The Great Unsealing: A Perspective on Portland Cement Concrete Joint Sealing

1997 ◽  
Vol 1597 (1) ◽  
pp. 22-33 ◽  
Author(s):  
Stephen F. Shober
Keyword(s):  
Portland Cement ◽  
National Level ◽  
Cost Effective ◽  
Transportation System ◽  
Pavement Performance ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Wisconsin Department ◽  
Crack Sealing ◽  
Contraction Joints

The general mission of most transportation agencies is to ensure a customer focus in the development and operation of a safe and efficient transportation system. The customers desire comfort, convenience, safety, and cost-effectiveness in a transportation system. Agency research must have the objectives of addressing customer-related issues and measuring benefits of importance to them. Accordingly, any joint and sealant research must answer the questions, Why do we seal? and Is it cost-effective? Joint and sealant studies of portland cement concrete (PCC) pavements must address whether joint sealing enhances total pavement performance and is cost-effective, and, if so, what sealant system should be used. The Wisconsin Department of Transportation (WisDOT) has been studying the effect of PCC joint/crack sealing on total pavement performance for 50 years. By 1967 there was substantial documentation that filling and refilling of contraction joints had no beneficial effect on pavement performance. By 1984, it was concluded that pavements with unsealed joints had better overall performance (distress, ride, materials integrity) than pavements with sealed joints. In 1990, WisDOT passed a policy eliminating all PCC joint sealing, in new construction and maintenance. This "no-seal" policy has saved Wisconsin $6,000,000 annually with no loss in pavement performance and with increased customer safety and convenience. The entire PCC sealing issue is beginning to be addressed at the national level, ensuring no false assumptions and with the customer’s needs in view.

Thermogravimetric Analysis of Limestone Aggregates for Portland Cement Concrete

1998 ◽  
Vol 1619 (1) ◽  
pp. 37-44
Author(s):  
Stephen A. Cross ◽  
Mohamed Nagib Abou-Zeid
Keyword(s):  
Weight Loss ◽  
Thermogravimetric Analysis ◽  
Portland Cement ◽  
Coarse Aggregate ◽  
Pavement Performance ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
The Past ◽  
Good Potential ◽  
Durability Assessment

Durability of coarse aggregate has a major impact on the durability of portland cement concrete. Over the past years, there has been an increasing interest in developing and improving test techniques that provide a more accurate durability assessment, which ultimately leads to a better prediction of pavement performance. Thermogravimetric analysis is a relatively rapid technique that has shown good potential for use in the analysis of carbonate aggregates. Thermogravimetric technique (TG) was used to analyze 31 limestone aggregates. The specimens were heated to temperatures above 1000°C using two rates of temperature increase. The weight loss and the change in weight loss as a function of temperature were recorded. Results show a correlation between the slope before calcite transition and some durability aspects of limestone. Moreover, the TG output can be used to calculate the percent acid insoluble (AI) and the pavement vulnerability factor (PVF). Therefore, TG may be considered as a rapid method for AI and PVF determination.

Assessment of Distress in Conventional Hot-Mix Asphalt and Asphalt–Rubber Overlays on Portland Cement Concrete Pavements

2005 ◽  
Vol 1929 (1) ◽  
pp. 20-27
Author(s):  
Maria Carolina Rodezno ◽  
Kamil E. Kaloush ◽  
George B. Way
Keyword(s):  
Portland Cement ◽  
Large Scale ◽  
Hot Mix Asphalt ◽  
Field Performance ◽  
Fatigue Cracking ◽  
Pavement Performance ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Asphalt Rubber ◽  
Design Guide

