Download or read book Investigation of the Modified Lottman Test to Predict the Stripping Performance of Pavements in Colorado written by Timothy Aschenbrener and published by . This book was released on 1993 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of the Iowa Vacuum Tester written by William Outcalt and published by . This book was released on 1998 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluation of joint seals has been a difficult job. The Iowa Department of Transportation has developed a testing system that gives a positive indication where there is a place where a joint seal leaks. This study evaluates the Iowa Vacuum Testing System and compares its results with those obtained by experienced visual evaluators on several types of seals in concrete pavement. Recommendations are made concerning use, maintenance, and possible changes in the system.
Download or read book Transportation Research Record written by and published by . This book was released on 1996 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Asphalt Paving Technology written by Association of Asphalt Paving Technologists and published by . This book was released on 1995 with total page 868 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Long term Performance of Accelerated Rigid Pavements Project CXMP 13 0006 07 written by Ardani Ahmad and published by . This book was released on 1996 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the post-construction evaluation of the fast track pavement in Sterling, Colorado. The field evaluation consisted of visual inspection, fault measurement, profile measurement and distress survey. A set of falling weight deflectometer (FWD) measurements was also acquired to assess the structural responses and to evaluate load transfer efficiency between the slabs. The results of this study demonstrated that fast track concrete can be as durable as the conventional concrete pavement. After seven years of being in service the pavement has shown no sign of fatigue, only some minor distresses unrelated to fast track techniques.
Download or read book Crack reduction Pavement reinforcement Glasgrid written by Donna S. Harmelink and published by . This book was released on 1993 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effectiveness of Antistripping Additives in the Field written by G. W. Maupin and published by . This book was released on 1995 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stripping has long been recognized as a cause of asphalt pavement damage. Water may get between the asphalt film and the aggregate surface, causing an adhesive failure, or water may combine with the asphalt to affect the cohesive strength of the material. Various types of antistripping additives have been used in the attempt to alleviate or eliminate stripping. The Virginia Department of Transportation has used antistripping additives in some of its asphalt mixes since the 1960's. In the 1980's hydrated lime was found to outperform several al chemical additives. VDOT began to require asphalt contractors to use chemical additives that produced test results equal or superior to hydrated lime. Presumably, chemical additives were then improved to compete with hydrated lime. This study was undertaken to find if the new generation of additives prevented stripping in Virginia's hot mix asphalt. Twelve test sections were established, 9 using chemical additives and 3 containing hydrated lime. After 3 to 4 years, eight of the sections containing chemical additive demonstrated considerable visual stripping in cores. The sections containing hydrated lime showed much less stripping. The TSR test used on mix sampled during construction did not accurately predict the stripping that occurred. A follow-up survey of existing pavements should be conducted to verify the possible inadequacy of some chemical additives. Also, the TSR test should be examined and possibly modified to more closely duplicate Virginia's environmental conditions.
Download or read book Loading Test of GRS Bridge Pier and Abutment in Denver Colorado written by Kanop Ketchart and published by . This book was released on 1997 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigating Performance of Geosynthetic reinforced Soil Walls written by Nelson N. S. Chou and published by . This book was released on 1993 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Documentation of Hot Mix Asphalt Overlays on I 25 in 1994 written by Timothy Aschenbrener and published by . This book was released on 1995 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preliminary Environmental Evaluation of Caliber M1000 Deicer for Use in Colorado written by William M. Lewis and published by . This book was released on 2000 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determining the Degree of Aggregate Degradation After Using the NCAT Asphalt Content Tester written by Randolph Reyes and published by . This book was released on 1997 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the research conducted was to determine if aggregate degradation takes place and to measure the possible degree of degradation after bituminous mixtures are heated inside the NCAT Asphalt Content Tester. A study was conducted which compared the original aggregate blend (control specimens) to the residual aggregate blend (experimental specimens) obtained after several bituminous mixtures were heated inside the NCAT Asphalt Content Tester. The control specimens and the experimental specimens used to produce the bituminous mixtures were the result of an aggregate sample which was split three times. Two methods of analysis were used to review the gradation results.
Download or read book Determining Optimum Asphalt Content with the Texas Gyratory Compactor written by Timothy Aschenbrener and published by . This book was released on 1993 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: A recent change from the California kneading compactor to the Texas gyratory compactor has resulted in significantly lower optimum asphalt contents. Additionally, only one laboratory compactive effort has been used in Colorado regardless of traffic or high temperature environment. Adjustments are being made to the Colorado's hot mix asphalt design procedure to address these concerns. It was decided to use results from the recently acquired European equipment to assist with the adjustments. Additionally, results were used from three other sources: (1) the previously used California kneading compactor, (2) samples from older pavements that were recompacted in the Texas gyratory, and (3) experimental field projects that used the recommended end-point stresses. Optimum asphalt contents need to be determined using varying laboratory compactive efforts that correspond to the various traffic and environmental conditions in Colorado. The recommendations presented in this report include the variable end-point stresses for the Texas gyratory to obtain the optimum asphalt content along with the traffic and environmental categories to assist designers on the appropriate selection of the specified end-point stress. Additionally, minimum Hveem stability values, minimum voids in the mineral aggregate, and an acceptable range for voids filled with asphalt are included.
Download or read book Hot Bituminous Pavement QC QA Projects Constructed in 1996 Under QPM 2 Specifications written by Bud A. Brakey and published by . This book was released on 1997 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents Tables and Figures which summarize the HBP Quality Level Analysis (QLA) for projects completed in 1996, the second season using the latest significant revision to the specifications. The quality Level (QL) for the elements (sieve analysis, asphalt content, and pavement density) and the item composites are summarized. While QL determines Pay Factor (PF), it is also used to rank contractors' performance. The item QL improved 1.3 percentage points in 1996 over 1995. But the incentive/disincentive payments were not sufficient to cause some of the contractors to improve their process control. Both, the better and porrer performing contractors show up with similar rankings from year to year. The QLA specifications essentially are serving satisfactorily. Implementation: The PF formulas were modified for the 1997 season so as to make the pF continuous in relation to the QL, rather than in steps as has been the procedure. It is suggested the methods of applying weight factors to the element QL's for PF calculations be reviewed for possible changes. Some other changes in the specification and computer software are needed.
Download or read book Highway Research Abstracts written by and published by . This book was released on 1994 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Evaluation of Various Corrosion Protection Systems of Bridges in Colorado written by Yunping Xi and published by . This book was released on 2004 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion of reinforced concrete structures has been a significant problem for many state and transportation agencies since the application of deicing salts was introduced. Much research has been conducted to develop corrosion protection systems that can prolong the life span of reinforced concrete structures. The Colorado Department of Transportation (CDOT) has several routine and experimental measures to prevent corrosion of the rebar including epoxy-coated rebar, calcium nitrite admixture, organic corrosion inhibitors, a thick cover of quality concrete, and a waterproofing membrane covered by an asphalt overlay. An extensive literature review was performed to collect information on various corrosion protection systems that have been used in the U.S. and around the world. Current CDOT practices in terms of corrosion protection measures were reviewed. A draft inspection plan for Colorado's bridge structures was proposed.
Download or read book Rehabilitation of Rutted Asphalt Pavements written by Ahmad Ardani and published by . This book was released on 1993 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
