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

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

10.33593/2km27z9r ◽

2021 ◽

Author(s):

Pia Mandahus ◽

Lukas Eberhardsteiner ◽

Bernhard Pichler ◽

Mehdi Aminbaghai ◽

Ronald Blab

Keyword(s):

Service Life ◽

Input Parameter ◽

Field Tests ◽

Visual Assessment ◽

Structural Condition ◽

New Method ◽

Concrete Pavements ◽

Linear Measurements ◽

Rigid Pavement ◽

Remaining Service Life

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 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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Modelling of Corrosion-Induced Concrete Cover Cracking Due to Chloride Attacking

Materials ◽

10.3390/ma14061440 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1440

Author(s):

Pei-Yuan Lun ◽

Xiao-Gang Zhang ◽

Ce Jiang ◽

Yi-Fei Ma ◽

Lei Fu

Keyword(s):

Service Life ◽

Corrosion Current ◽

Practical Experience ◽

Concrete Cover ◽

Premature Failure ◽

Rc Structures ◽

Structural Capacity ◽

Cover Cracking ◽

Deterioration Process ◽

Cracking Process

The premature failure of reinforced concrete (RC) structures is significantly affected by chloride-induced corrosion of reinforcing steel. Although researchers have achieved many outstanding results in the structural capacity of RC structures in the past few decades, the topic of service life has gradually attracted researchers’ attention. In this work, based on the stress intensity, two models are developed to predict the threshold expansive pressure, corrosion rate and cover cracking time of the corrosion-induced cracking process for RC structures. Specifically, in the proposed models, both the influence of initial defects and modified corrosion current density are taken into account. The results given by these models are in a good agreement with practical experience and laboratory studies, and the influence of each parameter on cover cracking is analyzed. In addition, considering the uncertainty existing in the deterioration process of RC structures, a methodology based on the third-moment method in regard to the stochastic process is proposed, which is able to evaluate the cracking risk of RC structures quantitatively and predict their service life. This method provides a good means to solve relevant problems and can prolong the service life of concrete infrastructures subjected to corrosion by applying timely inspection and repairs.

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Development of Structural Condition Index to Support Pavement Maintenance and Rehabilitation Decisions at Network Level

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1827-02 ◽

2003 ◽

Vol 1827 (1) ◽

pp. 10-17 ◽

Cited By ~ 10

Author(s):

Zhanmin Zhang ◽

German Claros ◽

Lance Manuel ◽

Ivan Damnjanovic

Keyword(s):

Evaluation Method ◽

Surface Condition ◽

Condition Index ◽

Structural Condition ◽

Pavement Management ◽

Structural Deformation ◽

Pavement Maintenance ◽

State Highway ◽

Structural Reinforcement ◽

Maintenance And Rehabilitation

Every year, state highway agencies apply large amounts of seal coats and thin overlays to pavements to improve the surface condition, but these measures do not successfully address the problem. Overall pavement condition continues to deteriorate because of the structural deformation of pavement layers and the subgrade. To make effective decisions about the type of treatment needed, one should take into consideration the structural condition of a pavement. Several different structural estimators can be calculated by using falling weight deflectometer data and information stored in the Pavement Management Information System (PMIS) at the Texas Department of Transportation. The analysis considers pavement modulus and structural number as the structural estimators of a pavement. The evaluation method is based on the sensitivity of the structural estimators to deterioration descriptors. The deterioration per equivalent single-axle load of all major scores stored in the Texas PMIS is proposed as the primary indicator of pavement deterioration. In addition, the use of the structural condition index is recommended as a screening tool to discriminate between pavements that need structural reinforcement and those that do not. This index is calibrated for use in maintenance and rehabilitation analysis at the network level.

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Vegetation Canopy Coverage Estimation Using Physical Models

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.4709 ◽

2013 ◽

Vol 726-731 ◽

pp. 4709-4713

Author(s):

Lin Jing Zhang ◽

Hong Zhang Ma ◽

Zhu Bo Zhou ◽

Zhong Liang Ren ◽

Xiao Bo Zhu ◽

...

Keyword(s):

Regression Model ◽

Simulated Data ◽

Hyperspectral Data ◽

Physical Models ◽

Vegetation Canopy ◽

Canopy Coverage ◽

Vegetation Indexes ◽

Ground Measurement ◽

Highly Correlated ◽

Coverage Estimation

Based on the physical models of PROSPECT, SAIL and porosity model, hyperspectral data and canopy coverage data of different combined scenes were simulated. According to the simulated data, we chose four sensitive bands and four sensitive vegetation indexes highly correlated to vegetation canopy coverage, and analyzed the correlation between sensitive bands, sensitive vegetation indexes and canopy coverage. Then we built a regression model of canopy coverage with EVI highly correlated with canopy coverage. At last, we verified this model by experimental data from ground measurement experiment. It shows that there is a high correlation between EVI and canopy coverage and the regression model built by EVI can produce an effective result and the RMSE is less than 0.09.

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