Fred wayne Klaiber

Iowa State University | ISU · Center for Bridge Engineering

The objective of this paper is to evaluate the response of High Density Polyethylene (HDPE) pipes under various backfill conditions and 24-in. (610mm) cover. Eight full-scale field tests were conducted on 36-in. diameter HDPE pipes from two manufacturers, which were tested with backfills ranging from very poor to excellent sand and glacial till. Th...

The objective of this paper is to enhance the application of larger diameter High Density Polyethylene (HDPE) pipes in medium or rural roads without any pavement layers while these pipes frequently experience standard truck loads. Culver ANalysis and DEsign (CANDE) was applied to simulate the static interaction of pipe structures and the surroundin...

The purpose of this investigation is to determine a technique for increasing the capacity of bridges to accommodate today's increase in loading. Strengthening existing steel stringers in composite, steel-beam, concrete-deck bridges by providing partial end restraint is shown to be feasible. The research program included a review of existing literat...

In the last decade, the use of fiber reinforced polymer (FRP) composites technology has emerged as an option in structural engineering and has shown its potential for structural applications in bridges. FRP composite materials are appealing in that they are highly resistant to corrosion, have a low weight, and have a high tensile strength. This pap...

In the last few years, extensive research has been done on the strengthening of concrete structures using fiber reinforced polymers (FRP) as externally bonded sheets or plates. A limited number of studies have also been performed on the strengthening of steel and steel–concrete composite structures. Constructing and testing steel–concrete composite...

An innovative structural system for pier columns is currently being investigated through a series of laboratory experiments. The columns and connections under investigation are comprised of precast concrete segments to accelerate construction. In addition, some of the columns being investigated employ elastic elements to self-center the columns aga...

New bridge systems are needed that will allow components to be fabricated off-site and transported to the bridge site for quick assembly with minimal disruption to the traveling public. Depending on the specific site conditions, the use of prefabricated bridge systems can minimize traffic disruption, improve work-zone safety, reduce the impact on t...

Strengthening and rehabilitation of structures is a major concern for researchers in the civil engineering community in recent years due to the aging of these structures and the need for effective methods of strengthening. This paper presents the results of an experimental study of the behavior of strengthened steel–concrete composite girders using...

Black Hawk County (BHC) has developed a precast modified beam-in-slab bridge (PMBISB) system for use with accelerated construction. Individual components of the system have been tested in the Iowa State University Structural Laboratory, and the overall system was tested in the field. Using the BHC system, the bridge superstructure can be assembled...

As a means of extending available resources, the Black Hawk County Engineer's Office, Black Hawk County, Iowa, has developed a precast bridge system specifically for low-volume roads with spans up to approximately 40 ft (12.19 m). The design, referred to as the precast modified beam-in-slab bridge (PMBISB), consists of four precast panels, which ar...

The precast channel bridge (PCB) was commonly constructed on Iowa's secondary roads approximately 40 years ago. Each PCB span consists of eight to 10 simply supported precast panels ranging in length from 19 to 36 ft. The panels resemble a steel channel in cross section; the web is orientated horizontally to form the roadway deck, and the vertical...

Many state, county, and local agencies have deteriorating short to medium span bridges. These bridges are commonly single span or multiple span continuous structures, and are composed of rolled or welded longitudinal steel stringers used as part of a continuous slabon- girder bridge. Most of these bridges continue to serve as an integral part of th...

Researchers at the Iowa State University (ISU) Bridge Engineering Center have developed the modified beam-in-slab bridge (MBISB) system as an alternative replacement for use on low-volume roads. The system consists of longitudinal steel girders with a concrete arched deck cast between the girders. Composite action between the concrete and steel is...

Although several superstructure design methodologies have been developed for low-volume road bridges by the Iowa State University Bridge Engineering Center, no standard abutment designs had been developed. Thus, there was need for an easy-to-use design methodology, generic abutment construction drawings, and other design aids for the more common su...

This project investigated the effectiveness of carbon fiber-reinforced polymer (CFRP) composite materials to strengthen an existing, structurally deficient steel girder bridge. The bridge selected for strengthening with the CFRP posttensioning system is a three-span continuous steel stringer bridge on IA-141 approximately 1.6 mi west of Bayard, Iow...

Accurately and effectively assessing the safe load-carrying capacity of bridges is a common problem that bridge owners face. Diagnostic testing can be especially beneficial for bridges that are part of an aging, rapidly decaying infrastructure. In addition, diagnostic testing can assess whether superloads can safely cross a bridge. When tested, bri...

