Purpose:
Purpose of Strategic Services is to help create an organization that is Accountable, Responsive,
and Limited by providing tools and concepts for management decision-making.
Achieve Objectives By:
Collaborating, creating, developing, training, consulting, coaching and assisting in the
deployment of the Strategic Objectives, new ideas, and public business practices to all levels of
the organization.
Minnesota's Bridge Replacement Program has reached a critical juncture. Until now it has been successful in removing critical bridge deficiencies. However, without a significant influx of bridge funding, the task of preserving Minnesota's bridge system will be increasingly difficult.
This is due to a set of evolving issues, among which are included:
- By current Federal criteria, 5,281 (27 per cent) of Minnesota's 19,492 bridges are deficient. To reduce that backlog, as well as satisfy anticipated annual replacement needs would require an accelerated bridge replacement program over the next twenty years.
- Many of the bridges becoming and expected to become deficient within the next twenty years are older, larger, and more complicated than deficient bridges dealt with in the past.
- In twenty years, 61 per cent of Minnesota's bridges ..most built immediately following World War II ..will be reaching the end of their useful life.
These bridge improvement guidelines have been prepared by the Bridges and Structures Section and serve as a modification and update of the "1976 Report and Resulting Policy for Protection of Concrete Bridge Decks" and the "1977 Interim Policy for Protection of Concrete Bridge Decks". These guidelines have been formulated on a fiscal year basis to coincide with current programming procedures and project development practices.
The purpose of the Minnesota Bikeway Facility Design Manual is to provide engineers, planners, and designers with a primary source to implement the Minnesota Department of Transportation (Mn/DOT's) vision and mission for bicycle transportation in Minnesota. This manual also provides citizens, developers, and others involved in the transportation planning process, guidance on the critical design and planning elements to promote bicycle safety, efficiency, and mobility.
In September 1978, a Mn/DOT Task Force was established to conduct an in-depth analysis of rehabilitation measures for the 5.2 mile section of l-92 (see map, page 9) continuously reinforced concrete pavement (CRCP) located between Snelling Avenue in St. Paul and the Lowry Hill Tunnel in Minneapolis. The pavement is rapidly deteriorating due to ruptures of the reinforcing steel and spalling of the driving surface. This section of highway averages 30,000 vehicles per day. The rehabilitation of this pavement will have significant impacts. during construction in terms of social and economic cost to the traffic user and public served by the facility. In addition, the magnitude of the rehabilitation will have a major impact on the financial resources of Mn/DOT.
Because of the impacts, Mn/DOT management, felt it imperative to investigate and evaluate all possible measures in terms of design, engineering, project staging, timing, and cost. This report discusses the findings of the Task Force.
Spring is a critical period for Minnesota's roads because the roadbed soils and aggregate base materials are in a weakened state during and after the thawing process. Spring load restrictions (SLR) are used as a preservation strategy to reduce damage, thereby protecting Minnesota's investment in the infrastructure. However, the imposition of spring load restrictions impacts industry, both in their operations, and financially.
While it is clear that spring load restrictions benefit the infrastructure, there are two issues of which little is known: (1) the economic impacts that result when access to the transportation system is restricted and (2) extent of enforcement efforts.
The development of the Spring Load Restrictions Task Force was in response to 1999 legislation requiring the Commissioner of Transportation to establish a task force to study spring load restrictions and report to the legislature its findings and any recommendations for legislative action by February 1,2000. The legislation also calls for task force members that represent many interests including aggregate and readymix producers, agriculture, waste haulers, construction, and logging. Other members representing local agencies, associations, and enforcement have also been included.
The task force objectives were to study the current status of spring load restrictions in the state of Minnesota, explore the economic impacts of the load restrictions, and report the findings to the legislature.
This report is the result of the study made in 1978 concerning the method of pavement selection to be used by the Department of Transportation and an in-depth review made in 1981-82 by members of the original Task Force (as much as possible) of the factors utilized in the process to determine if they remained valid, required any modification, or if additional items should be considered in the pavement selection method. Included in this report are the conclusions, recommendations, the detailed study, appendices, references and bibliographies.
This report replaces the 1978 Report on Mn/DOT's Pavement Selection Method as a working document; however, because of its detailed nature, the 1978 Report does contain much significant information concerning the investigations made at that time prior to instituting the process that continues be used by Mn/DOT with the modification recommended by the 1981-82 Task Force and subsequently adopted by Mn/DOT.
This study evaluates methods used to reduce the amount of reflective cracking in new asphalt concrete overlays on existing PCC pavements. Methods being studied include asphalt-rubber interlayers as stress absorbing membrane interlayers (SAMI), cracking of PCC pavements before overlay and variable thicknesses of asphalt concrete overlays. To date only increased thickness of asphalt concrete overlays has significantly retarded reflective cracks. This report is an interim report and additional information is expected with time.
The life span of a roadway structure (underlying soil, gravel base, and road surfacing) is primarily influenced by three factors; structure strength, the number of trucks, and the weight of the trucks. Each axle load on a pavement takes away part of the pavement's life. Each unique pavement can take a given number of fatigue or stress cycles from the trucks before that pavement becomes structurally inadequate. In order to understand this interaction between loads and road structures, we need a common denominator for the truck traffic to define the damaging effects of the various weight levels. Such a common traffic damage identifier is needed since all roads carry completely mixed traffic of smallest cars to large trucks.
Most states, including Minnesota, now use an expression of N18 - translated mathematically it means the number of equivalent 18,000 Ib. single axle loads. Through years of research we've determined the amount of roadway damage done by any axle weight. A graph (Figure 1) and Table 1 will help to describe this relative damage effect.
Ideally, the type of pavement chosen for highway construction projects is the product of an analysis resulting in the most favorable combination of economic and engineering factors expressed in terms of the lowest annual cost per mile of road. Circumstances make the analysis somewhat less than ideal because inherent in the procedure is the need to make assumptions about future maintenance and costs in order to compare alternatives over equal periods of time. This report is a critical review of the pavement selection process as practiced by the Minnesota Department of Transportation. The study was conducted by the Research and Standards Section in response to an assignment made on June 23, 1975 by the Director of Materials, Research and Standards Office who also serves as chairman of the Pavement Selection Committee. The report presents a resume' of current practice together with analysis and recommendations for improvements in the process.
