the magazine of the american concrete pipe association

www.concrete-pipe.orgVolume 58 No. 4 Fall 2006

The Magazine of theAmerican Concrete Pipe Association

American Concrete Pipe Association

Cover:Concrete pipe

under extendedlanes and

overburden upto 20 feet.

This issue:Volume 58, Number 4Fall 2006Concrete Pipe News is published four timeseach year by the American Concrete PipeAssociation. It is designed to provideinformation on the use and installation ofprecast concrete pipe products for a widevariety of applications, including drainageand pollution control systems. Industrytechnology, research and trends are alsoimportant subjects of the publication.Readers include engineers, specifiers, publicworks officials, contractors, suppliers,vendors and members of the AmericanConcrete Pipe Association.American Concrete Pipe Association StaffMatt Childs, P.E.PresidentMichael W. Beacham, P.E.Director of Government RelationsJosh Beakley, P.E.Director of Technical ServicesWanda CochranProject CoordinatorTom Finn, P.E.Western Region EngineerSusan FosterAdministrative AssistantLaHonda HolleAdministrative AssistantKaren HunterDirector of MarketingWendy LambertControllerKim Spahn, E.I.T.,Engineering Services ManagerMedia Task GroupBill Gardner, ChairMadison Concrete Pipe, Inc.Jim BartleySchlüsselbauerTerry DemlerHanson Pipe & PrecastPhillip GaleGeneva Pipe CompanyHeidi HelminkRinker Materials - Concrete Pipe DivisionBill HobsonN C ProductsScott LanderHamilton KentMike LeathersHanson Pipe & PrecastRick PhillipsRinker Materials - Concrete Pipe DivisionRobert PowersInland Pipe LimitedContract Editorial StaffA. Grant LeeAGL Marketing LimitedExecutive EditorGary WilderWilder StudiosProductionPublished by:American Concrete Pipe Association1303 West Walnut Hill Lane, Suite 305Irving, Texas 75038-3008Phone: (972) 506-7216Fax: (972) 506-7682E-mail: [email protected]

Opinions expressed by authors other than staff of the AmericanConcrete Pipe Association do not necessarily reflect the officialpositions or policies of the Association. No part of this publicationmay be reproduced or transmitted by any means without writtenpermission from the publisher.© Copyright 2006 ACPA

EditorialThe Insignificance of a 0.01-inch Crack ...................................................................................... 3The 0.01-inch crack for installed RCP is insignificant when it is determined that the crack is the resultof the concrete and reinforcing steel arriving at the modulus of rupture. Such cracks indicate that theconcrete and reinforcement are working together. Because of the increasing value being placed on theNation’s buried infrastructure, taxpayers have every right to expect engineers, contractors and ownersto work with trained inspectors who are familiar with the procedures involved in the inspection of RCP.

Feature ArticleReinforced Concrete Pipe Jacked through Hard Rock on I-70 ..................................................... 4Over 13,000 feet of reinforced concrete pipe was required for the widening of the Interstate-70 Turnpikein Kansas. All 12-inch to 96-inch diameter crossroad pipe was jacked leaving the flow of traffic on theinterstate undisturbed. Some pipe was replaced with larger sizes because of changes that had occurredover the 50 years since original construction of the highway.

StoriesSignificance of Ultimate-Strength Requirements in Reinforced Concrete Pipe Design ................... 7Unlike most reinforced concrete structures, reinforced concrete sewer and culvert pipes are designed tomeet a specified cracking load, rather than a specified stress level in the reinforcing steel. This is bothreasonable and conservative, since reinforced concrete pipe is tested in-plant in accordance with theAmerican Society for Testing and Materials (ASTM) specifications.

Concrete Box and Pipe Storm Sewers Alleviate Massive Flooding Problem ............................... 10The City of Wichita installed a precast concrete box culvert for almost two miles from a flood-pronearea of the city to the Arkansas River. Precast concrete boxes were used because of the consistency ofthe product and the speed of installation. The contract called for sizes ranging from 8-foot x 5-foot to10-foot x 5-foot, including over 1,500 feet of concrete pipe, and numerous inlets.

Thinking Long Term in Genesee County ...................................................................................... 12The Michigan Supreme Court ruled that the Genesee County Drain Commissioner could charge a fee forall new direct and indirect connections to new sewerage. This funding tool ensured that propertyowners of new construction would pay for increased capacity in the County’s sewer system. This actionprovided funding for construction of the Northeast and West Trunk Relief Sewers to handle sewageoverflow. Over six miles of reinforced concrete pipe in a variety of diameters was used in the two reliefsewers.

Evaluation of HDPE Pipe Performance on Kentucky DOT and Ohio DOT Construction Projects ...... 16In May 2005, the Kentucky Department of Transportation (KYDOT) formed a task group to evaluatecurrent specifications and the use of HDPE pipe on future KYDOT projects. KYDOT selected sevenHDPE sites and ODOT selected eleven. Pipeline and Drainage Consultants performed the fieldevaluations in the summer and fall of 2005.

Photo: Miller the Driller

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CONCRETE PIPE NEWS www.concrete-pipe.org FALL 2006

contents

Kim Spahn, E.I.T.Engineering Services ManagerAmerican Concrete Pipe Association

The Insignificance ofa 0.01-inch Crack

“Some engineers insist that a crack in aconcrete pipe in excess of 0.01 inch representsa failure or partial failure situation. Such aconclusion is utterly ridiculous and representsa disservice, not only to the concrete pipe in-dustry, but taxpayers as well.” This quote fromProfessor M.G. Spangler, a well-respected au-thority and early pioneer in the design of con-crete pipe, should be taken into considerationwhen designing, installing, inspecting, orfunding a project using reinforced concretepipe (RCP). All parties involved should beaware of the insignificance of a 0.01-inchcrack.