Managers of most low-volume roads (LVR) face a deteriorating bridge population, and replacement is frequently the most cost-effective solution. With more structures needing replacement than available funds to do so, low-cost alternatives that are constructible in-house are a desirable option. The modified beam-in-slab bridge (MBISB) is one such alt...

Many short and medium span bridges are deteriorating due to age and environ-mental effects. A large percentage of these problem bridges are composite structures – steel lon-gitudinal stringers plus an integral reinforced concrete deck. Although these bridges are still in service, many need some level of strengthening due to increases in legal live...

One significant cause of deterioration of steel bridge structures is the corrosion due to extensive use of deicing salts in winter weather. The investigation presented in this paper focused on the behavior of steel composite beams damaged intentionally at their tension flange to simulate corrosion and then repaired with carbon fiber-reinforced poly...

Many state, county, and local agencies are faced with deteriorating bridge infrastructure composed of a large percentage of relatively short to medium span bridges. In many cases, these older structures are rolled or welded longitudinal steel stringers acting compositely with a reinforced concrete deck. Most of these bridges, although still in serv...

Repairing/replacing deficient bridges is a major challenge for transportation system managers and is magnified for Low Volume Road (LVR) systems where inadequate structures need replacing due to structural and functional deficiencies. To maximize limited replacement funds, some local governments employ in-house forces to reduce construction costs,...

This paper documents two projects funded through the Federal Highway Administration's Innovative Bridge Research and Construction (IBRC) program. The IBRC program was developed to assist bridge owners in applying emerging technologies in bridge engineering. In these projects, the Iowa Department of Transportation employed techniques for strengtheni...

The use of Railroad Flatcars (RRFCs) as the superstructure in low-volume bridges has been investigated in a research project at Iowa State University. These alternative bridges will enable county engineers to replace old, inadequate county bridges for less money and in a shorter construction time than required for a conventional bridge. A feasibili...

Every year many prestressed concrete (P/C) girder bridges in Iowa are damaged by overheight vehicles. Traditional P/C girder repair strategies include welded steel jackets, internal strand splices, and external post-tensioning. Unfortunately, these types of repairs are both labor intensive and vulnerable to future corrosion. One possible alternativ...

About one half of the approximately 600,000 highway bridges in the United States were built before 1940, and many have not been adequately maintained. Most of these bridges were designed for lower traffic volumes, smaller vehicles, slower speeds, and lighter loads than are common today. In addition, deterioration caused by environmental factors is...

Nearly half of the 587,000 bridges in excess of 6.1 m (20 ft) long on public roads in the United States are located off the Federal Aid System, are on local rural and urban roads or rural minor collectors, and are classified as off-system bridges. Approximately one-third of the off-system bridges are structurally deficient or functionally obsolete....

Funding for the repair and replacement of structurally deficient and functionally obsolete bridges is a nationwide problem. This problem is magnified for the managers of low-volume-road (LVR) systems who have limited budgets; thus, innovative replacement alternatives are always being sought. The beam-in-slab bridge (BISB) is an alternative replacem...

The use of railroad flatcars (RRFCs) as the superstructure in low-volume bridges has been investigated in, a research project at Iowa State University. These alternative bridges should enable county engineers to replace old, inadequate county bridges for less money and in a shorter construction time than required for a conventional bridge. Capital...

The precast channel bridge (PCB) is a short span bridge that was commonly used on Iowa's secondary roads approximately forty years ago. Each PCB consists of eight to ten simply supported precast panels ranging in length from 5.8m to 11.0m. The panels resemble a steel channel in cross-section; the web is orientated horizontally and forms the roadway...

CANDE is one of the most commonly used programs for analysis of buried pipe; however, CANDE is limited to applications with small deflections. This limitation is typically not problematic, but there are some instances in which analysts may be interested in large-deflection behavior. This limitation led to the consideration of other analysis tools....

Re-cent reports indicate that a significant number of the nation's bridges are either structurally deficient or functionally obsolete. A large number of these bridges are on the secondary road system and fall under the jurisdiction of county engineers with limited budgets and engineering staff. In response to this problem, a bridge replacement syst...

A series of diagnostic load tests performed on two prestressed concrete bridges located in western Iowa are discussed. The bridges are dual prestressed concrete-I-beam structures. In June 1996, an overheight vehicle struck the westbound structure and caused significant loss of section and cracking. As a result of the severity of the damage and beca...

