Laboratory Evaluation of GeoGauge for Compaction Control

2003 ◽  
Vol 1849 (1) ◽  
pp. 20-30 ◽  
Author(s):  
Lary R. Lenke ◽  
R. Gordon McKeen ◽  
Matt P. Grush
Keyword(s):  
Density Measurement ◽  
Laboratory Evaluation ◽  
Property A ◽  
Soil Stiffness ◽  
Boundary Constraints ◽  
Safety Issues ◽  
State Highway ◽  
Field Compaction ◽  
Compaction Control ◽  
State Highway Agencies

The use of nuclear methods for compaction control is increasingly problematic for state highway agencies. Regulatory and safety issues have prompted agencies such as the New Mexico State Highway and Transportation Department to look for nonnuclear alternatives for compaction control. A laboratory evaluation of one such commercially available device, known as the GeoGauge, is described. The GeoGauge measures soil stiffness, arguably a more viable engineering parameter than moisture—density measurement. The GeoGauge was found to measure soil stiffness as advertised. Results relating moisture, density, and stiffness were found to be consistent with earlier research on compaction and mechanical strength of soils. However, because of the dynamic nature of the measurement obtained with the GeoGauge and associated boundary constraints, the ability to obtain a target value for stiffness in the laboratory has proved to be elusive. Because of the promising nature of the GeoGauge technology, and because it measures a true engineering mechanical property, a paradigm shift may be necessary for its implementation in field compaction control. Future specifications for compaction using this technology may require specific controls of moisture and compaction equipment with stiffness monitoring via the GeoGauge.

Using Artificial Intelligence to Estimate Nonlinear Resilient Modulus Parameters from Common Index Properties

2021 ◽  
pp. 036119812110237
Author(s):  
Laura Camarena
Keyword(s):  
Machine Learning ◽  
Material Properties ◽  
Resilient Modulus ◽  
Nonlinear Behavior ◽  
Machine Learning Techniques ◽  
Design Parameters ◽  
Nonlinear Parameters ◽  
State Highway ◽  
Learning Techniques ◽  
State Highway Agencies

The Mechanistic–Empirical Pavement Design Guide (MEPDG) considers a hierarchical approach to determine the input values necessary for most design parameters. Level 1 requires site-specific measurement of the material properties from laboratory testing, whereas other levels make use of equations developed from regression models to estimate the material properties. Resilient modulus is a mechanical property that characterizes the unbound and subgrade materials under loading that is essential for the mechanistic design of pavements. The MEPDG resilient modulus model makes use of a three-parameter constitutive model to characterize the nonlinear behavior of the geomaterials. As the resilient modulus tests are complex, expensive, and require lengthy preparation time, most state highway agencies are unlikely to implement them as routine daily applications. Therefore, it is imperative to make use of models to calculate these nonlinear parameters. Existing models to determine these parameters are frequently based on linear regression. With the development of machine learning techniques, it is feasible to develop simpler equations that can be used to estimate the nonlinear parameters more accurately. This study makes use of the Long-Term Pavement Performance database and machine learning techniques to improve the equations utilized to determine the nonlinear parameters crucial to estimate the resilient modulus of unbound base and subgrade materials.

Determining Minimum Contract Time for Highway Projects

2000 ◽  
Vol 1712 (1) ◽  
pp. 196-201 ◽  
Author(s):  
Jin-Fang Shr ◽  
Benjamin P. Thompson ◽  
Jeffrey S. Russell ◽  
Bin Ran ◽  
H. Ping Tserng
Keyword(s):  
Low Cost ◽  
Road User ◽  
User Cost ◽  
Time Curve ◽  
Highway Projects ◽  
The Road ◽  
State Highway ◽  
Florida Department ◽  
The Cost ◽  
State Highway Agencies

An increasing number of state highway agencies (SHAs) are using A (cost) + B (time cost) bidding ( A + B bidding) for highway construction. The A + B bidding concept is designed to shorten the total contract time by allowing each contractor to bid the number of days in which the work can be accomplished, in addition to the traditional cost bid. The SHA is then presented with the problem of determining a reasonable range of contract time submitted by the bidders. Most SHAs do not currently restrict the range of B. However, several problems may arise from an unrestricted range of B. First, if no minimum is set for B, a bidder may inflate the cost bid and submit an unreasonably low B, using the excess cost bid to cover the disincentives charged for exceeding the time bid. Second, if no maximum is set for B, then a bidder with a high B and a low-cost bid may be awarded the job and make an unreasonable amount of money from incentive payments. This study develops a quantified model of the price-time bidding contract. A construction cost-versus-time curve is developed from Florida Department of Transportation (DOT) data. The contractor’s price-versus-time curve is then combined with the road-user cost to determine the optimum lower limit to be set on B. Finally, several projects completed by the Florida DOT will be used to illustrate this model.

Pay Factor Analysis for Highway Pavements through Percentage of Material within Specification Limits and Monte Carlo Simulation

2021 ◽  
pp. 036119812110255
Author(s):  
Yunpeng Zhao ◽  
Dimitrios Goulias
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Operating Characteristic ◽  
Production Quality ◽  
Specification Limits ◽  
State Highway ◽  
Long Run ◽  
Similar Materials ◽  
Pay Factor ◽  
State Highway Agencies