Reinforced concrete pipe, like other rein-forced concrete structures, is designed tocrack. It is well known that while concrete isvery strong in compression, its tensile strengthis so low that it is considered negligible indesign. RCP performance is dependent upon

the high compressive strength of concrete andthe high tensile strength of steel. As load onthe pipe increases, and the tensile strength ofthe concrete is exceeded, micro-cracks willform first at the invert and occasionally at thecrown as the tensile load is transferred to thesteel. This moment is known as the modulusof rupture. Because of the excellent distribu-tion of tensile stresses in RCP, cracks are verysmall. Typically, cracks form a V-shape withthe largest part of the crack at the surface.Cracks most often terminate before reachingthe reinforcement. The presence of a 0.01-inch crack does not represent failure, butrather an indication that the concrete and re-inforcement are working together as intended.

The 0.01-inch crack criterion has beenused as a service load design requirement forRCP for nearly 70 years. This criterion hasserved the industry well through the designa-tion of a plant test that it must meet. It hasalso served the public well by conservativelyensuring that a strong and durable product isused in buried concrete infrastructure. MostRCP is designed to have a crack width of 0.01inch or less, after the fully installed loadingcondition is experienced. While a crack widthgreater than 0.01 inch is an indication thatthe performance of the soil-pipe structure isnot entirely consistent with its original de-sign, it is not necessarily an indication thatthe specifier should be overly concerned withthe performance of the installed pipe.

The AASHTO LRFD Bridge ConstructionSpecification, Section C27.6.4 states, “Gener-ally, in non-corrosive environments (pH ≥ 5.5)cracks 0.10 inch or less in width are consid-ered acceptable.” This allows for 10 timesgreater width than the design crack withoutrepair. AASHTO LRFD Bridge ConstructionSpecification, Section C27 goes on to say thatin other environments, “Cracks having widthsequal to or greater than 0.01 inch and deter-mined to be detrimental shall be sealed by a

Continued on Page 15

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FALL 2006 www.concrete-pipe.org CONCRETE PIPE NEWS

editorial

More than 30 million vehicles each yearare carried on the Kansas Turnpike from Kan-sas City to just north of the Oklahoma bor-der, south of Wichita. Traffic on the turnpikewas increasing at an average of three percentper year from 1995 to 2001, according to theKansas Turnpike Authority (KTA). BetweenEast Topeka (Toll Plaza 183) and Lecompton(Toll Plaza 197), traffic volume was increas-ing by five percent per year, due to commutertraffic between Lawrence and Topeka. In 2001and 2002, studies conducted on behalf of theKansas Department of Transportation (KDOT)and Kansas Turnpike Authority by HDR En-gineering, Inc., and HNTB Corporation, pro-vided the KTA with information to supportthe decision to widen this stretch of I-70 tosix lanes to accommodate the volume.

With that kind of traffic volume and no

REINFORCED CONCRETE PIPEJACKEDTHROUGHHARDROCKON I-70

suitable alternate route, KTA had to find away to complete the road-widening projectwithout stopping traffic. The Kansas Citybased design team at HNTB Corporation (En-gineers, Architects, Planners), proposed thatall crossroad pipes would be jacked under I-70 leaving the flow of traffic on the interstateundisturbed. After the decision by KTA to jackthe cross drains, reinforced concrete pipe(RCP) became the only feasible choice be-cause of the inherent strength of concrete.KTA’s plans for improving I-70 included wid-ening the route to six lanes and reconstruct-ing the highway from the ground up.

The contractor on the project was N.R.Hamm Contractor, Inc. of Perry, Kansas whofocused on maintaining traffic flow through-out the bid process, and supported the jack-ing pipe option. Hamm chose Miller the Drillerof Des Moines, Iowa to assist with the pipejacking, and Cretex Concrete Products Mid-west of Bonner Springs, Kansas to supply the

By Edward A. Sexe, P.E., Market ManagerCretex Concrete Products Midwest, Inc.913-422-3634

REINFORCED CONCRETE PIPEJACKEDTHROUGHHARDROCKON I-70

Feature Story

Photo: Miller the Driller

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concrete pipe. Careful construction coordi-nation was required between the concretepipe supplier, road-building contractor andthe pipe-jacking contractor. While the pipejacking was taking place at several locationsalong the alignment of the road widening,Hamm Construction began placing fill overruns of concrete pipe that connected to thejacking pipe where it exited the existing roadbase. The new lanes were being constructed,as the jacking program was being completed.

Reinforced concrete pipe was best suitedfor the drainage systems at the base of thenew lanes, because the installation was apositive projecting embankment with over-burden up to 20 feet deep. Concrete pipeculverts could accommodate the earth loads,design life of the existing and new lanes andconnection to the jacking pipe to provide acontinuous concrete drainage struc-ture.

Aside from carrying out precisionjacking operations and properly em-bedding runs of concrete pipe underthe new lanes on either side of theexisting lanes, Hamm Constructionwas faced with widening the road insome areas where the highway passedby rock ledges. Any blasting had tooccur without stopping traffic andcarefully coordinated with KansasHighway Patrol (KHP).

