Minnesota Department of Highways

A limited supply of high quality base aggregates in several parts of Minnesota has resulted in a search for a means of improving the physical and strength characteristics of locally available soils and poor quality granular materials. Other states faced with a similar problem have attempted to use soil stabilization as a solution. Common stabilization agents include cement, bituminous materials, sodium and calcium chloride, and sulfite liquor. More recently, several southern states have successfully used lime for stabilization of roadbed materials. The purpose of this study is to determine the effect of hydrated lime on the physical and strength properties of typical Minnesota soils and aggregates. This first progress report presents the findings of tests conducted during 1961 using hydrated lime and five secondary chemical additives with five fine grained soils

This investigation was included in the research program of the Minnesota Local Road Research Board as a project of special interest to County and Municipal Engineers as well as to Engineers of the Minnesota Highway Department. The project was conducted as a part of the Highway Planning Research Program financed jointly with Federal-Aid funds provided through the United States Department of Commerce, Bureau of Public Roads together with State funds and County and Municipal State-Aid funds. A laboratory study such as this generally does not provide all the information necessary to determine whether a particular method will prove satisfactory as a construction procedure or to accurately predict field performance. This laboratory study does show that lime has some possibilities as an effective treatment for certain Minnesota soils. However, an experimental field project is needed to establish the suitability of the various laboratory tests as a means for evaluating the adequacy of the soil-lime mixtures for use in road structures.

The thermoplastic pavement marking project, S.P. 2785-101 (T.H. 494), was let in 1963 as an experimental project under the Federal-aid highway program, with full Federal-aid participation in the cost of the work. This report covers application of the marking materials under this project and observations on performance during the first three months service.

This report contains the results of experiments performed to discover the suitability of the concrete retarder Plasitment for Minnesota Department of Highways construction projects.

The attached report is a summary and brief analysis of Benkelman Beam tests made during 1967 on various trunk highway sections. The analysis includes estimated allowable spring axle load capacities and general observations on test results and soil conditions. Attention is called to the statements in the report regarding interpretation of the data. The precautionary remarks are very pertinent and must be considered in the application of the test results. This data is not considered criteria for design.

Engineers who are associated with trenching in public thoroughfares have been striving for many years to find better construction methods and procedures for backfilling these trenches. We cannot expect the public to tolerate detrimental settlement if it can be avoided with a reasonable expenditure of funds. In this study the presently used procedures of backfilling and compaction were observed. It was found that these procedures can definitely be improved. The major conclusions which can be drawn from the study are listed below. The layered system is the most reliable compaction procedure for limiting settlement to a minimum. With one compactor type, the Hydra-Hammer, the entire trench backfill can be compacted in one lift irrespective of soil type or traffic volume on the street. Adequate stability, to prevent detrimental settlement, can be attained with many compactor types if the lift height is adjusted to soil type and condition, and the trench loading conditions. All vibratory type trench compactors should be used strictly on the granular soils and the lift height must be chosen with respect to the particular compactor and the traffic volume. The Pneumatic Button Head compactor can effectively compact all soil types in lifts up to 0.5 feet in thickness. The Plate Tampers are excellent compactors for all soil types and they are capable of compacting soil lifts between 1.0 and 1.5 feet depending upon the traffic load. Heavy construction equipment should be used to compact only the upper lift in a trench and this lift should be restricted to the range of 1.0 to 2.5 feet in thickness depending upon the soil type and the traffic load. Further research under more controlled field conditions is planned for 1963.

This study was undertaken to determine the comparative effectiveness of chloride salts and abrasive-chloride salt mixtures for ice removal. It was also desired to study the storage characteristics of sodium chloride, calcium chloride and mixtures of these materials. Controlled field ice removal tests were run on 15 combinations of materials within three temperature ranges. Data were collected on thickness of ice; actual quantity and location of chemical or abrasive applied; and periodic condition of the ice with regard to amount of ice removed. The outdoor storage characteristics of seven bulk materials and one packaged material under a light polyethylene sheeting were studied. The materials were sampled for moisture, crusting and caking for a period of 10 months.

Contains a statistical report of the expenditures of the State Highway Department for the year 1923 with charts showing federal aid appropriations to Minnesota, construction on trunk highways by the state, distribution of trunk highway maintenance expenditures, analysis of trunk highway mileage, status of trunk highway mileage by counties, 1923 accomplishment report on trunk highway maintenance, analysis of maintenance expenditures by class and item, analysis of maintenance expenditures by commodity, traffic observations on trunk highways, summary of laboratory tests on materials, statement of expenditures, construction on state aid roads, the status report of federal aid payments on federal aid projects, maintenance expenditures on state aid roads, condition of state aid roads, abstract of annual reports on trunk highway expenditures, abstract of annual reports on state aid road expenditures. Submitted by Charles M. Babcock, Commissioner of Highways. [82 pp.]

Contains a report of the expenditures and achievements of the State Highway Department for the year 1922, road construction and maintenance, bridge construction and maintenance, road equipment, surplus war material, snow removal, trunk highway marking, traffic census, tests and inspection, highway offices and buildings, accounts, federal aid appropriations, construction on trunk highways by the counties, distribution of trunk highway maintenance expenditures, analysis of maintenance expenditures by commodity, analysis of maintenance expenditures by class and item, status of trunk highway mileage by counties, analysis of trunk highway mileage, traffic census observations on trunk highways-average number of vehicles per day, summary of laboratory tests on materials, Minnesota Highway Department financial statement, construction on state roads, state aid road and trunk highway construction upon which federal aid is applied, maintenance expenditures on state aid roads, abstract of annual reports on trunk highway and state aid road expenditures, condition of state aid roads, photos of roads and bridges, of Minnesota Highway Department-Central Office, main floor, drafting room, garage, machine shop, stock room, of Engineers' Convention Auditorium. Submitted by Charles M. Babcock, Commissioner of Highways. [117 pp.]

Contains charts showing state construction on trunk highways, construction by the counties on state trunk highways, distribution of 1921 trunk highway maintenance expenditures, analysis of expenditures on trunk highway maintenance work ending 1921, status of trunk highway mileage by counties, analysis of trunk highway mileage, 1921 traffic census observation on trunk highways average number of vehicles per day, performance and cost of operation of state owned gravel truck fleets, departments expenditures, allotment of state air road funds, construction on state roads, state and road and trunk highway construction upon which federal aid is applied, maintenance expenditures on state aid roads, abstract of annual reports on state aid road expenditures, status of improvement of state aid roads, a colored photo of State Highway no. 7. Submitted by Charles M. Babcock, Commissioner of Highways. [64 pp.]