150 resultados para CONSTRUCTION WORKERS


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Public travel by motor vehicles is often necessary in road and street sections that have been officially closed for construction, repair, and/or other reasons. This authorization is permitted in order to provide access to homes and businesses located beyond the point of closure. The MUTCD does address appropriate use of specific regulatory signs at the entrance to closed sections; however, direct guidance for temporary traffic control measures within these areas is not included but may be needed. Interpretation and enforcement of common practices may vary among transportation agencies. For example, some law enforcement officers in Iowa have indicated a concern regarding enforcement and jurisdiction of traffic laws in these areas because the Code of Iowa only appears to address violations on roadways open to “public travel.” Enforcement of traffic laws in closed road sections is desirable to maintain safety for workers and for specifically authorized road users. In addition, occasional unauthorized entry by motor vehicles is experienced in closed road areas causing property damage. Citations beyond simple trespass may be advisable to provide better security for construction sites, reduce economic losses from damage to completed work, and create safer work zones.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This phase of the electronic collaboration project involved two major efforts: 1) implementation of AEC Sync (formerly known as Attolist), a web-based project management system (WPMS), on the Broadway Viaduct Bridge Project and the Iowa Falls Arch Bridge Project and 2) development of a web-based project management system for bridge and highway construction projects with less than $10 million in contract value. During the previous phase of this project (fiscal year 2010), the research team helped with the implementation process for AEC Sync and collected feedback from the Broadway Viaduct project team members before the start of the project. During the 2011 fiscal year, the research team collected the post-project surveys from the Broadway Viaduct project members and compared them to the pre-project survey results. The results of the AEC Sync implementation on the Broadway project were positive. The project members were satisfied with the performance of the AEC Sync software and how it facilitated document management and its transparency. In addition, the research team distributed, collected, and analyzed the pre-project surveys for the Iowa Falls Arch Bridge Project. The implementation of AEC Sync for the Iowa Falls Arch Bridge Project appears to also be positive, based on the pre-project surveys. The fourth phase of this electronic collaboration project involves the identification and implementation of a WPMS solution for smaller bridge and highway projects. The workflow for the shop drawing approval process for sign truss projects was documented and used to identify possible WPMS solutions. After testing and evaluating several WPMS solutions, Microsoft SharePoint Foundation’s site pages were selected to be pilot-tested on sign truss projects. Due to the limitation on the SharePoint license that the Iowa Department of Transportation (DOT) has, a file transfer protocol (FTP) site will be developed alongside this site to allow contractors to upload shop drawings to the Iowa DOT. The SharePoint site pages are expected to be ready for implementation during the 2012 calendar year.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Most counties have bridges that are no longer adequate, and are faced with large capital expenditure for replacement structures of the same size. In this regard, low water stream crossings (LWSCs) can provide an acceptable, low cost alternative to bridges and culverts on low volume and reduced maintenance level roads. In addition to providing a low cost option for stream crossings, LWSCs have been designed to have the additional benefit of stream bed stabilization. Considerable information on the current status of LWSCs in Iowa, along with insight of needs for design assistance, was gained from a survey of county engineers that was conducted as part of this research (Appendix A). Copies of responses and analysis are included in Appendix B. This document provides guidelines for the design of LWSCs. There are three common types of LWSCs: unvented ford, vented ford with pipes, and low water bridges. Selection among these depends on stream geometry, discharge, importance of road, and budget availability. To minimize exposure to tort liability, local agencies using low water stream crossings should consider adopting reasonable selection and design criteria and certainly provide adequate warning of these structures to road users. The design recommendations included in this report for LWSCs provide guidelines and suggestions for local agency reference. Several design examples of design calculations are included in Appendix E.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Rebuild Iowa Office (RIO) continues to coordinate the state‘s recovery effort from the storms, tornadoes and floods of 2008. Much has been accomplished since the Office‘s last quarterly report was issued in July 2010. State funding has been disbursed to help Iowans with unmet needs and housing. Local governments and entities are utilizing millions of federal dollars so thousands of disaster-impacted homeowners can be offered a buyout. More infrastructure projects are under construction and new neighborhoods are being built with mitigation efforts in mind. However, as Iowa continues to celebrate many successes along the road to recovery, it must also address the numerous challenges that are encountered along the path. Recovering from the state‘s largest disaster must be looked at as a marathon, not a sprint. Over the past three months, the RIO has especially remained focused on helping small business owners impacted by the 2008 disasters. Many disaster-affected businesses have reopened their doors, however their debt load continues to be overwhelming and many still struggle with the timeliness of the disbursement of funds. This report describes how programs and recent modifications are working to assist recovering businesses. This report contains updates on housing progress while outlining the complexities behind certain programs and the bottlenecks communities are facing due to strict federal guidelines for implementation. This following pages also describe how Iowa is implementing Smart Planning principles, publicizing flood awareness through outreach efforts and preparing a blueprint for the state to follow when future disasters occur. As always, the RIO recognizes and thanks the countless leaders and front-line workers from local, regional, state and federal government, businesses, non-profit organizations and private citizens that have provided input, support and leadership. Their dedication to Iowa‘s disaster recovery has made the plans and projects on the following pages possible.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