Whenever rock ledge blasting wasrequired, Hamm scheduled the blast-ing between 10:00 a.m. and 11:00 a.m.when traffic was at a minimum. Thedecision to not blast at night was be-cause of the risk of missing debrisduring the cleanup of the highway.The KTA, KHP and Hamm developeda procedure to accommodate theblasts. First, a turnpike maintenancetruck would find a break in the trafficand merge behind the leading pack of ve-hicles to be sure that no one stopped on ashoulder or slowed down. Then, two high-way patrol officers would enter the traffic,immediately behind the turnpike personnel,

driving side by side at about 40 miles perhour to slow the traffic creating an ever-wid-ening gap between the leading cars, mainte-nance truck and the vehicles behind the high-way patrol.

While traffic traveled along the highwayat a controlled speed, Hamm set off their blastcharges within the gap created by the controlvehicles and scrambled to clear the resultingdebris. All of this action took place withoutstopping the flow of traffic. Hamm had be-tween two and four minutes to blast and clearthe highway before the patrol cars led thetraveling public onto the stretch of highwaythat was affected.

RCP was jacked into place at every valleyalong the route using diameters ranging from12 inches to 96 inches. Some pipe was re-placed with larger sizes because of changes

to the drainage areas and imperviousness ofthe drainage area that had occurred over the50 years since original construction. Many ofthe existing crossroad culverts were bitumi-nous-coated galvanized steel pipe and struc-

Large diameter RCP accommodated changes in volume of runoffover past 50 years and imperviousness of the drainage area.

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Feature StoryFeature Story

Project: I-70 Kansas Turnpike Widening ProjectEast Topeka (M.P. 184) to Lecomption(M.P. 197)

Owner: Kansas Turnpike AuthorityWichita, Kansas

ProjectDesign: HNTB Corporation (Engineers,

Architects, Planners)Kansas City, Missouri

Contractor: N.R. Hamm Contractor, Inc.Perry, Kansas

TrenchlessTechnologyContractor: Miller the Driller

Des Moines, Iowa

Quantities: Approximately 13,000 feet of RCP forjacking and positive embankmentinstallation ranging in size from 12inches to 96 inches in diameter for thesection between East Topeka andLecompton.

122 flared end sections.

Producer: Cretex Concrete Products MidwestBonner Springs, Kansas

Cretex Concrete Products Midwest is an affiliatecompany of Cretex Companies, Inc. Cretex Concretecompanies continue to produce reinforced concretepipe and other precast and prestressed concreteproducts to fulfill the infrastructure needs of the centralUnited States. The Cretex Concrete Products Midwestfacility was built in 1997 to improve service in theKansas and Missouri market areas. In addition to pipe,a full range of precast box sections and the CretexArch Bridge System are produced at this facility. Cretexwas founded in 1917 in Elk River, Minnesota, thecurrent site of the company’s corporate headquarters.See www.cretexinc.com for more information and alisting of their facilities.

tural steel plate pipes that were installed in1956. According to the KTA the existing cul-vert pipes were at the end of their servicelife. These cross drains were blocked on thedown stream side and filled upstream withcementitious flowable fill (a mixture of fly ash,borax, and water). Filling the void created bythe abandoned pipe would eliminate the pos-sibility of collapse and ultimately a pavementfailure.

Jacking and boring reinforced concretepipe is not a procedure that any utility con-tractor or excavation contractor can under-take. Miller the Driller has been a pioneer inthe jacking and tunneling industry since it wasestablished in 1948. One of the biggest prob-lems encountered during pipe jacking opera-tions was the presence of solid limestone inmany locations along the length of the project.An 18-foot push through hard rock was com-mon and considered a good day of jacking.

Unlike explosive charges used to blastthrough rock cuts to make room for addi-tional lanes, the blasting device used in tun-neling is about the size of a shotgun shell. Itis designed to crack the rock so that it can beremoved. This kind of blasting was appliedin the jacking process and did not interferewith the movement of traffic.

It is common for designers and specifiersto think that jacked pipe should be of a higherclass than pipe installed in an open trench. Ahigher-class pipe is not always the appropri-ate choice. Jacking puts pressure on the endof the pipe. Increasing the class of the pipeincreases its ability to act like a beam. SomeRCP producers supply standard inventory pipefor jacking jobs, while others make projectspecific pipe with a thicker wall, simply togive the jacking contractor a broader “shoul-der” of pipe on which to push. For the I-70widening, Cretex chose to use a pipe with athicker wall than its standard pipe.

Over 13,000 feet (2.5 miles) of reinforcedconcrete pipe, along with 122 flared end sec-tions were required for the project. The wid-ening began in the spring of 2005 and isscheduled to be finished in May 2007. A total

of 9,736 feet (1.8 miles) of RCP was jackedunder the highway completing a system of86 crossroad culverts. The jacking and tun-neling work took 10-1/2 months to complete.The cost of the project between East Topekaand Lecompton is $54 million.

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Feature StoryFeature Story

Unlike most reinforced concrete struc-tures, reinforced concrete sewer and culvertpipes are designed to meet a specified crack-ing load, rather than a specified stress levelin the reinforc-ing steel. Thisis both reason-able and con-s e r v a t i v e ,since rein-forced con-crete pipe istested in-plantin accordancewith AmericanSociety forTesting andM a t e r i a l s(ASTM) speci-fications.

