Download or read book Development of a TL 3 F shape Temporary Concrete Median Barrier written by Ronald K. Faller and published by . This book was released on 1996 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work zones often require the use of temporary concrete barriers (TCBs) within a limited area to provide protection for construction workers. In situations where an existing guardrail is immediately adjacent to the construction hazards that need to be shielded, highway designers must either connect the guardrail to the temporary barrier or replace it with TCB. Although interconnecting the two barrier systems represents the more convenient option, at present no suitable solutions have been made available. A transition from guardrail to temporary barriers may not need to be nearly as stiff as a conventional approach transitions. However, it must provide sufficient stiffness and strength to prevent pocketing as well as to shield the end of the concrete barrier to prevent serious wheel snag. In addition, considerations must be made for transitioning from the TCB to the guardrail, anchoring the TCB system, and the potential use of tie-downs to limit TCB deflection. TCBs are connected and transitioned to many types of barriers. Unfortunately, little effort has been devoted to this issue. The only transitions previously developed have been between TCBs and safety shaped concrete barriers and TCBs and permanent concrete median barriers. Transitions between TCBs and other common barrier types, such as guardrail, have typically not been full-scale crash tested and may pose a serious hazard to motorists during an impact. Transitions between two barrier types generally are designed with the assumption that it is more critical to transition from a less stiff barrier to a stiffer barrier due to concerns for pocketing and snag on the stiffer barrier system. However, in the case of a TCB system, design of the transition can be more complex. Design of a transition between TCB and guardrail must consider several factors: (1) Connection of the guardrail on the upstream or downstream end of the TCB system - The location of the guardrail on either the upstream or downstream end of the transition will largely affect the transition along with other factors. For example, the attachment of the guardrail to the downstream end of an unanchored, free-standing TCB system would require a transition. This could be as simple as using tie-down anchorages on the TCB segments to increase their stiffness prior to the guardrail attachment. Conversely, attachment of the guardrail to the upstream end of a free-standing, TCB system would require a transition as well. However, this type of transition would require stiffening the guardrail as it approached the TCB. (2) Anchorage of the end of the TCB system - The location and design of the end anchorage for the TCB system will largely determine the stiffness of the TCB end as compared to the guardrail as well as the transition configuration. (3) Free-standing barrier vs. tie-down anchorage - The stiffness of the TCB section varies depending on whether the barrier segments use any form of tie-down anchorage. The design of the transition between the rail and the TCB would change depending on whether the barrier segments were free-standing or anchored. (4) Direction of traffic - The transition design may depend on the potential for two-way traffic or reverse impacts. Due to the wide range of factors affecting the design of a TCB to guardrail transition, it is necessary to develop a better understanding of the most common and most critical transition installations. Then, a transition design could be developed to meet those needs. It is anticipated that this transition design would be developed around the F-shape, TCB segment and the recently developed Midwest Guardrail System (MGS). The research study recommended herein would primarily be directed toward improving the safety and minimizing risk for the motoring public traveling within our nation's work-zones and on our highways and roadways. More specifically, this project would address the goal of the Smart Work Zone Deployment Initiative, which is "to develop improved methods and products for addressing safety and mobility in work zones by evaluating new technologies and methods, thereby enhancing safety and efficiency of traffic operations and highway workers. The project is a public/private partnership between the sponsoring public transportation agencies in several Midwestern States, the Federal Highway Administration (FHWA), private technology providers and university transportation researchers." The overall objective of this research effort is to develop a MASH TL-3 transition