PERFORMANCE ANALYSIS OF WELCH PRODUCTS RECYCLED RUBBER SPACER BLOCK

The Midwest Roadside Safety Facility was contracted by Will Stein of the Iowa Department of Transportation to conduct dynamic bogie testing of a recyclable rubber guardrail spacer block manufactured by Welch Products, Inc. The scope of the work included the setup of both a standard, wood guardrail post blockout and the Welch Products recycled rubber blockout on a standard W150x13.5 steel post, as well as two component tests using a bogie vehicle. The bogie tests were conducted in accordance with previously accepted procedures to evaluate the performance of guardrail post blockouts made of non-standard materials

PERFORMANCE ANALYSIS OF WELCH PRODUCTS RECYCLED RUBBER SPACER BLOCK

The Midwest Roadside Safety Facility was contracted by Will Stein of the Iowa Department of Transportation to conduct dynamic bogie testing of a recyclable rubber guardrail spacer block manufactured by Welch Products, Inc. The scope of the work included the setup of both a standard, wood guardrail post blockout and the Welch Products recycled rubber blockout on a standard W150x13.5 steel post, as well as two component tests using a bogie vehicle. The bogie tests were conducted in accordance with previously accepted procedures to evaluate the performance of guardrail post blockouts made of non-standard materials

DEVELOPMENT AND EVALUATION OF A TIE-DOWN SYSTEM FOR THE REDESIGNED F-SHAPE CONCRETE TEMPORARY BARRIER

Often, temporary barriers are used in applications where it is desired that their deflection during vehicular impact be limited. One such application is in the installation of temporary barriers placed adjacent to the edge of a concrete bridge deck in order to maximize lane width. Acceptable tie-down systems for temporary barriers have previously been developed, but there are concerns when the barriers and tie-down systems are used on bridges that are reconstructed in stages and where very little tolerance in barrier deflection is allowable. Therefore, a rigid tie-down system was developed that minimizes barrier deflections. For this system, the original Kansas temporary barrier was redesigned in order to strengthen the barrier around the tie-down holes and to standardize the barriers for use in adjacent states and in various temporary and tied-down configurations. The tie-down anchor system fastened the traffic-side of the barriers to the concrete bridge deck with three 29-mm (1.125-in.) diameter ASTM A307 anchor bolts with heavy hex nuts and 76-mm (3-in.) x 76-mm (3-in.) x 13-mm (0.5-in.) thick washers. The research study included one full-scale vehicle crash test, using a 3⁄4-ton pickup truck. The full-scale test, with an impact speed of 99.8 km/hr (62.0 mph) and an impact angle of 25.3 degrees, was conducted and reported in accordance with the requirements specified in the National Cooperative Highway Research Program (NCHRP) Report No. 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features. The safety performance of the tie-down anchor system for use with concrete bridge decks and the redesigned F-shape temporary concrete barrier was determined to be acceptable according to the Test Level 3 (TL-3) evaluation criteria specified in NCHRP Report No. 350

DEVELOPMENT AND EVALUATION OF A TIE-DOWN SYSTEM FOR THE REDESIGNED F-SHAPE CONCRETE TEMPORARY BARRIER

Often, temporary barriers are used in applications where it is desired that their deflection during vehicular impact be limited. One such application is in the installation of temporary barriers placed adjacent to the edge of a concrete bridge deck in order to maximize lane width. Acceptable tie-down systems for temporary barriers have previously been developed, but there are concerns when the barriers and tie-down systems are used on bridges that are reconstructed in stages and where very little tolerance in barrier deflection is allowable. Therefore, a rigid tie-down system was developed that minimizes barrier deflections. For this system, the original Kansas temporary barrier was redesigned in order to strengthen the barrier around the tie-down holes and to standardize the barriers for use in adjacent states and in various temporary and tied-down configurations. The tie-down anchor system fastened the traffic-side of the barriers to the concrete bridge deck with three 29-mm (1.125-in.) diameter ASTM A307 anchor bolts with heavy hex nuts and 76-mm (3-in.) x 76-mm (3-in.) x 13-mm (0.5-in.) thick washers. The research study included one full-scale vehicle crash test, using a 3⁄4-ton pickup truck. The full-scale test, with an impact speed of 99.8 km/hr (62.0 mph) and an impact angle of 25.3 degrees, was conducted and reported in accordance with the requirements specified in the National Cooperative Highway Research Program (NCHRP) Report No. 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features. The safety performance of the tie-down anchor system for use with concrete bridge decks and the redesigned F-shape temporary concrete barrier was determined to be acceptable according to the Test Level 3 (TL-3) evaluation criteria specified in NCHRP Report No. 350

COMPLIANCE TESTING OF A BULLNOSE MEDIAN BARRIER SYSTEM: NCHRP REPORT 350

A new bullnose guardrail system for the treatment of median hazards was developed and successfully crash tested according to the safety criteria set forth in NCHRP Report 350. The new system consists of a nose section 4500 mm wide by 4824 mm long, comprising three sections of curved thrie beam guardrail attached to parallel sides of thrie beam guardrail 4500 mm apart. The nose section was designed to safely capture and contain vehicles impacting the nose. Two 6 x 25 steel cables were attached behind the top two humps of the nose section to ensure vehicle capture in the event the thrie beam ruptured. Additionally, the first five sections of guardrail had horizontal slots cut in the valleys of the rail to improve vehicle capture and reduce the formation of large kinks that could pose a threat to a vehicle as the system deformed to absorb an impact. The research study included computer simulation modeling using LS-DYNA and full-scale vehicle testing using 2000-kg pickup trucks and 820-kg small cars in accordance with the Test Level 3 safety performance requirements specified in NCHRP Report 350. Nine full-scale crash tests were performed on the new system. Several changes were made to the bullnose system to improve its safety performance during the course of the testing and development

LONG-SPAN GUARDRAIL SYSTEM FOR CULVERT APPLICATIONS

A long-span guardrail for use over low-fill culverts was developed and successfully crash tested. The guardrail system was configured with 30.48 m of nested, 12-gauge W-beam rail and centered around a 7.62-m-long unsupported span. The nested W-beam rail was supported by 16 W152 x 13.4 steel posts and 6 standard CRT posts, each with two 150-mm x 200 x 360 mm wood block-outs. Each post was 1830 mm long. Post spacings were 1905 mm on center, except for the 7.62-m spacing between the two CRT posts surrounding the long span. The research study included computer simulation modeling with Barrier VII and full-scale vehicle crash testing, using 3/4-ton (680-kg) pickup trucks in accordance with the Test Level 3 (TL-3) requirements specified in NCHRP Report 350. Three full-scale vehicle crash tests were performed. The first test was unsuccessful because of severe vehicle penetration into the guardrail system. This penetration resulted from a loss of rail tensile capacity during vehicle redirection when the swagged fitting on the cable anchor assembly failed. A second test was performed on the same design, which contained a new cable anchor assembly. During vehicle redirection, the pickup truck rolled over and the test was considered a failure. The long-span system was subsequently redesigned to incorporate double block-outs on the CRT posts and crash tested again. Following the successful third test, the long-span guardrail system was determined to meet TL-3 criteria