Pipe Performance TestThe first visible crack observed in a three-

edge bearing (TEB) test was the acceptedcriterion for pipe performance when the in-dustry first began to establish performancetests for pipe. The observation of such cracks

was subject to variations depending upon theenthusiasm, diligence and eyesight quality ofthe observer. It became apparent that therewas a need for a criterion based on the mea-surable crack of a specified width. Professor

W.J. Schlick of Iowa State University estab-lished the 0.01 -inch crack width using a 0.01-inch thick leaf gauge to provide a measurableand definitive crack size for the three-edgebearing test. Eventually, the 0.01-inch (0.25mm) crack became the accepted criterion forpipe performance.

The design crack is V-shaped in nature and

Significance ofUltimate-StrengthRequirements inReinforcedConcrete PipeDesign By Balaram K. Singh, P.E.

Michigan Department ofTransportation

Concrete sewer and culvertpipes are designed to meeta specific cracking load.

Photo: ACPA photo library

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is widest at the surface penetrating usuallyno further than the first reinforcing cage in thepipe. Corrosion of the reinforcement is unlikely,providing the crack is not wide enough to per-mit circulation of moisture and replenishmentof oxygen. Cracks in excess of 0.01-inch (0.25mm) have been observed after several yearswith no evidence of corrosion.

Reinforced concrete pipe is designed tocrack. Cracking under load indicates that thetensile stresses have been transferred to thereinforcing steel. A 0.01-inch (0.25 mm) widecrack in a concrete pipe does not indicatestructural distress and such pipe will performas intended in the installed condition. Pipeproduced with greater than one inch (25 mm)cover over the reinforcing steel is an excep-tion. In these designs, acceptable crack widthshould be increased in proportion to the ad-ditional concrete cover.

Load Carrying CapacityThe strength of RCP is stated as D-load,

which is the load in pounds per lineal foot perfoot of internal diameter. The strength test re-quirements under the TEB method are classi-fied according to the D-load that produces a0.01-inch (0.25 mm) crack and the D-load thatproduces the ultimate load.

When concrete pipe is subjected to exter-nal loading, resisting stresses induced in thepipe wall are flexural, axial and diagonal ten-sion. Tensile stresses are developed in the in-side wall, at the crown and invert, and on theoutside at the springline. Compressivestresses are developed in the walls oppositethe tensile stresses. The reinforcing of a con-crete pipe consists of the placement of steelreinforcement in those zones of the pipe wallwhere tension stresses exist. Reinforcementin the pipe wall where compression stressesexist is not required, but is used in variousmethods of reinforcing for ease of placement.Stirrups placed radially within the pipe wall at

the crown and the invert zones resist the in-herent diagonal shear and radial tensionstresses produced by the external loading ofthe pipe.

Indirect DesignIn the indirect method, pipe is designed

for a concentrated test load that is determinedby the relationship of field-calculated momentto the TEB test moment for the same load. Thisrelationship is called bedding factor which isdetermined by dividing the bending momentobtained in a TEB test by the controlling bend-ing moment in the field. Many pipes, particu-larly large diameter and high strength classessuch as Class IV and V, have their strengthgoverned by shear in TEB tests, while theirfield strength may be governed by both shearand flexure.

The indirect design method for concretepipe is similar to the common working stressmethod of steel design, which employs a fac-tor of safety between yield stress and the de-sired working stress. The factor of safety isdefined as the relationship between the ulti-mate strength D-load and the 0.01-inch (0.25mm) crack D-load. The 0.01-inch (0.25 mm)crack D-load is the maximum TEB test loadsupported by a concrete pipe before a crackoccurs having a width of 0.01-inch (0.25 mm)measured at close intervals, throughout alength of at least one foot (300 mm). The ulti-mate strength D-load is the maximum TEB testload supported by a pipe.

Direct DesignDirect design is used specifically for the

field condition anticipated loads and the re-sulting moments, thrust and shear caused bysuch loadings. Standard installation directdesign (SIDD) emphasizes minimizing com-paction immediately below the invert regionto the extent feasible with uniform longitudi-nal support, and maximizing soil quality and

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compaction level in the outer portions of thehaunch zones below the pipe. A modified soilspressure configuration called the Heger dis-tribution has been developed as a function ofsoil type and compaction. The configurationsare referred to as Type 1, Type 2, Type 3 andType 4, depending upon pipe bedding, soiltype and compaction level. The difficulty inobtaining specified soil compaction under thehaunches of the pipe has been recognized inthe soil pressure distribution by conservativelyassuming all installations will have voids andsoft inclusion in the haunch area.

The SIDD procedure facilitates the use ofa variety of design options for minimizing theamount of reinforcing steel to suit the needsof a specific installation. The outer cage rein-forcement is designed to meet specific de-sign conditions in contrast to the designsgiven in ASTM C76 requiring outer reinforce-ment to be 0.6 times of the inner reinforce-ment area, regardless of the governing de-sign criteria for inner reinforcement. The de-sign area of the inner reinforcement is some-times increased to provide increased shearor 0.01-inch (0.25 mm) crack strength, butthese criteria usually do not govern the outerreinforcing design. The outer reinforcementarea, therefore, frequently can be less than0.6 times the inner reinforcement area.

A rational method is provided for determin-ing when shear or radial tension reinforcementis required and for designing stirrup reinforce-ment to meet these strength criteria. The di-rect design procedure permits more accuratedesign of reinforced concrete pipe and evalu-ation of pipe structure behavior using proce-dures that are similar to those used for otherreinforced concrete structures.