design between TCBs and the MGS. The design of the transition would focus on a representative selection of state departments of transportation (DOTs) highest priority configuration. Due to the large number of unknowns, this phase of the project will focus on the development of design concepts for the highest priority transition need. Full-scale crash testing of the proposed transition design is not a part of this project and may be performed in a future phase of the project. This research effort will begin with identifying and quantifying the most pressing TCB to guardrail transition needs. Although a need to develop configurations for most, if not all, of the TCB to guardrail transition needs may exist, this project will address the highest priority need. Thus, the state DOTs of the Midwest States Pooled Fund Program will be surveyed to identify the highest priority TCB to guardrail transition need. After the critical transition need is identified, potential transition concepts and prototype designs will be brainstormed. Computer simulations with LS-DYNA, a non-linear explicit finite element code, will be used to investigate and evaluate the concepts and prototype designs. CAD details for the proposed transition design will be prepared. A summary report detailing the research effort will be compiled and will include recommendations for future full-scale crash testing of the TCB to guardrail transition as well as recommendations for further development of TCB to guardrail transitions. The research study is directed toward improving the safety by minimizing the risk for the motoring public traveling within our nation's work-zones and on our highways and roadways. Since W-beam guardrail has proven to provide better safety performance than temporary concrete barriers, the development of an effective transition between the two can help preserve guardrails outside the immediate work-zone area, thus providing an overall higher level of safety for motorists. The new transition would also eliminate the use of an unproven connection between guardrail and temporary barriers. Further, limiting the use of temporary concrete barriers strictly to the work zone area will also minimize the traffic disruption that these barriers can create to motorists passing in work zones. Following the development efforts, a research report will be prepared that summarizes the results of the study. If warranted, a formal paper will be prepared and submitted for publication in a refereed journal, such as a Transportation Research Record, so that dissemination and distribution of the final research results will provide the most significant impact in terms of safety benefit for the motoring public
Download or read book Roadside Design Guide written by American Association of State Highway and Transportation Officials. Task Force for Roadside Safety and published by . This book was released on 1989 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Tie down System for Temporary Concrete Barriers written by and published by . This book was released on 2002 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report details the development and testing of an NCHRP Report 350 compliant tie-down system for use with F-shape temporary concrete barriers. Development of the tie-down system began with the creation and evaluation of several design concepts. Following the researchers' evaluation of the design prototypes, the steel strap tie-down concept was selected for further study.
Download or read book Evaluation of Roadside Features to Accommodate Vans Minivans Pickup Trucks and 4 wheel Drive Vehicles written by Hayes E. Ross and published by Transportation Research Board. This book was released on 2002 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Temporary Barrier System for Off road Applications written by Kenneth H. Addink and published by . This book was released on 1998 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The safety shape portable concrete barrier (PCB) has been approved for use when placed on a bituminous or concrete pad. Construction personnel would like to use PCBs in temporary situations along roadways where the use of a bituminous or concrete pad is impractical and costly. However, when PCBs are placed on soil foundations with no anchorage, they tend to dig into the soil, causing the barrier sections to rotate or overturn. The objective of this research was to develop a device which will allow temporary PCBs placed on soil foundations to translate without significant rotation when impacted by errant vehicles. This device was developed and successfully tested to Test Level 3 of the National Cooperative Highway Research Program (NCHRP) Report No. 350.