In response to problems with corrugated metal pipe (CMP) culvert uplift failures caused by unbalanced inlet hydraulic loading, full-scale field testing and numerical analysis were undertaken to develop a rational design methodology for CMP inlet tiedowns. Four uplift tests performed on a 2.44-m-diameter CMP under different backfill cover, foreslope...

The need to upgrade a large number of understrength bridges in the United States has been well documented in the literature. Through several research projects, which involved testing of strengthening schemes on scale model bridges in the laboratory as well as the testing of strengthening systems on existing bridges, the concept of strengthening sim...

The need to upgrade a large number of under-strength bridges in the United States has been well documented in the literature. Through several Iowa Department of Transportation projects, the concept of strengthening simple-span steel-beam composite concrete-deck bridges by post-tensioning has been developed. The purpose of this paper is to describe...

In response to problems of corrugated metal pipe (CMP) culvert uplift failure caused by unbalanced inlet hydraulic loading, full-scale field testing and numerical analysis were carried out to develop a rational design methodology for CMP inlet tie-downs. This paper describes a series of uplift tests carried out on a 2.44 m diameter CMP under differ...

In this investigation, a testing program was initiated to gain some understanding of the nature of high-density polyethylene (HDPE) as a structural material and as a buried structure. The testing program consisted of a series of parallel plate tests, a sequence of flexural tests, and field tests of buried pipes under varying backfill conditions. Pa...

The objective of this paper is to evaluate the deflection response of polyethylene pipes when loaded near their ends. Tests were conducted on pipes loaded at the center and near their ends to simulate loading of a vehicle at the center of a roadway and on the shoulder. The tests were performed on 900-mm (36-in.) and 1200-mm (48-in) diameter polyeth...

In Iowa there are over 20,000 bridges on the secondary road system. The majority of these bridges are under the jurisdiction of county engineers with limited budgets; therefore many county engineers design and construct their own short-span bridges with their own labor force. The objective of this research is to perform laboratory testing on a brid...

To properly maintain our public infrastructure, civil engineers must learn new methods of inspection technology. Current inspection techniques required for our nation's bridges as well as locks and dams primarily consist of visual and subjective observations. When these inspections indicate that a structural or functional problem may be developing,...

Previous analytical and experimental work by the authors has determined that integrated shell-deck segments can be used to construct short- or medium-span bridges. This system consisted of integrated shell-deck concrete segments that are post-tensioned together to form a simply supported bridge. A 1:3-scale segmental concrete shell bridge model was...

Increases in legal-load limits as well as lack of maintenance has rendered a large number of bridges in the United States deficient and in need of rehabilitation or strengthening. Many of these bridges are classified as deficient because their load-carrying capacity is inadequate for today's traffic. This paper deals with two methods of strengtheni...

Due to lack of maintenance, increase in legal loads, and increased traffic volumes, several thousands of deficient bridges in the surface transportation system needed to be rehabilitated or replaced. One potential solution to several of today's bridge problems is the shell bridge. This system consists of integrated shell-deck concrete segments that...

Corrugated metal pipe (CMP) culverts in some situations have experienced inlet uplift caused by unbalanced pore pressures. Many state departments of transportation (DOTs) have design guidelines for determining the magnitude of force required to restrain CMP against these uplift forces; however, these specified forces vary considerably. Also, the ex...

Corrugated metal pipe (CMP) culverts in some situations have experienced inlet uplift caused by unbalanced pore pressures. Many state departments of transportation (DOTs) have design guidelines for determining the magnitude of force required to restrain CMP against these uplift forces; however, these specified forces vary considerably. Also, the ex...

Each year many prestressed-concrete (P/C) girder bridges are damaged by overheight vehicles or vehicles transporting overheight loads. The effects of this type of loading on P/C bridge behavior was investigated for various types and locations of intermediate diaphragms. The research included a comprehensive literature review; a survey of design age...

Recent surveys of transportation agencies regarding corrugated metal pipe (CMP) culverts have indicated cases of longitudinal flexural failure due to uplift at the inlet. The surveys indicate that inlet tie-down design standards vary by more than 500 percent in the calculated tie-down force required for similar large diameter CMP. In response to th...

Iowa, as well as other states, has experienced several failures of corrugated metal (CMP) culverts, apparently because of inlet flotation. In Iowa, most of these failures have occurred on secondary roads. In a survey of Iowa county engineers, 31 CMP culvert failures occurred within a 5-year period (1983 to 1988). A survey of state departments of tr...