Comparing Indirect and DirectDesign

In comparing indirect design (D-load) withdirect design, the maximum moment and

Note: A longer version of this article, authored byB.K. Singh, was first published in the summer 2006issue of Concrete Engineering International(www.concreteengineering.com)

shear in the TEB test is at the same locationon the pipe, which is not the case in the field.Considering the concentrated load and reac-tion that exists in the indirect design test, fail-ure modes can exist that are not typical forthe direct design pipe, which often requirespecial steel reinforcing assemblies that areunnecessary in the field.

The ultimate strength of concrete pipe inthe buried condition is dependent on varyingsoil bedding factors and installation types. Theultimate strength may amount to varying fail-ure modes and shall not necessarily have arelationship to the ultimate strength, as deter-mined under TEB conditions.

Pipe design methodologies allow publicowners of infrastructure, pipe producers andcontractors to leverage their strengths. Pub-lic owners may minimize a project’s overallexpense by balancing the cost of the pipe withdifferent allowable combinations of beddingand types of installation. A producer may sup-ply product with the appropriate reinforcingfor the buried application instead of pipe pro-duced to meet empirical testing criteria. Acontractor may reduce installation costs byselecting bedding conditions, installation typeor pipe strengths, which permit a fast installa-tion with fewer installers. If an owner and con-tractor know the quality of the soil and instal-lation procedures, pipe strengths can bemodified accordingly when unstable soils areencountered, or high quality in-situ soil con-ditions exist.

Understanding the significance of ultimate-strength requirements in reinforced concretepipe design leads to better design and long-term performance of storm and sanitary sew-ers.

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Photos: M&W Concrete Pipe & Supply Company

Wichita, the largest city in Kansas with apopulation of over one-quarter million, expe-riences occasional flash flooding from the Ar-kansas River, which passes through the city. Inaddition to the flooding caused by the river, asection of Midwest Wichita has a history offlooding from a time long before paved roadswere introduced in the 1950s. One of the hard-est hit areas is the neighborhood east of WestStreet between Douglas and 2nd Streets, run-ning west from the Arkansas River. Here, muchof the flooding was attributed to undersizedstorm sewers that no longer had the capacityto accommodate the volume of runoff from thenorth and west. During heavy rainfall events,the north-south running West Street had to beclosed to traffic, since a continuous half mileof the street was often underwater. The stormwater drainage problem had to be solved be-fore the City could reconstruct West Street.

In 1993, Wichita introduced the EquivalentResidential Unit (ERU), which is a monthly feepaid by the owners of all properties in the Cityto support the efforts of the Public Works De-partment. The Public Works Department is re-sponsible for the construction, reconstructionand maintenance of the City’s storm water drain-age system, as well as the water quality aspectsof the City’s storm water pollution preventionprogram. The 1st and 2nd Street Drainage Im-provement Project was funded from the ERUprogram.

Beginning at the most severe flood-prone

Concrete Box andPipe Storm SewersAlleviate MassiveFlooding Problem

section of West Street, this project routed a pre-cast concrete box culvert for almost two milesto a discharge point in the Arkansas River. Pre-cast concrete box culvert construction was se-lected because of the consistency of the prod-uct and the speed of installation. The contractcalled for box sizes ranging from 8-foot x 5-foot to 10-foot x 5-foot, including over 1,500feet of pipe and numerous inlets. A secondary60-inch diameter precast concrete pipe trunkline was responsible for relieving the long-stand-ing 2nd Street and Sheridan Street flooding prob-lems. Inlets were placed at low points, and pipestubs were incorporated in the line to accom-modate future connections.

Unlike projects where there are lengths ofprecast pipe and related precast componentsand sections that are cast-in-place, this job wasdesigned as a total precast concrete storm sewerstructure. Behind the speed of the installation

Photos: Jeff Bradley, Baughman Company

By Jarrold F. Bradley, Jr.City of Wichita

Flooding attributed to undersized storm sewers.

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were close to 200 hours of engineer-ing from the staff at McPherson Con-crete Products and its affiliate, WichitaConcrete Pipe. Both plants suppliedpipe, structures, and boxes. WhileWichita supplied the bulk of the stan-dard products, McPherson supplied themajority of the specials. Project challengesrelated to existing utilities in the right-of-way and box geometry required the pro-duction of many special transition pieces.

At the beginning and throughout theproject, the design team of Baughman Com-pany, P.A. and Ruggles & Bohm, P.A. workedclosely with City engineers and the contrac-tor, Wildcat Construction, to size the boxesand special transition structures, set limits tothe work area, establish clearances and eventhe production rates of the product suppliers.While construction primarily took place in theexisting street right-of-way, instructions weregiven to the contractor regarding the amountof traffic that was allowed to be rerouted fromthe site at any time. Extensive sewer relocationplans were required, along with utility reloca-tions and complete pavement replacementalong the reconstruction route. The contractoraccommodated the concerns of residents, es-pecially those with special needs. Restorationwork included Americans with Disabilities Act(ADA) compliant sidewalk ramps and completestreet reconstruction. In most cases, restorationimprovements in the eyes of residents surpassed

McPherson Concrete Products, Inc. and WichitaConcrete Pipe, Inc. provide a complete range of precastconcrete products for storm water and sanitary sewersincluding concrete pipe, box sections, manholes, catchbasins and inlets. Both companies are affiliated toprovide products to clients throughout the region. Forinformation, see www.mcphersonconcrete.com.

Project: The 1st and 2nd Street DrainageImprovement ProjectWichita, Kansas

Owner: City of WichitaProjectDesign: Baughman Company, P.A.