Many state highway agencies (SHAs) have adopted pay adjustment provisions in their acceptance plans for construction and materials. In these payment adjustment acceptance plans, the percentage of material within specification limits (PWL) has been selected as the quality measure to relate production quality to pay factors, and pay equations are used to determine a pay factor for a lot based on PWL. Various pay equations have been proposed by the highway community for adoption in SHAs’ specifications. However, the effectiveness of these pay equations has not been fully evaluated. Another issue concerning the pay adjustment acceptance plans is the risk associated with single and multiple pay factors. The purpose of this study was to evaluate the effects of different pay equations commonly used by SHAs and the risks associated with pay adjustment acceptance plans. This was achieved by developing operating characteristic curves associated with various pay factors and expected pay curves and Monte Carlo simulation for assessing the effects in the long run. The methodology suggested in this paper is transferable elsewhere where similar materials and specifications are used for the acceptance of pavements.

scholarly journals Multibody model of fruit harvesting trucks: comparison with experimental data and rollover analysis

2018 ◽  
Vol 49 (2) ◽  
pp. 92-99 ◽  
Author(s):  
Stefano Melzi ◽  
Edoardo Sabbioni ◽  
Michele Vignati ◽  
Maurizio Cutini ◽  
Massimo Brambilla ◽  
...  
Keyword(s):  
Experimental Tests ◽  
Soil Stiffness ◽  
Safety Issues ◽  
Multibody Model ◽  
Centre Of Gravity ◽  
Rollover Risk ◽  
Speed Up ◽  
The Stability ◽  
Italian National Institute ◽  
Comparison With Experimental Data

Fruit harvesting trucks are used to easy and speed-up the work of agricultural operators. These vehicles are provided with a moving cargo bed, which can be raised up to 3 meters from the ground so that workers are closer to the plants top. Due to factors like height of centre of gravity and operation on soft and irregular soil, these vehicles present several safety issues. This research, carried out inside a project funded by INAIL (Italian National Institute for Insurance against Accidents at Work), analysed the stability of fruit harvesting trucks with particular focus on rollover risk. Experimental tests were carried out to characterise the response of these vehicles. Multibody models of two trucks were then developed and used to determine the rollover angle along a generic direction considering the effect of vehicle configuration and of tire-soil stiffness.

Integrating Visualization into Structured Public Involvement: Case Study of Highway Improvement in Central Kentucky

2002 ◽  
Vol 1817 (1) ◽  
pp. 50-57 ◽  
Author(s):  
Keiron Bailey ◽  
Joel Brumm ◽  
Ted Grossardt
Keyword(s):  
User Satisfaction ◽  
Public Involvement ◽  
Systems Approach ◽  
Three Dimensional ◽  
Factors Affecting ◽  
State Highway ◽  
Advanced Technologies ◽  
Design Options ◽  
State Highway Agencies

Public involvement in transportation infrastructure decision making is frequently mandated and is regarded as increasingly essential by a wide variety of stakeholders. The integration of advanced technologies, such as visualization, into this process is increasingly desired. However, public involvement processes often are regarded as problematic by many stakeholders and the state highway agencies charged with implementing them. Structured public involvement (SPI) is posited. SPI takes a systems approach toward the integration of advanced technologies into public involvement forums. Because the goal of public involvement is to increase user satisfaction with both the process and the outcomes, the characteristics of advanced technologies and their capacities for gathering useful feedback in public forums must be evaluated. Visualization is put forth as an enabling technology within an SPI framework. The properties, capacities, and transportation-related uses of three visualization modes are evaluated, and their operational features are discussed. A case study dealing with highway improvement in central Kentucky reveals that three-dimensional renderings are significantly preferred to twodimensional and virtual reality modes; the case study also shows that visualization should complement, not replace, other performance information. The role of electronic scoring as an integral component of this SPI protocol is emphasized, resulting in fast assessment and free expression of views. Factors affecting the efficiency of visualization are analyzed, and recommendations are presented for implementing SPI protocols that rely on visualization. These include investigating participants' previous experience with visualization, incorporating iterative public involvement in finalizing design options, and ensuring that the technologies are compatible with the chosen public involvement process.

Laboratory evaluation of electromagnetic density gauges for hot-mix asphalt mixture density measurement

2018 ◽  
Vol 158 ◽  
pp. 1055-1064 ◽  
Author(s):  
Zhen Leng ◽  
Zeyu Zhang ◽  
Yuan Zhang ◽  
Yangyang Wang ◽  
Huayang Yu ◽  
...  
Keyword(s):  
Hot Mix Asphalt ◽  
Asphalt Mixture ◽  
Density Measurement ◽  
Laboratory Evaluation ◽  
Mixture Density

An evaluation of warranty contracting in the United States of America

2006 ◽  
Vol 33 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Mehmet Emre Bayraktar ◽  
Qingbin Cui ◽  
Makarand Hastak ◽  
Issam Minkarah
Keyword(s):  
United States ◽  
United States Of America ◽  
The United States ◽  
Department Of Transportation ◽  
Construction Costs ◽  
Advantages And Disadvantages ◽  
Contract Administration ◽  
State Highway ◽  
Early Failures ◽  
State Highway Agencies

It is believed that warranty contracting would benefit state highway agencies by improving quality, saving money and time, and encouraging contractors' innovations. However, the challenges associated with warranties could be substantial, including higher costs, early failures, a reduction or even elimination of small contractors from the bidding process, and an increase in contract disputes and litigation. The actual impact of warranty provisions on state Department of Transportation (DOT) projects in the United States of America is still unclear because of limited industry experience. This paper provides a detailed discussion of warranty provisions and the benefits and problems associated with the subject matter. The advantages and disadvantages of warranty provisions are evaluated from the conflicting perspectives of state Departments of Transportation (DOTs), contractors, and surety companies. The future prospects of warranty provisions are established based on the findings of a recent study of warranty provisions and existing literature. Also, several options are proposed that have a strong potential to improve the application of warranties on DOT projects.Key words: warranties, highway construction, innovation, highway maintenance, contract administration, construction costs, construction inspection.

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