016 ◽

Vol 43 (8) ◽

pp. 749-758 ◽

Cited By ~ 6

Author(s):

Mofreh Saleh

Keyword(s):

Service Life ◽

Compressive Strain ◽

Simulated Data ◽

Structural Condition ◽

Remaining Service Life ◽

Structural Capacity ◽

Concrete Layer ◽

Maintenance And Rehabilitation ◽

Highly Correlated ◽

Asset Managers

Road asset managers need to utilize reliable indicators for the structural condition and remaining service life at the network level to make rational decisions of the required funding and the optimum strategies for maintenance and rehabilitation. The surface deflection bowls and pavement critical responses were generated by computer simulations for a total of 2880 flexible pavement sections. The normalized area was computed from the deflection bowl data and it was found to be very well correlated with the compressive strain at the top of the subgrade. While the pavement surface curvature and area under pavement profile were highly correlated with the tensile strain at the bottom of the asphalt concrete layer. Thus, these parameters were used to evaluate the remaining service life in rutting and fatigue. Field data showed an excellent match between the trends obtained from the field and computer simulated data.

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Structural Condition Assessment of Steel-Framed Maintenance Plant in Muara Badak, Balikpapan, East Kalimantan

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.845.344 ◽

2016 ◽

Vol 845 ◽

pp. 344-355

Author(s):

Adinda Chaerany ◽

Ali Awaludin ◽

Henricus Priyosulistyo ◽

Andreas Triwiyono

Keyword(s):

Structural Analysis ◽

Service Life ◽

Structural Model ◽

Structural Condition ◽

Condition Assessment ◽

Assessment Procedure ◽

Load Testing ◽

Remaining Service Life ◽

Structural Condition Assessment ◽

Existing Structure

Structural condition assessment was conducted to a single-story, steel-framed maintenance plant. The assessment procedure aimed to ensure safe and sound operation of the existing structure, to determine its remaining service life as well as to propose the appropriate remedial actions for the existing structure. The assessment was performed through visual observation, Non-Destructive Testing (NDT), field load testing, also by carrying out structural analysis upon verified structural model. Corrosion and buckling are the main types of deterioration found within the structure owing to high salinity and slender steel sections. Structural analysis gave maximum stress ratio of 0.374. Static load testing resulted in deflection value of 17 mm, while dynamic load testing resulted in dynamic amplification factor of 1.06. In conclusion, the existing structure is considered to be structurally safe and sound with remaining service life of approximately 36 years and subjected to structural maintenance and strengthening.

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A Possible Basis for Nondestructive Characterization of Ropes of Nylon 6

MRS Proceedings ◽

10.1557/proc-503-243 ◽

1997 ◽

Vol 503 ◽

Author(s):

H. Jiang ◽

M. K. Davis ◽

R. K. Eby ◽

P. Arsenovic

Keyword(s):

Tensile Strength ◽

Service Life ◽

Fiber Diameter ◽

Structural Parameters ◽

Crystal Form ◽

Nylon 6 ◽

Remaining Service Life ◽

Nondestructive Characterization ◽

Fractional Content

ABSTRACTPhysical properties and structural parameters have been measured for ropes of nylon 6 as a function of the number of use operations. The fractional content of the α crystal form, sound velocity, birefringence, tensile strength and length all increase systematically and significantly with increasing the number of use operations. The fractional content of the γ crystal form and fiber diameter decrease with use. These trends indicate that the measurement of such properties and structural parameters, especially the length, provide a possible basis for establishing a reliable, rapid, and convenient nondestructive characterization method to predict the remaining service life of nylon 6 ropes.