Wichita, KansasRuggles & Bohm, P.A.Wichita, KansasCity of WichitaPublic Works Department

Contractor: Wildcat ConstructionWichita, Kansas

Quantities: Approximately 2 miles of 8-foot x 5-footand 10-foot x 5-foot precast concretebox sections1,500 feet of concrete pipe, including60-inch diameter RCP.Numerous precast concrete inlets

Producers: McPherson Concrete Products, Inc.McPherson, KansasWichita Concrete Pipe, Inc.Wichita, Kansas

the streetscape conditions that predated con-struction.

The 1st and 2nd Street Drainage ImprovementProject was completed in November 2005 al-most seven months ahead of schedule and ap-proximately $1.4 million below the City’s esti-mate of $6 million. Wildcat Construction wasallowed until July 2006 to complete this project,but reconstruction was completed early becauseof the use of precast products, comprehensivedesign details, and a strong cooperative atti-tude between all parties. Along with the speedycompletion and teamwork, this project was sig-nificant because it provided the first major drain-age trunk storm sewer from the Arkansas Riverto serve a flood prone area that has beleagueredthe citizens of Wichita for over 35 years.

The contract called for precast concrete boxes rangingin size from 8-foot x 5-foot to 10-foot x 5-foot.

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Big projects often require special tools andstrong-willed professionals to make them a re-ality. This is a story about how a local leaderwas able to secure long-term funding for theconstruction and maintenance of sanitary andstorm sewers in a high growth county in Michi-gan, and the application of reinforced concretepipe for maximum return on investment. Oncefunding was secured, the money was used toconstruct major trunk relief sewers that willreturn great savings to the county by adding toits assets’ net worth in terms of low mainte-nance and performance for generations.

In the late 1990s, Genesee County (south-east Michigan) ran out of sewer capacity in itssanitary sewer interceptors. To relieve this situ-ation, phased improvements were required tothe Northeast and West Trunk Relief Sewers tohandle sewage overflow. The Northeast ReliefSewer is to relieve flow from the northeastportion of Genesee County including the town-ships of Flushing, Mt. Morris, Genesee, Davisonand the City of Burton. The West Trunk ReliefSewer is to alleviate flows from the Grand BlancTownship-City Interceptor, by diverting sew-age into the Swartz Creek Interceptor locatedto the west. The project will free up capacityand reduce sanitary sewer overflows and back-ups.

When all construction phases are completed,Genesee County will be able to process anadditional 31,600,000 gallons of sewage per dayto meet sewage treatment needs for the next30 years. The relief sewers eliminate 20 majorpump stations and their maintenance costs.Since Interstate 69, Interstate 75 and Highway23 merge in Genesee County, increased sewer

capacity will ensure that the county remains ahub of commerce by providing infrastructurecapacity, protection of public health and theenvironment, and provision of services for eco-nomic development.

Jeff Wright, the Genesee County Drain Com-missioner led the drive to find a means for long-tem funding of the relief sewers and other majorsewer projects. State law provides for the elec-tion of the Drain Commissioner, responsible forthe administration of the Drain Code, 1956, asamended, every four years on a partisan basis.Duties include the construction and mainte-nance of drains, determining drainage districts,apportioning costs of drains among propertyowners, and overseeing local units of govern-ment that receive bids and award contracts fordrain construction. The Drain Commissioner,by action of the County Board of Commission-ers, serves as the County Agency that providessanitary sewer collection and treatment for 32local municipalities covering six counties. Thisresponsibility covers more than 680 squaremiles, over 180,000 residents and thousands ofbusinesses and their employees.

Mr. Wright was well aware of the need forrelief sewers when elected in 2001, since hewas born and raised in Genesee County andhad worked for previous drain commissionersin various capacities from 1974 through 1997.His predecessor wanted to raise sewer rates tofund relief projects. In a move that took a rul-ing by the Michigan Supreme Court to prevail,Jeff Wright implemented the County CapitalImprovement Fee, (CCIF) which authorized theCounty Drain Commissioner to charge a CCIFto all new direct and indirect connections for

By Robin Woodbury,Director of MarketingPremarc Corporation616-437-0781

Photos: David Dicks, Premarc Corporation

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$1,000.00 per connection. This funding toolensured that property owners of new construc-tion would pay for increased capacity in theCounty’s sewer system, not existing customers.By summer 2006, the CCIF had collected ap-proximately $13 million. This source of fundsalong with revenue bonds enabled the Countyto spend $90 million on sewer improvementswithout raising sewer rates.

Over 300 property easements were neededfor the sewer improvements. Historically,Genesee County paid $1 for property ease-ments. With revenue procured by the CCIF, theCounty was able to compensate property own-ers at fair market value, preventing the con-demning of properties for the easements. Landacquisitions were less than half of one percentof the total project costs.

The Northeast Relief Sewer was designedin four phases that included approximately32,000 feet of 48-inch to 72-inch diameter rein-forced concrete pipe (RCP), 14,000 feet of 48-inch diameter RCP and 2,500 feet of 30-inch to42-inch diameter RCP. Approximately 8,000 feetof the 48-inch diameter RCP interceptor wasconstructed using micro-tunneling techniques.These new sewers eliminate three major andseveral smaller pump stations, while redirect-ing several existing interceptors into the newsystem, thereby relieving the existing over-loaded system of approximately 28 million gal-lons per day (peak flow).

