Effects of Base Support and Load Transfer Efficiency (LTE) on Portland Concrete Pavement Performance

2010 ◽  
Vol 38 (1) ◽  
pp. 102010 ◽  
Author(s):  
M. R. Mitchell ◽  
R. E. Link ◽  
Dar-Hao Chen ◽  
Huang-Hsiung Lin
2016 ◽  
Vol 9 (2) ◽  
pp. 263-274
Author(s):  
L. S. Salles ◽  
J. T. Balbo

ABSTRACT Four continuously reinforced concrete pavement (CRCP) sections were built at the University of São Paulo campus in order to analyze the pavement performance in a tropical environment. The sections short length coupled with particular project aspects made the experimental CRCP cracking be different from the traditional CRCP one. After three years of construction, a series of nondestructive testing were performed - Falling Weight Deflectometer (FWD) loadings - to verify and to parameterize the pavement structural condition based on two main properties: the elasticity modulus of concrete (E) and the modulus of subgrade reaction (k). These properties estimation was obtained through the matching process between real and EverFE simulated basins with the load at the slab center, between two consecutive cracks. The backcalculation results show that the lack of anchorage at the sections end decreases the E and k values and that the longitudinal reinforcement percentage provides additional stiffness to the pavement. Additionally, FWD loadings tangential to the cracks allowed the load transfer efficiency (LTE) estimation determination across cracks. The LTE resulted in values above 90 % for all cracks.


Teknik Dergi ◽  
2021 ◽  
Author(s):  
Muhammet ÇELİK ◽  
Mehmet Tevfik SEFEROĞLU ◽  
Muhammet Vefa AKPINAR ◽  
Mohammad Manzoor NASERY ◽  
Ayşegül Güneş SEFEROĞLU

Author(s):  
Mustaque Hossain ◽  
John B. Wojakowski

Six jointed reinforced concrete pavement and one jointed plain concrete pavement test sections on US-69 in Miami County, Kansas, constructed in 1979 have been surveyed annually for faulting for the past 9 years. Falling weight deflectometer tests were conducted in 1995 to assess the load transfer efficiency of the joints. The results show that, in general, as the original concrete density increases due to improved consolidation, the rate of increase of the joint fault depth decreases at doweled joints at a given pavement age. The occurrence of joint faulting is much more severe when load transfer devices are not present; this was observed even for the pavement section built on a nonerodible subbase. Improved consolidation sometimes appeared to help improve load transfer, resulting in a lower rate of faulting. Thus, the mandatory density requirement of 98 percent rodded unit weight, which has been in effect since 1980, has undoubtedly led to better joint performance for concrete pavements in Kansas.


2015 ◽  
Vol 42 (11) ◽  
pp. 845-853 ◽  
Author(s):  
Piotr Mackiewicz

The suitable load transfer between adjacent concrete slabs in transverse joint is influenced by various parameters. In this paper, the influence of different diameters and spacing of dowel bars on the slab interaction was considered. Calculations were carried out with application of 3D finite element method. Verification of the model was performed with the concrete pavement in Poland. Results of these calculations were compared with falling weight deflectometer studies. Calculations of stress concentration around dowel bars for different conditions and parameters enabled to determine a relationship between load transfer efficiency (LTE) and vertical compressive stresses in the concrete slab. It was found that application of dowels with small diameters can promote damages in the concrete slab because of concentration of vertical compressive stresses under the dowel bar. The found relationship enables to determine stresses in concrete under the dowel according to its diameter and LTE.


Author(s):  
Neeraj Buch ◽  
Dan G. Zollinger

The results of an in-depth study of factors that affect dowel looseness in jointed concrete pavements are presented. The laboratory investigation revealed the influence of aggregate type (in relation to oxide content), aggregate texture and shape, bearing stress (dowel diameter and crack width), load magnitude, and number of load cycles on the magnitude of dowel looseness and the subsequent loss in load transfer efficiency across saw-cut joints. A discussion is included on the development of an empirical-mechanistic dowel looseness prediction model based on the experimental results. Results of the sensitivity analysis of the dowel looseness prediction model (using laboratory data) are also presented. An associated scope of this research was to develop a relationship between dowel looseness and loss of load transfer efficiency. The sequential use of the dowel looseness prediction model and its relationship to load transfer efficiency allows the design engineer to predict load transfer characteristics of a joint, based on calculated (or measured) dowel looseness. The framework suggested to predict dowel looseness can then be incorporated into a fault prediction model for doweled joints.


2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
Xiaolan Liu ◽  
Xianmin Zhang ◽  
Yadong Wang

The evaluation method of load transfer efficiency using falling weight deflectometer is unworkable in remote mountain areas and transportation difficult region. Therefore, a novation method of load transfer efficiency evaluation is proposed using the index of amplitude ratio. Finite element method is applied to study the influence of dowel bar parameters (diameter, length, spacing, and elastic modulus) and pavement structures parameters (thickness and modulus) on load transfer efficiency, frequency, and the ratio of amplitude. Results of finite element model show that the effects of dowel bar and pavement structure parameters on load transfer efficiency and the ratio of amplitude are similar. The load transfer efficiency, frequency, and the ratio of amplitude enhance with the increase of dowel bar diameter, length, and elastic modulus and the decrease of dowel bar spacing. The subgrade modulus has more significant influence on the load transfer efficiency, frequency, and the ratio of amplitude than other pavement parameters. Polynomial function method is utilized to established load transfer mode between deflection-based load transfer efficiency and the ratio of amplitude. The feasibility and reliability of new method is verified by static and dynamic load test. All results are helpful for the development of highway engineering and airport engineering.


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