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HomeMy WebLinkAboutResolution - 6280 - Amendment #3 To Engineering Agreement - Delta Airport Consultants Inc - LIA - 04_22_1999J Resolution No. 6280 Item No. 29 April 22, 1999 RESOLUTION BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF LUBBOCK: THAT the Mayor of the City of Lubbock BE and is hereby authorized and directed to execute for and on behalf of the City of Lubbock, an Amendment No. Three for professional engineering services and supervision of improvements at Lubbock International Airport, by and between the City of Lubbock and Delta Airport Consultants, Inc., and related documents. Said Amendment No, Three is attached hereto and incorporated in this resolution as if fully set forth herein and shall be included in the minutes of the City Council. Passed by the City Council this 22nd day of Aril , 1999. INDY S , MAYOR A -ST: PAALL Kaytdcretary Darnell City APPROVED AS TO CONTENT: Mar ar e Director of Aviation APPROVED AS TO FORM: William de Haas Competition and Contracts Manager/Attorney rkb/ccdocs/1999 airport.res March 30, 1999 Resolution No. 6280 Item No. 29 April 22, 1999 AMENDMENT NO. THREE (3) TO THE ENGINEERING AGREEMENT BETWEEN CITY OF LUBBOCK, TEXAS the OWNER AND DELTA AIRPORT CONSULTANTS, INC. the ENGINEER DATE: MARCH 17, 1999 DELTA PROJECT NO. TX 97053 TASK 2 - RECONSTRUCT RUNWAY 17R-35L KEEL (Construction Phase) 4007 AMENDMENT NO. THREE (3) TO THE ENGINEERING AGREEMENT BETWEEN OWNER AND ENGINEER FOR PROFESSIONAL SERVICES MARCH 17, 1999 TASK 2 RECONSTRUCT RUNWAY 17R-35L KEEL (Construction Phase) This AMENDMENT NO. THREE (3), dated March 17, 1999, is made a part of the Engineering Agreement dated May 22, 1997, between the City of Lubbock, Texas, the OWNER, and Delta Airport Consultants, Inc., the ENGINEER, for work at Lubbock International Airport, Lubbock, Texas. The following revisions and/or additions are made to the original Engineering Agreement: ADD the following paragraph to Article 7: 7.13 Task 2 - Additional Services - Concrete Testing to be completed as part of current construction phase services shall be compensated on a unit price basis. Compensation shall be limited to a budget amount of $18,700 unless written authorization has been received from the Owner. The budget amount is based upon the estimated costs shown in Attachment Amd 3-1. The following attachment is made part of this Amendment: Attachment "Amd 3-1": Budget Estimate All other provisions of the original Agreement remain unchanged. 19010" City of Lubbock 1625 13th Street, Suite L-04 Lubbock, Texas 79401 Windy Sitton Mayor Date: April 22, 1999 ATMST: APPROVED AS TO CONTENT: Marls . arle, Director of Aviation 70534007.ao3 2 ENGINEER: Delta Airport Consultants, Inc. 500 W. 7th Street, Suite 501 Ft. Worth, Texas 76102 Susan E. Winslow, P.E. Vice President Date: �'// 7 r q Notary FORD E DE3�ifE000ERE NOTARY PUBLIC exr cann, b*. 01,2aQooa APPROVED AS TO FORM: ATTACHMENT "AMD 3-I" BUDGET ESTIMATE L7EL.. /4 N, i4107POR7- 4CONSUL7i4N7-29, IMC. engineers - Charlotte, NC Fort Worth, TX Richmond. VA February 5, 1999 Mr. Mark N. Earle Director of Aviation Lubbock International Airport Route 3 Box 389 Lubbock, Texas 79401 RE: Reconstruct Runway 17R-35L Keel Lubbock International Airport Lubbock, Texas AIP Project No. 348-0138-19-97 Delta Project No. TX 97053 Dear Mr. Earle: Please find enclosed subconsultant's proposal for the concrete testing to be completed on the prematurely cracked panels on the referenced project. Our estimated cost for this work is as follows: APTech (testing and report) $15,350 Terra Engineers (pavement coring) S3.350 $18,700 There are sufficient funds remaining in the project budget to cover these testing costs. Please advise our office if this is acceptable. We are ready to begin this work immediately, and anticipate that the coring, testing, and report submittal will be completed within six to eight weeks from approval to start. Please do not hesitate to contact our office if you should have any questions. Sincerely, • I . Susan E. Winslow, P.E. SEW:hm Enclosure cc: Linda Stoltz, FAA-TXADO Ken Moody, Delta Charlotte 7053c532.doc w/ encl wlent] 500 West Seventh Street, Suite 501 Fort Worth, Texas 76102 Homepage:http://www.deltaairport.com Telephone (817) 348-8301 Fax (817) 348-8304 E-mail:delta@deltaairport.com PROPOSED LUBBOCK SCOPE PROJECT APPROACH In 1998, the keel section of runway 17R-35L was replaced. Although most of this replacement was conducted using conventional paving techniques, operational constraints in certain areas required that concrete replacement be done using small pours. Additional paving using small pours was also performed in the panels with touch -down zone (TDZ) lights. Shortly after construction, cracking was noted in some of the newly paved areas. This cracking appeared to be more extensive in the TDZ, where the slabs were reinforced, but has also been noted in other locations as well. An inspection in October 1998 suggests that the cracking is progressive, increasing in both extent and severity over time. This is of concern, as it may have a significant impact on the life of the pavement. In addition to the TDZ light slab