Consoer, Townsend, Envirodyne Engineers,Inc. (CTE) was the lead engineer on the project.As one of several AECOM companies, CTE ispart of a global design and management orga-nization with 24,000 employees worldwide. In2005, AECOM was featured prominently in the“Top 500 Design Firms” of Engineering NewsRecord, ranking first in transportation, sewer/waste, and general building, and third overall.Hubbel, Roth and Clark assisted with pump sta-tion design while Wade Trim, Inc. and RoweInc. assisted with surveying and layout of theproject.

Phase 1 was completed in 2005 at a cost of$9 million. Phase 2 was awarded to Zito Con-struction in 2005 and work began that winter.Incorporated in 1969, Zito Construction is a

family owned company with 45 employeesspecializing in road building, earth moving,sewers and watermains for municipalities andMichigan developers. Burial depths of the RCPranged from twenty to thirty feet. High watertables were encountered through 70 percentof the project, presenting additional challengesfor the Zito crew. When construction is com-pleted on Phase 2 by winter 2006, over 18,072feet of 72-inch diameter RCP will have beeninstalled at a cost of $8.5 million.

Phase 3 has been awarded to D’AlessandroContracting Group, located in Detroit. Thisphase will require the installation of two milesof 48-inch through 54-inch diameter RCP. Fifty-foot burial depths will require tunneling of aportion of this $7.5 million project. Construc-tion will begin in fall, 2006.

Phase 4 will include the installation of fivemiles of 48-inch through 72-inch diameter RCP.

While work has been on-going on the North-east Extension, work is being completed onthe West Trunk Interceptor. CTE was the leadengineer for Phase 1 of the West Trunk Inter-ceptor, and Wilcox Engineeringwas the lead design engineerfor Phases 2 through 4. Whencompleted, the interceptor willinclude approximately 12 milesof new sewer. Phase 1 and 2were completed in 2004 and2005. Phase 3, awarded toD’Agostini & Sons, Inc beganconstruction in mid July of2006.

D’Agostini & Sons, Inc. is afamily-owned business with140 employees specializing inheavy construction, tunneling,sewers, watermains and emer-gency infrastructure repair, in-corporated in 1967. When theproject is completed by Novem-ber 1, 2006, they will have in-stalled over 12,408 feet of 21-inch diameter RCP. The fourthphase of the West Trunk willbid in the spring of 2007.

Superior joints, competitive

Buried depths forRCP ranged from 20to 30 feet in open cutmethod.

13


prices, and the ability to provide on-time deliv-eries prompted Zito Construction, D’AlessandroContracting Group and D’Agostini & Sons, Inc.to choose the Premarc Corporation of Durand,Michigan to supply reinforced concrete pipefor certain sections of their contracts. A majorconcern was the assurance of a watertight jointfor all pipe units to limit migration of fine soil.Storm water inflow and groundwater infiltra-tion had added to the sanitary flows that ex-ceeded the capacities of these interceptors. Byusing diamond-tipped grinding wheels, Premarcproduces exact dimensional tolerances duringthe manufacturing of the gasket-seating surface,ensuring dimensional control over the pipejoint. Construction crews are able to accuratelyinstall gaskets and home the pipe.

Premarc worked with engineers of theGenesee County Drain office to ensure Phase3 concrete pipe of the West Trunk was installedaccording to ASTM C-1479. This involved chang-ing the backfill specification from an open-graded aggregate material, which allowed soilmigration and perhaps shifting and movementof the pipe, to a Class 2 sand backfill. Thischange ensured that the pipe would last wellbeyond the design life of the project.

To solve the problem of capacity in theexisting sewers of Genesee County, it requiredinnovative project funding and products thatwould meet the expectations of a life cycle costanalysis. Both the Northeast and West TrunkRelief Sewers are being constructed within the

Project: Genesee County Northeast and WestTrunk Relief Sewers

Owner: Genesee County Drain Commissioner

Designers: Consoer, Townsend, EnvirodyneEngineers, Inc.Flint, MI

Wilcox EngineeringLansing, Michigan

Contractors: Zito Construction Co.Grand Blanc, Michigan

D’Agostini & Sons, Inc.Detroit, Michigan

D’Alessandro Contracting GroupDetroit, Michigan

Quantities: 13,080 feet of 72-inch diameterClass IV RCP (supplied by 4,992 feet of72-inch diameter Class V RCP Premarc)1,064 feet of 24-inch diameterClass III RCP12,408 feet of 21-inch diameterClass IV RCP376 feet of 12-inch diameterClass IV RCP23 (48-inch diameter) manholes10 (60-inch diameter) manholes

The Premarc Corporation is Michigan’s largest precastconcrete pipe manufacturer. Founded in 1927 inDurand, Michigan by the Marsh family, the companyfirst operated in the Flint and Lansing area but nowhas facilities in Cadillac, Grand Rapids and Clarkston,as well as Durand. Premarc’s delivery fleet suppliesthe entire lower peninsula of Michigan and extendsinto Indiana. Products include precast reinforcedconcrete sanitary and storm sewer pipe, manholes,catch basins, wet wells, and pump stations. Bridgeproducts include concrete boxes, and prestressedbridge beams. For more information, seewww.premarc.com.

model of long-term planning for service andmaintenance. Taxpayers, both new and estab-lished will benefit from the return on invest-ment enabled by the CCIF and reinforced con-crete pipe.

Reinforced concrete pipe ranged in size from 12 to92 inches in diameter.

14


method approved by the engineer.” Thismeans that it must first be determined thatthe crack will have a damaging or harmfuleffect, and even then it only requires a repairseal, not replacement. For destructive reac-tions to occur within a crack located in a cor-rosive or highly alkaline environment, theremust be a continuous replenishment of theaggressive solution and/or oxygen.

