Evaluation of bituminous surfaces produced by the turbulent-mass process

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Date Created
1976
Description
The new turbulent-mass process for mixing asphaltic concrete paving mixtures has been under study since its recent introduction in 1970. It is increasing in popularity with contractors because of two reasons: the mixing plant requires less equipment; and the process itself appears to result in a significant reduction in polluting emissions. All of this should reduce the cost of production. Field and laboratory tests and observations indicate that a satisfactory product can be produced by this process, one that is at least equal to conventional plant-mix

Tests on cores drilled from 1 C.C. pavements and concrete bases placed during 1956

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Date Created
1957-03
Description
This investigation is conducted every year for the purpose of securing information as to the compressive strength and thickness of concrete pavements as constructed under present methods, and to ascertain these factors as they pertain to specification requirements. The following data are obtained for each core drilled: project number, station and location with respect to center line at which each core was drilled, date concrete was placed, date drilled, date core was tested, the height, strengths, and diameter of each core. In the summary of results some of the data is omitted and some is indicated in a different form. The date placed is omitted and the age when drilled and the age when tested is used in place of the drilling and testing dates. The height of the core as shown in the report is the height prior to capping. The location from which the core was taken is measured in the field and the data submitted with the cores for use in the report. Side cores were generally taken two feet from the outer edge of the pavement, and the center cores were taken two to six feet from the center line.

Investigation No. 166 Phase II: Resealing joints in Concrete pavements with Preformed Neoprene - Final Report

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Creator
Date Created
1968
Description
This investigation was initiated to determine the practicality of using preformed neoprene in lieu of the presently used hot rubber asphalt for resealing transverse joints in old concrete pavements. The transverse joints on two short sections of pavement in the Twin City area were resealed with neoprene to determine the most effective methods for removing the old seal from the joint, repairing spalls where required, and placing the neoprene joint sealer. On the basis of other studies it was assumed that preformed neoprene would perform better than hot rubber asphalt as a joint sealer. Therefore, the only basis for evaluation in this study is a comparison of the cost of resealing with the new materials. As a result of this cost comparison it is concluded that it is not economically practical to reseal joints in concrete pavements with pre- formed neoprene. Preformed neoprene has been used almost exclusively during the past. two years to seal transverse joints on new concrete pavement, construction. This use of neoprene in new construction is also being studied and it is anticipated that a progress report on its performance will be completed during 1968

Laboratory Evaluation of Tri-Kote Concrete Treatment: Final Report

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Date Created
1967
Description
This study was initiated to evaluate Tri-Kote 18 Crect as a concrete treatment. Tri-Kote is a blend of chlorinated rubber, epoxies, and several other materials, which serves as a treatment for both new and old concrete surfaces. According to the manufacturer (T K Products Inc., Minneapolis, Minnesota), Tri-Kote performs as a membrane curing compound and protective treatment against salt scaling for new concrete and as a protective treatment for old concrete. The study of Tri-Kote as a protective treatment for old concrete was assumed not to be essential since the treatment now used (see MHD Specification 3917) is less expensive than Tri-Kote and is considered quite satisfactory from a performance standpoint. The use of Tri-Kote as a membrane curing compound and protective treatment on new concrete was, however, thought to possibly be more economical than the presently used combination of a polyethylene cure and protective treatment, and was therefore subjected to an evaluation study. Since it was found that Tri-Kote, when applied at a rate somewhat greater than that suggested by the manufacturer, did meet Minnesota Highway Department Specification 3754 for concrete membrane curing compounds, only an evaluation of Tri-Kote as a protective treatment on new concrete was made. This study then consists of a comparison of Tri-Kote treated and non-treated concrete with regards to durability.

The Effect of Polystyrene Molds on Concrete Cylinder Strengths

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Creator
Date Created
1969
Description
This study was initiated to evaluate the effect of foamed polystyrene concrete cylinder molds on concrete strength. The objective of the research was to determine if polystyrene molds: 1) significantly protect concrete cylinders against extremes in temperatures during casting and the initial 24 hour cure period, and 2) eliminate the possible effects of rough handling of specimens which is sometimes encountered in stripping and shipping.

Epoxy Injection for Repair of Bridge Deck Delaminations

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Creator
Date Created
1987-02
Report Number
87-01
Description
A delaminated concrete bridge deck was repaired in 1983 using epoxy injection and conventional concrete patching techniques. Approximately half of the deck was repaired by each method. The deck was monitored for two years to determine the durability of the repairs made by epoxy injection. It appears that these repairs are holding up well. Cost information indicates that the epoxy injection may be a viable alternative to concrete patching where delaminations are present, but the surface deck is sound.

Effect of Tridem-Axle Loading on Concrete Pavement Performance

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Date Created
1983-10
Report Number
83-07
Description
A field program of strain and deflection measurements was conducted. The objective of the program was to evaluate the effect of frozen support, tied-concrete shoulder, and tridem-axle loading on concrete pavement performance. Results of the study on the effect of tridem-axle loading are presented in this paper. Field measurements were obtained during October1982 and February 1983 at five pavement project sites located on 1-90 in the State of Minnesota. Measurements included edge and corner deflections and edge strains. Loadings applied were 20 kip single-axle, a 34 kip tandem-axle, a 42 kip tandem-axle, and a 42 kip tridem-axle. Theoretical analysis was also conducted using a finite element program. Study results also indicate that for application to the AASHTO thickness design procedure, a tridem-axle can be considered as equivalent to a single-axle weighing about 50 percent of the tridem-axle and to a tandem-axle weighing about 80 percent of the tridem-axle. Traffic equivalence factors are presented for tridem-axles on concrete pavements.

Effect of Frozen Support on Concrete Pavement Performance

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Date Created
1983-10
Report Number
83-06
Description
A field program of strain and deflection measurements was conducted. The objective of the program was to evaluate the effect of frozen support, tied-concrete shoulder, and tridem-axle loading on concrete pavement performance. Results of the study on the effect of frozen support are presented in this paper. Field measurements were obtained during October.1982 and February 1983 at five pavement project, sites located on 1-90 in the State of Minnesota. Measurements included edge and corner deflections and edge strains. Loadings applied were 20 kip single-axle, a 34 kip tandem-axle, a 42 kip tandem-axle, and a 42 kip tridem-axle. Theoretical analysis was also conducted using a finite element program. Study results indicate that pavement deflections and strains are greatly reduced during winter months when the support 1s frozen. Based on analysis of these results, it is concluded that the effect of axle loads applied during the winter can be considered to be only 1/7th as damaging as the same loads applied during fall month

Continuously Reinforced Concrete Pavement Inventory

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Date Created
1982-11
Report Number
82-05
Description
A typical concrete pavement has expansion and contraction joints across and along the pavement surface. The joints allow the pavement to change in dimension with changes in temperature. A continuously reinforced concrete pavement (CRCP) does not have expansion or contraction joints. Random, closely spaced cracks are expected to develop naturally and allow for expansion and contraction due to temperature changes. The many random cracks eliminate expensive joint maintenance. This maintenance-free service life feature has not occurred in Minnesota. During past years, an increasing number of CRCP s have exhibited deterioration where pieces of concrete separate from the surface of the pavement and potholes result. This is termed spalling. The frequency and extent of this deterioration has progressed from isolated and random to widespread and frequent. A comprehensive program was initiated by Mn/DOT to study this problem and develop possible solutions. This CRCP inventory is a physical evaluation of the extent of corrosion on random, sections of pavement. It is related to concurrent efforts which will evaluate CRCP rehabilitation, techniques.