Download or read book Development of a Retrofit Low deflection Temporary Concrete Barrier System written by Robert W. Bielenberg and published by . This book was released on 2014 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book HEC River Analysis System HEC RAS written by Gary W. Brunner and published by . This book was released on 1994 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transportation Research Record written by and published by . This book was released on 1974 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Policy on Geometric Design of Highways and Streets 2018 written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Highway engineers, as designers, strive to meet the needs of highway users while maintaining the integrity of the environment. Unique combinations of design controls and constraints that are often conflicting call for unique design solutions. A Policy on Geometric Design of Highways and Streets provides guidance based on established practices that are supplemented by recent research. This document is also intended as a comprehensive reference manual to assist in administrative, planning, and educational efforts pertaining to design formulation
Download or read book Roadside Safety Features and Hydraulic Hydrology and Water Quality Issues written by National Research Council (U.S.). Transportation Research Board and published by . This book was released on 2000 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation Research Record contains the following papers: Evaluation of portable concrete barriers using finite element simulation (Marzougi, D, Bahouth, G, Eskandarian, A, Meczkowski and Taylor, H); Impact performance of the G4(1W) and G4(2W) guardrail systems : comparison under NCHRP report 350 test 3-11 conditions (Plaxico, CA, Ray, MH and Hiranmayee, K); Long-span guardrail system for culvert applications (Faller, RK, Sicking, DL, Polivka, KA, Rohde, JR and Bielenberg, BW); Transitions from guardrail to bridge rail that meet safety performance requirements (Buth, CE, Menges, WL, and Bligh, RP); Performance of breakaway cable and modified eccentric loader terminals in Iowa and North Carolina : in-service evaluation (Ray, MH and Hopp, JA); Safety effectiveness of upgrading guardrail terminals to NCHRP reports 350 standards (Ray, MH); Design and development of steel breakaway posts (Sicking, DL, Rohde, JR and Reid, JD); Evaluating human risk in side impact collisions with roadside objects (Ray, MH and Hiranmayee, K); In-service, performance-based roadside design policy : preliminary insights from Washington State's bridge rail study (Shankar, VN, Albin, RB, Milton, JC and Nebergall, M); Test level 4 bridge rails (Buth, CE, Menges, WL and Williams, WF); Estimation of time of concentration for Maryland streams (Thomas, WO, Monde, MC and Davis, SR); Temporal variations in heavy metal partitioning and loading in urban highway pavement sheet flow : implications for in situ treatment design (Sansalone, JJ and Glenn, DW); California Department of Transportation statewide storm water management program (Johnston, J, Yamaguchi, H and Frankel, A).
Download or read book Guidelines for Shielding Bridge Piers written by Malcolm H. Ray and published by . This book was released on 2018 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Public Roads written by and published by . This book was released on 2000 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book LRFD Guide Specifications for the Design of Pedestrian Bridges written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2009 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AASHTO Guide Specifications for LRFD Seismic Bridge Design written by and published by AASHTO. This book was released on 2011 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work offers guidance on bridge design for extreme events induced by human beings. This document provides the designer with information on the response of concrete bridge columns subjected to blast loads as well as blast-resistant design and detailing guidelines and analytical models of blast load distribution. The content of this guideline should be considered in situations where resisting blast loads is deemed warranted by the owner or designer.
Download or read book Transforming the Workforce for Children Birth Through Age 8 written by National Research Council and published by National Academies Press. This book was released on 2015-07-23 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: Children are already learning at birth, and they develop and learn at a rapid pace in their early years. This provides a critical foundation for lifelong progress, and the adults who provide for the care and the education of young children bear a great responsibility for their health, development, and learning. Despite the fact that they share the same objective - to nurture young children and secure their future success - the various practitioners who contribute to the care and the education of children from birth through age 8 are not acknowledged as a workforce unified by the common knowledge and competencies needed to do their jobs well. Transforming the Workforce for Children Birth Through Age 8 explores the science of child development, particularly looking at implications for the professionals who work with children. This report examines the current capacities and practices of the workforce, the settings in which they work, the policies and infrastructure that set qualifications and provide professional learning, and the government agencies and other funders who support and oversee these systems. This book then makes recommendations to improve the quality of professional practice and the practice environment for care and education professionals. These detailed recommendations create a blueprint for action that builds on a unifying foundation of child development and early learning, shared knowledge and competencies for care and education professionals, and principles for effective professional learning. Young children thrive and learn best when they have secure, positive relationships with adults who are knowledgeable about how to support their development and learning and are responsive to their individual progress. Transforming the Workforce for Children Birth Through Age 8 offers guidance on system changes to improve the quality of professional practice, specific actions to improve professional learning systems and workforce development, and research to continue to build the knowledge base in ways that will directly advance and inform future actions. The recommendations of this book provide an opportunity to improve the quality of the care and the education that children receive, and ultimately improve outcomes for children.
Download or read book TL 5 Development of 42 and 51 in Tall Single faced F shape Concrete Barriers written by and published by . This book was released on 2004 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Highway Subdrainage Design written by Lyle K. Moulton and published by . This book was released on 1980 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