General principles • Everyone at the construction site, particularly foremen and supervisors, is responsible for recognizing and troubleshooting potential problems as they arise. • Batches of concrete should be consistent and uniformly mixed. • A major cause of pavement failure is unstable subgrade. The subgrade should consist of uniform material, and the subgrade system must drain well. • Dowel bars are important for load transfer at transverse joints on pavements with high truck volumes. Dowels must be carefully aligned, horizontally and vertically, to prevent pavement damage at the joints. • Stringlines control the slipform paver’s horizontal and vertical movement and ensure a smooth pavement profile. Once stringlines are set, they should be checked often and not disturbed. • Overfinishing the new pavement and/or adding water to the surface can lead to pavement surface problems. If the concrete isn’t sufficiently workable, crews should contact the project manager. Changes to the mixture or to paver equipment may reduce the problem. • Proper curing is critical to preventing pavement damage from rapid moisture loss at the pavement surface. • A well spaced and constructed system of joints is critical to prevent random cracking. • Joints are simply controlled cracks. They must be sawed during the brief time after the pavement has gained enough strength to prevent raveling but before it begins to crack randomly (the “sawing window”). • Seasonal and daily weather variations affect setting time and other variables in new concrete. Construction operations should be adjusted appropriately.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document provides language that can be used by an Owner-Agency to develop materials and construction specifications with the objective of reducing tire/pavement noise. While the practices described herein are largely prescriptive, they have been demonstrated to increase the likelihood of constructing a durable, quieter concrete surface.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document provides language that can be used by an Owner-Agency to develop materials and construction specifications with the objective of reducing tire/pavement noise. While the practices described herein are largely prescriptive, they have been demonstrated to increase the likelihood of constructing a durable, quieter concrete surface. Guidance is provided herein for texturing the concrete surface since texture geometry has a paramount effect on tire/pavement noise. Guidance for curing is also provided to improve strength and durability of the surface mortar, and thus to improve texture durability.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document provides language that can be used by an Owner-Agency to develop materials and construction specifications with the objective of reducing tire/pavement noise. While the practices described herein are largely prescriptive, they have been demonstrated to increase the likelihood of constructing a durable, quieter concrete surface. Guidance is provided herein for texturing the concrete surface since texture geometry has a paramount effect on tire/pavement noise. Guidance for curing is also provided to improve strength and durability of the surface mortar, and thus to improve texture durability.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Most counties have bridges that are no longer adequate, and are faced with large capital expenditure for replacement structures of the same size. In this regard, low water stream crossings (LWSCs) can provide an acceptable, low cost alternative to bridges and culverts on low volume and reduced maintenance level roads. In addition to providing a low cost option for stream crossings, LWSCs have been designed to have the additional benefit of streambed stabilization. Considerable information on the current status of LWSCs in Iowa, along with insight of needs for design assistance, was gained from a survey of county engineers that was conducted as part of this research (Appendix A). Copies of responses and analysis are included in Appendix B. This document provides guidelines for the design of LWSCs. There are three common types of LWSCs: unvented ford, vented ford with pipes, and low water bridges. Selection among these depends on stream geometry, discharge, importance of road, and budget availability. To minimize exposure to tort liability, local agencies using low water stream crossings should consider adopting reasonable selection and design criteria and certainly provide adequate warning of these structures to road users. The design recommendations included in this report for LWSCs provide guidelines and suggestions for local agency reference. Several design examples of design calculations are included in Appendix E.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Most Iowa counties maintain low volume roads with at least one bridge or culvert that is structurally deficient or obsolete. In some counties the percentage of deficient drainage structures may be as high as 62%. Replacement with structures of similar size would require large capital expenditures that many counties cannot afford. Low water stream crossings (LWSCs) may be an acceptable lowcost alternative in some cases.