Cracking and Seating to Retard Reflective Cracking PDF Download

Author: Gary K. Harris
Publisher:
ISBN:
Category : Pavements, Asphalt concrete
Languages : en
Pages : 33

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Author: Gary Shrum
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 12

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Book Description
To evaluate the effect of various sizes of cracking and seating of pcc pavement prior to resurfacing on reflective cracking and structural rating.

Author: Gary K. Harris
Publisher:
ISBN:
Category : Pavements, Asphalt concrete
Languages : en
Pages : 22

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Book Description

Author: Larry M. Stark
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 21

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Book Description
To evaluate the effectiveness of various cracking sizes and patterns with different thicknesses of asphalt overlays.

Author: Amy M. Schutzbach
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 112

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Book Description

Author: R. Christopher Williams
Publisher:
ISBN:
Category : Pavements, Asphalt
Languages : en
Pages : 142

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Book Description
Reflective cracks form in pavements when hot-mix asphalt (HMA) overlays are placed over jointed and/or severely cracked rigid and flexible pavements. In the first part of the research, survival analysis was conducted to identify the most appropriate rehabilitation method for composite pavements and to evaluate the influence of different factors on reflective crack development. Four rehabilitation methods, including mill and fill, overlay, heater scarification (SCR), and rubblization, were analyzed using three performance indicators: reflective cracking, international roughness index (IRI), and pavement condition index (PCI). It was found that rubblization can significantly retard reflective cracking development compared to the other three methods. No significant difference for PCI was seen among the four rehabilitation methods. Heater scarification showed the lowest survival probability for both reflective cracking and IRI, while an overlay resulted in the poorest overall pavement condition based on PCI. In addition, traffic level was found not to be a significant factor for reflective cracking development. An increase in overlay thickness can significantly delay the propagation of reflective cracking for all four treatments. Soil types in rubblization pavement sites were assessed, and no close relationship was found between rubblized pavement performance and subgrade soil condition. In the second part of the research, the study objective was to evaluate the modulus and performance of four reflective cracking treatments: full rubblization, modified rubblization, crack and seat, and rock interlayer. A total of 16 pavement sites were tested by the surface wave method (SWM), and in the first four sites both falling weight deflectometer (FWD) and SWM were conducted for a preliminary analysis. The SWM gave close concrete layer moduli compared to the FWD moduli on a conventional composite pavement. However, the SWM provided higher moduli for the rubblized concrete layer. After the preliminary analysis, another 12 pavement sites were tested by the SWM. The results showed that the crack and seat method provided the highest moduli, followed by the modified rubblization method. The full rubblization and the rock interlayer methods gave similar, but lower, moduli. Pavement performance surveys were also conducted during the field study. In general, none of the pavement sites had rutting problems. The conventional composite pavement site had the largest amount of reflective cracking. A moderate amount of reflective cracking was observed for the two pavement sites with full rubblization. Pavements with the rock interlayer and modified rubblization treatments had much less reflective cracking. It is recommended that use of the modified rubblization and rock interlayer treatments for reflective cracking mitigation are best.

Author: Marshall R. Thompson
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 52

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Book Description
This synthesis will be of interest to pavement designers, maintenance engineers, and others interested in reducing reflection cracking of asphalt overlays on portland cement concrete (PCC) pavement. Information is presented on the technique of breaking or cracking of the concrete pavement into small segments before overlaying with asphalt concrete. Asphalt concrete overlays on existing PCC pavements are subject to reflection cracking induced by thermal movements of PCC pavement. This report of the Transportation Research Board discusses the technique of breaking/cracking and seating of the existing PCC before an overlay as a means to reduce or eliminate reflection cracking.

Author: Ashraf M. Rahim
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 112

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Book Description
Performance data for these sections were obtained from the Caltrans Pavement Condition Report (PCR) and were analyzed along with inventory data obtained from as-built sheets. In Phase II, seventeen (17) CS&O sections (eight (8) on the Central Coast and nine (9) in Northern California) were identified and examined. Performance data were extracted from the Caltrans PCR. As-built and maintenance history data were obtained from the Caltrans District 05 (D05) and District 02 (D02) offices. Data for these sections were combined with data from the Central Valley region (Phase I) to evaluate the performance of CS&O sections throughout California. Also, performance models were developed for three different regions, namely Central Valley (CV), Central Coast (CC), and Northern California (NCA).

Author: Thomas Elliott Freeman
Publisher:
ISBN:
Category : Concrete slabs
Languages : en
Pages : 15

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Book Description
This report presents the results of an evaluation of concrete slab fracturing techniques as a means of arresting or retarding reflective cracking through asphalt overlays placed on severely distressed portland cement concrete pavement. The study involved monitoring the performance of five pavement rehabilitation projects over a period of up to 8 years. Two of the projects were originally constructed of jointed plain (unreinforced) concrete, and the other three consisted of jointed reinforced concrete pavement. The test sections were fractured with a guillotine drop hammer and then seated with a 50-ton pneumatic tire roller. For comparative purposes, control sections, which were not fractured prior to placement of the asphalt overlay, were constructed just beyond the bounds of three of the fractured test sections. Detailed visual condition surveys were conducted annually at all sites. For each survey, the number of occurrences of reflective cracks that formed in fractured sections was directly compared to the number of cracks observed in the control sections to quantify the tendency of fracturing to retard or arrest the formation of reflective cracks. The results of this study show that fracturing and seating distressed concrete pavements appear to be an effective means of retarding the formation of reflective cracking through asphalt overlays on jointed, unreinforced pavements. In the case of reinforced pavements, however, the fracturing technique was somewhat less successful in that the formation of reflective cracks appeared to be delayed for only about 3 years. Beyond that point in time, the fractured reinforced sections exhibited approximately the same amount of reflective cracking as the control section. The researcher concludes that any observed benefit in terms of extended pavement service life or enhanced ride quality resulting from even a slight delay in reflective crack propagation would likely offset the rather nominal cost of the fracturing and seating operation itself.

Author:
Publisher:
ISBN:
Category : Highway research
Languages : en
Pages : 464

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Book Description