Many sources agree the 0.01-inch crackwas never intended to determine the failureof installed RCP. Professor W.J. Schlick of IowaState University established this crack widthto determine the strength of RCP in a three-edge-bearing test. He used a 0.01-inch thickleaf gauge to provide a measurable and de-finitive crack size for the test. The three-edge-bearing test applies a bearing strip along thetop of the pipe, and two closely spaced bear-ing strips along the bottom. This test createsa much more severe load than installed pipeconditions. Specifications for RCP require anultimate load resistance that exceeds the re-quired 0.01-inch crack strength, giving thedesigned pipe a significant factor of safetyabove the required service load. The 0.01-inch crack width is not related to the size of acrack that should be considered a structuralfailure of an installed concrete pipe. ASTMC76-06 states in section 11.3.1, “Pipe that havebeen tested only to the formation of a 0.01-inch crack and meet the 0.01-inch load re-quirement shall be accepted for use.”

A process, known as autogenous healingoften occurs between two surfaces of narrowcracks in buried pipe. Autogenous healing isthe ability of concrete to heal itself in the pres-ence of moisture. This explains why the heal-ing occurs in concrete pipe where water con-ditions are higher than that of other concretestructures. During this process calcium car-bonate, a hard white substance, forms whenmoisture reacts with unhydrated cement pow-

der and regenerates the curing process. Thisself-healing process creates a monolithic struc-ture just as if the crack had never occurred.In Ohio, the Department of Transportationhas developed a post-construction inspectionstandard for installed pipe, where there is evi-dence of cracking that requires nothing bedone to a pipe with a crack width up to 0.06inch, due to the autogenous healing that isexpected to occur.

With recent developments in video imag-ery technology, OSHA confined space rules,and GASB 34 asset management rules, videoinspections are often employed to inventoryexisting systems and for the acceptance ofnew installations. During these inspections,cracks and the presence of autogenous heal-ing may be evident. All too often, an untrainedeye views a small crack in a post installationvideo inspection of a RCP and the crack isdetermined to be a failure. This may occurbecause some cameras currently available forvideo inspections produce distortion, andmagnify hairline and shrinkage cracks. Thiscauses cracks to appear much larger, result-ing in unnecessary repairs or replacements.Recent advancements in video inspectiontechnology have produced calibration devicesthat clearly indicate the actual size of the crack,resulting in an accurate inspection. Hairlinecracks are expected to occur in concrete pipe,so the reinforcing steel will perform as in-tended.

The 0.01-inch crack in installed RCP is in-significant when determined that the crack isthe result of the concrete and reinforcing steelarriving at the modulus of rupture. Such cracksindicate that the concrete and reinforcementare working together. Because of the increas-ing value being placed on the Nation’s bur-ied infrastructure, taxpayers have every rightto expect engineers, contractors and ownersto work with trained inspectors who are fa-miliar with the procedures involved in theinspection of RCP.

editoralcontinued from page 2

15


American Concrete Pipe Association1303 West Walnut Hill Lane, Suite 305

Irving, TX 75038-3008

www.concrete-pipe.org

By Pipeline and Drainage Consultants (a subsidiary of SpartanConstruction)Burlington, Kentucky

PRESORTEDSTANDARD

US POSTAGE PAIDDALLAS, TX

PERMIT NO 1883

In May 2005, the Kentucky Department of Transportation (KYDOT)formed a task group to evaluate current specifications and the use ofHDPE pipe on future KYDOT projects. It was decided to evaluate thelong-term performance on previous HDPE pipe installations beforeproceeding further. The Ohio DOT (ODOT) initiated a similar perfor-mance evaluation in the fall 2005, to review previously installed HDPEpipe sites. KYDOT selected seven HDPE sites to be evaluated andODOT selected eleven.

Pipeline and Drainage Consultants performed the field evalua-tions in the summer and fall, 2005. Several of these pipelines hadbeen reviewed previously for long-term performance with results pub-lished in Condition Investigation of HDPE pipe in service in the UnitedStates (six states), January 24 2002 by Wiss, Janney Elstner Associ-ates, Inc. The results were compared to the field measurements takenin 2005. This gave an interesting “snapshot” of how the pipelines’condition has deteriorated over set points in time.

The following recommendations were made as a result of the evalu-ation.

Evaluation of HDPE PipePerformance onKentucky DOT and Ohio DOTConstruction Projects

• Further monitoringof HDPE pipe installa-tions should be con-ducted.• Post video inspec-tion and deflection test-ing should be required forquality control and qual-ity assurance.• Deflection should belimited to 5 percent with theanticipation of some post-construction creep.• All previous monitoringpoints established on priorresearch projects be measured and evaluated for long-term perfor-mance.• Specifications should ensure that correct bedding and backfill re-quirements, proper densities and proper compaction are achieved asoutlined in ASTM D 2321 and AASHTO Section 30.• A quality control/quality assurance inspection program should beestablished for all drainage materials and structures.• Video inspection and laser profiling should be evaluated for adop-tion into state Department of Transportation specifications for qualitycontrol and quality assurance.

The report may be viewed at www.concrete-pipe.org under Techni-cal/Research.

Evaluation of HDPE Pipe Performance

on

Kentucky DOT and Ohio DOT

Construction Projects

by Pipeline and Drainage Consultants

the magazine of the american concrete pipe association

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