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A new method for correcting temperature log profiles in low-enthalpy plays

Geothermal Energy ◽

10.1186/s40517-020-00181-w ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

Sandra Schumacher ◽

Inga Moeck

Keyword(s):

Input Parameter ◽

New Method ◽

Geothermal Resources ◽

The North ◽

Deep Wells ◽

Thermal Disturbance ◽

Drilling Operations ◽

Crucial Information ◽

Well Data ◽

Drilling Time

Abstract Temperature logs recorded shortly after drilling operations can be the only temperature information from deep wells. However, these measurements are still influenced by the thermal disturbance caused by drilling and therefore do not represent true rock temperatures. The magnitude of the thermal disturbance is dependent on many factors such as drilling time, logging procedure or mud temperature. However, often old well reports lack this crucial information so that conventional corrections on temperature logs cannot be performed. This impedes the re-evaluation of well data for new exploration purposes, e.g. for geothermal resources. This study presents a new method to correct log temperatures in low-enthalpy play types which only requires a knowledge of the final depth of the well as an input parameter. The method was developed and verified using existing well data from an intracratonic sedimentary basin, the eastern part of the North German Basin. It can be transferred to other basins with little or no adjustment.

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Determination of the Vertical Load on the Carrying Structure of a Flat Wagon with the 18–100 and Y25 Bogies

Applied Sciences ◽

10.3390/app11094130 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4130

Author(s):

Oleksij Fomin ◽

Alyona Lovska ◽

Václav Píštěk ◽

Pavel Kučera

Keyword(s):

Mathematical Model ◽

Fatigue Strength ◽

Service Life ◽

Dynamic Characteristics ◽

Dynamic Load ◽

Field Tests ◽

Vertical Load ◽

Mathcad Software ◽

The Mathematical Model

The study deals with determination of the vertical load on the carrying structure of a flat wagon on the 18–100 and Y25 bogies using mathematic modelling. The study was made for an empty wagon passing over a joint irregularity. The authors calculated the carrying structure of a flat wagon with the designed parameters and the actual features recorded during field tests. The mathematical model was solved in MathCad software. The study found that application of the Y25 bogie for a flat wagon with the designed parameters can decrease the dynamic load by 41.1% in comparison to that with the 18–100 bogie. Therefore, application of the Y25 bogie under a flat wagon with the actual parameters allows decreasing the dynamic loading by 41.4% in comparison to that with the 18–100 bogie. The study also looks at the service life of the supporting structure of a flat wagon with the Y25 bogie, which can be more than twice as long as the 18–100 bogie. The research can be of interest for specialists concerned with improvements in the dynamic characteristics and the fatigue strength of freight cars, safe rail operation, freight security, and the results of the research can be used for development of innovative wagon structures.

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Virtual Monitoring of orthotropic steel deck using bridge weigh-in-motion algorithm: Case study

Structural Health Monitoring ◽

10.1177/1475921718764081 ◽

2018 ◽

Vol 18 (2) ◽

pp. 610-620 ◽

Cited By ~ 1

Author(s):

Longwei Zhang ◽

Hua Zhao ◽

Eugene J OBrien ◽

Xudong Shao

Keyword(s):

Field Tests ◽

Life Assessment ◽

Dynamic Strain ◽

Orthotropic Steel Deck ◽

Remaining Service Life ◽

Fatigue Life Assessment ◽

Weigh In Motion ◽

Gross Vehicle Weight ◽

Bridge Weigh In Motion ◽

Steel Deck

This article outlines a Virtual Monitoring approach for fatigue life assessment of orthotropic steel deck bridges. Bridge weigh-in-motion was used to calculate traffic loads which were then used to calculate “virtual” strains. Some of these strains were checked through long-term monitoring of dynamic strain data. Field tests, incorporating calibration with pre-weighed trucks and monitoring the response to regular traffic, were conducted at Fochen Bridge, which has an orthotropic steel deck and is located in Foshan City, China. In the calibration tests, a 45-t 3-axle truck ran repeatedly across Lane 2, the middle lane in a 3-lane carriageway. The results show that using an influence surface to weigh vehicles can improve the accuracy of the weights and, by inference, of remaining service life calculations. The most fatigue-prone position was found to be at the cutout in the diaphragms. Results show that many vehicles are overweight—the maximum gross vehicle weight recorded was 148 t, nearly 3.6 times heavier than the fatigue design truck.

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