The purpose of this study is to assess the way distresses are predicted by using the new Mechanistic–Empirical Design of New and Rehabilitated Pavement Structures (design guide), developed under NCHRP Project 1–37A. Two pavement sections were used: a conventional hot-mix asphalt reconstruction and an asphalt–rubber overlay on a portland cement concrete (PCC) pavement. The design guide does not include rehabilitation design for asphalt–rubber overlays. However, many large-scale asphalt–rubber overlays on interstate highways in Arizona have been built and monitored for performance, providing an opportunity to determine to what degree the design guide can predict their performance. The input data for both types of pavements were derived from two different projects on the same highway, Interstate 40. The actual data measurements that summarize the pavement performance were compared with calculated values obtained by using the design guide. Three pavement performance parameters were evaluated on the basis of the available data: rutting, cracking, and international roughness index (IRI). Rutting was one of the distresses that the design guide predicted more accurately. The fatigue cracking prediction, evaluated with Level-3 data input, was not accurate; future analysis should consider calibrated fatigue models for the different mixtures. The predicted IRI results differed from the actual measured field performance because of inaccurate distress prediction. The Arizona experience using asphalt–rubber overlays to rehabilitate aged PCC pavements has been successful. For that reason, a calibration process that allows the use of the asphalt–rubber mixtures in the design guide should be considered in the future.

Design of a Randomized Tining Rake for Portland Cement Concrete Pavements Using Spectral Analysis

2000 ◽  
Vol 1702 (1) ◽  
pp. 63-68 ◽  
Author(s):  
Ziad S. Saad ◽  
John R. Jaeckel ◽  
Yosef Z. Becker ◽  
David A. Kuemmel ◽  
Alex Satanovsky ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Portland Cement ◽  
Acoustic Noise ◽  
The United States ◽  
Design Stage ◽  
Random Pattern ◽  
Concrete Pavements ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Wisconsin Department

Uniformly spaced, transverse-tined portland cement concrete (PCC) pavements have been in extensive use in the United States since the early 1970s. However, driving on tined pavements generates an uncomfortable acoustic “whine”that has a discrete frequency. Recent research by the Wisconsin Department of Transportation (WisDOT) and FHWA led to an interim guideline for randomization of the tining pattern. The guideline called for tine spacing varying from 10 to 40 mm, with 50 percent of the spacing below 25 mm. At least five states have experimented with this random pattern, with limited success in eliminating the whine. A study was completed recently as part of a WisDOT contract with Marquette University and the HNTB Corporation, and funded by FHWA, to analyze all of the pavements. The tonal properties of acoustical noise were related to the serial arrangement of the tining, showing that the frequencies can be predicted from the power spectrum of the series of tines. A method of designing the series of tines that minimizes and possibly eliminates the presence of these whines is proposed and explained. By predicting the tonal properties of acoustical noise at the rake-design stage, the construction effort in building and researching noise and texture characteristics is substantially reduced. A random rake, designed using the proposed methodology, has been used in tining a road section, and preliminary spectral analysis of the acoustic noise revealed no tining-related discrete tones.

Development of a Capacitor Probe to Detect Subsurface Deterioration in Concrete

1997 ◽  
Vol 503 ◽  
Author(s):  
B. K. Diefenderfer ◽  
I. L. Al-Qadi ◽  
J. J. Yoho ◽  
S. M. Riad ◽  
A. Loulizi
Keyword(s):  
Dielectric Constant ◽  
Portland Cement ◽  
Electromagnetic Waves ◽  
Low Cost ◽  
Complex Dielectric Constant ◽  
Life Cycle Costs ◽  
Parallel Plates ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Set Up

ABSTRACTPortland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. By developing techniques that would enable civil engineers to evaluate PCC structures and detect deterioration at early stages (without causing further damage), optimization of life-cycle costs of the constructed facility and minimization of disturbance to the facility users can be achieved.Nondestructive evaluation (NDE) methods are potentially one of the most useful techniques ever developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part, termed the “loss factor,” describes the conductivity of PCC and the attenuation of electromagnetic waves.Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1 to 40.1MIHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation. A new capacitor probe has been developed which consists of two plates, located within the same horizontal plane, for placement upon the specimen to be tested. Preliminary results show that this technique is feasible and results are promising; further testing and evaluation is currently underway.

Sign in / Sign up

Export Citation Format

Share Document