Surveys of county engineers in Iowa revealed that between 1970 and 1975 and between 1983 and 1988 corrugated metal pipe (CMP) uplift failures occurred at a rate of six per year. A similar survey of North American Departments of Transportation (DOTs) revealed only nine failures between 1987 and 1992. All failures involved pipes with diameters greate...

The need for upgrading a large number of understrength and functionally obsolete bridges in the United States has been well documented. The purpose of this project was to investigate two schemes for strengthening the negative-moment regions of continuous composite bridges: (1) Postcompression of stringers; and (2) superimposed trusses attached to s...

The purpose of this first phase of a continuing research program is to examine the potential for strengthening continuous composite bridges by post-tensioning. Testing of a one-third scale bridge model and finite element analysis are used to determine the effects of various straight-tendon posttensioning schemes. Because of both longitudinal and tr...

A finite element model is used to study the behavior of a glued, laminated, longitudinal-deck highway bridge. The bridge, which was developed for short to medium spans, offers a competitive alternative to steel and reinforced concrete in this span range. Experimental tests of a full-scale laboratory test bridge are performed to validate the analyti...

The need to upgrade a large number of understrength and obsolete bridges in the United States has been well documented in the literature. Through several Iowa DOT projects, the concept of strengthening simple-span bridges by post-tensioning has been developed. The purpose of the project described in this paper was to investigate the use of post-ten...

Analytical studies indicated that integrated shell-deck segments can be used to construct short or medium-span emergency bridges. A simply supported bridge with four different shell cross sections was investigated; dead load and various patterns of live loads were considered. The analysis of these shells was performed using the ANSYS general purpos...

This paper briefly reviews the results of NCHRP Project 12-28(4), Methods of Strengthening Existing Highway Bridges. The initial task was a thorough review of international literature to determine strengthening procedures currently being used and to investigate innovative ideas now being considered. The types of structures that show the most need f...

This paper summarizes some of the research and applications related to this strengthening technique. Information relevant to the bonding procedure is provided, including methods for preparing the bonding surfaces and guidelines for adhesive selection and application. Research results pertaining to variations in the plate geometry, the effects of cy...

Post-tensioning can be utilized to increase the flexural strength of beams in single-span, composite steel beam and concrete deck bridges, even when only deficient exterior beams are post-tensioned. Distribution of the axial forces and moments caused by eccentric post-tensioning of the deficient beams must be considered in the design of the strengt...

Streams in western Iowa have been degrading since the turn of the century and this entrenchment has endangered many highway and railroad bridges. Although grade-stabilization structures have been effective in controlling this erosion, the cost of reinforced-concrete stuctures has risen to the point that less expensive materials need to be considere...

The rehabilitation of bridges and other structures is presently receiving considerable attention. The research reported here is a portion of a bridge strengthening project. In the rehabilitation of composite concrete and steel structures, oftentimes inadequate shear connection between the two materials is found. This article presents two methods of...

The use of post-tensioning to increse the strength of steel beams in beam and concrete-slab bridges is shown to be feasible. The study described was conducted to determine a technique for increasing the capacity of the bridges to meet today's loading. The results of testing a half-scale model of an existing bridge indicate that post-tensioning can...

Previous research at Iowa State University has resulted in a shear-bond design equation which was based on data obtained from tests utilizing concentrated line loads on one-way elements. However, since most floor slabs are usually designed for uniformly distributed loads a shear-bond formulation for such loading is required. A modification of the s...

A major bridge problem in the United States is the corrosion of reinforcing steel and the subsequent deterioration of the surrounding concrete due to deicing salts. There have been efforts in the past to alleviate these problems by using reinforcement that will not corrode, including clad steel reinforcement, fiber-reinforced polymer (FRP) reinforc...

Iowa Highway Research Board Project TR-568 was initiated in January 2007 to investigate the use of steel sheet piling as an alternative foundation component for Low Volume Road (LVR) bridges. A total of 14 different sites were initially investigated in several counties as potential candidates for the construction of demonstration projects utilizing...

The problem of an aging and rapidly decaying infrastructure is an issue facing many agencies charged with maintaining a fully functioning transportation system. Numerous bridges of marginal condition must frequently be posted, resulting in detours with increased travel time and distances. However, when tested, these bridges often exhibit strength a...

In June 1996, a series of field-tests were conducted on twin bridges carrying I-680 over county road L34 in Beebeetown, Iowa. The west-bound bridge was damaged by an over-height load. The load fractured a portion of the bottom flange and web of the first two beam lines of the 11-beam structure. A majority of the strands were exposed in the pro-cess...