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In July 2006, construction began on an accelerated bridge project in Boone County, Iowa that was composed of precast substructure elements and an innovative, precast deck panel system. The superstructure system consisted of full-depth deck panels that were prestressed in the transverse direction, and after installation on the prestressed concrete girders, post-tensioned in the longitudinal direction. Prior to construction, laboratory tests were completed on the precast abutment and pier cap elements. The substructure testing was to determine the punching shear strength of the elements. Post-tensioning testing and verification of the precast deck system was performed in the field. The forces in the tendons provided by the contractor were verified and losses due to the post-tensioning operation were measured. The stress (strain) distribution in the deck panels due to the post-tensioning was also measured and analyzed. The entire construction process for this bridge system was documented. Representatives from the Boone County Engineers Office, the prime contractor, precast fabricator, and researchers from Iowa State University provided feedback and suggestions for improving the constructability of this design.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed in 2007 over a stream. The bridge’s precast elements included precast cap beams and precast box girders. Precast element fabrication and bridge construction were observed, two precast box girders were tested in the laboratory, and the completed bridge was field tested in 2007 and 2008.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa DOT Office of Bridges and Structures. Black Hawk County (BHC) has developed a precast modified beam-in-slab bridge (PMBISB) system for use with accelerated construction. A typical PMBISB is comprised of five to six precast MBISB panels and is used on low volume roads, on short spans, and is installed and fabricated by county forces. Precast abutment caps and a precast abutment backwall were also developed by BHC for use with the PMBISB. The objective of the research was to gain knowledge of the global behavior of the bridge system in the field, to quantify the strength and behavior of the individual precast components, and to develop a more time efficient panel-to-panel field connection. Precast components tested in the laboratory include two precast abutment caps, three different types of deck panel connections, and a precast abutment backwall. The abutment caps and backwall were tested for behavior and strength. The three panel-to-panel connections were tested in the lab for strength and were evaluated based on cost and constructability. Two PMBISB were tested in the field to determine stresses, lateral distribution characteristics, and overall global behavior.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The need to construct bridges that last longer, are less expensive, and take less time to build has increased. The importance of accelerated bridge construction (ABC) technologies has been realized by the Federal Highway Administration (FHWA) and the Iowa Department of Transportation (DOT) Office of Bridges and Structures. This project is another in a series of ABC bridge projects undertaken by the Iowa DOT. Buena Vista County, Iowa, with the assistance of the Iowa Department of Transportation (DOT) and the Bridge Engineering Center (BEC) at Iowa State University, constructed a two-lane single-span precast box girder bridge, using rapid construction techniques. The design involved the use of precast, pretensioned components for the bridge superstructure, substructure, and backwalls. This application and demonstration represents an important step in the development and advancement of these techniques in Iowa as well as nationwide. Prior funding for the design and construction of this bridge (including materials) was obtained through the FHWA Innovative Bridge Research and Deployment (IBRD) Program. The Iowa Highway Research Board (IHRB) provided additional funding to test and evaluate the bridge. This project directly addresses the IBRD goal of demonstrating (and documenting) the effectiveness of innovative materials and construction techniques for the construction of new bridge structures. Evaluation of performance was formulated through comparisons with design assumptions and recognized codes and standards including American Association of State Highway and Transportation Officials (AASHTO) specifications.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Public agencies in Iowa are continually challenged with reduced staff levels, reduced budgets, and increased expectations for services provided. Responding to these demands requires a well-informed and coordinated team that includes professionals, supervisors, technicians, lead workers, and workers. Becoming a coordinated team requires the training and interaction to produce a common foundation to build upon. In 2007, a training program did not exist in the state to provide this level of training for existing or upcoming managers and leaders of public agencies. The Iowa Local Technical Assistance Program (LTAP), in conjunction with Iowa public agency representatives, set out to provide that foundation by developing the Iowa Public Employees Leadership Academy, which was renamed the Public Employees Leadership Institute in July 2011. The Institute is an on-demand, online training program designed to create better (or new) leaders and supervisors for Iowa’s public agencies. The Institute provides a curriculum to train the next generation of leaders, who will replace existing leaders when retirements occur. Through the Institute, Iowa LTAP will provide a coordinated, structured, non-credit educational program available for a modest fee. The techniques and skills offered through the Institute can apply to all who wish to develop or sharpen their leadership and management abilities. This will be true whether the participants are employed in the public or private sector. The 14 courses that were developed and are being offered are as follows: Supervisory Techniques and Skills, Team Development, Communications Skills, Leadership Skills, Community Service/Customer Orientation, Legal Understanding, Fundamentals of Government, Finance, Resource Management, Operations and Maintenance, Basic Management, Emergency Management, Project Management, and Winter Maintenance Management.