cracking, other observed distresses include longitudinal cracks in the keel reconstruction and some surface scaling. The Owner wants to determine whether or not the observed condition of the concrete will have an adverse effect on the structural performance of the pavement. Furthermore, if the concrete is not sound, or if there are areas of the concrete that are not sound, recommendations are desired regarding either remediation or replacement. The following brief scope of work outlines APTech's proposed approach to addressing the owner's concerns, using both APTech's engineers and staff from Michigan Technological University (MTU). Task 1. Records Review and Sample Retrieval The evaluation must begin with a thorough review of the relevant construction and climatic records. The project team will prepare and evaluate maps of the runway containing such information as the various pour locations, evaporation rates for each day's placement, temperature fluctuations, and the type, severity, and extent of the observed distresses. As part of the review process, special attention will be paid to the concrete mix properties and placement temperatures. Additional information that may prove to be relevant includes reinforcement placement, concrete slump readings, air contents, gradation tolerances, and reported cement contents and water -cement ratios if available. A thorough evaluation of this data will provide a clearer picture of the potential distress mechanism. Task 2. Perform Examination of Concrete Cores From the maps of pavement distress, pour locations, and evaporation rates, core locations will be selected to provide a representative sample of material types and distress levels. It is believed that a total of 10 pavement cores is sufficient to adequately describe the current conditions. Distinctive surface patterns are associated with the various causes of early cracking in concrete pavements. For example, plastic shrinkage cracking appears as map cracking, not dissimilar to the pattern observed on a dry lake bed. Cracking caused by thermal shock (due to rapid change in ambient temperatures shortly after paving) can be longitudinal or transverse, but typically start as partial width cracks that ultimately progress completely across the slab. Cracking due to late joint sawing parallels the joints, and will commonly be a working crack, opening and closing with fluctuations in temperature. Task 3. Analyze Core Specimens and Summarize Results Upon receiving the selected cores, each will be prepared for further analysis. The first step is to cut the cores along the Y-axis, creating a number of slabs. One slab side will be polished extensively to investigate, among other things, the degree of consolidation or segregation, adequacy of mixing, the parameters of the air void structure, the type and depth of cracks, and the type and relative size distribution of the aggregate used. The type and depth of cracking will be a primary diagnostic tool in this investigation. This initial analysis, conducted with a stereo microscope, will help direct additional investigations using a petrographic and/or scanning electron microscope if needed. Thin sections will also be made from each core to determine if fly ash is present, and if so, in what quantity. These thin sections will be impregnated with a fluorescent epoxy to evaluate the relative difference in capillary porosity between the various concrete under investigation. The capillary porosity is directly related to the water -cement ratio, and thus differences in the water - cement ratio between the various concretes will be obtained. Fluorescent epoxy impregnation is also a powerful tool in analyzing microcracking in concrete, and thus will be of use in study the observed cracking. Because the pavement is so new, there is little chance that the observed distresses are due to a common materials -related distress, such as sulfate attack or alkali -silica reactivity. But if preliminary analysis reveals some unusual or unexpected features, additional testing may be required to fully analyze the cores. Upon completion of all the required tests, an assessment of the probable cause(s) of deterioration will be made. Task 4, Make Rehabilitation Recommendations The analysis of the concrete materials and the results of the brief post -construction survey will be used to define the extent of the problem and make recommendations for rehabilitation. Rehabilitation recommendations are likely to range from doing nothing to removal and replacement. Other options that will be considered include surface sealing, crack sealing, and surface milling and replacement, based on the identification of the problems' causes. During this task, all of the results and recommendations will be summarized in a written report and, if desired, presented to the client. PROJECT BUDGET Michigan Tech APTech Travel Total Task 1 $500.00 $2,000.00 $850.00 $3,350.00 Task 2 $5 000.00 $5 000.00 Task 3 $3 000.00 $3 000.00 Task 4 $1 000.00 $9,500.00 $3 000.00 $4 000.00 TOTAL $5,000.40 $850.00 $15,350.00 PROJECT SCHEDULE Once notice to proceed is provided, the work will begin with the retrieval of the cores. We believe that the work can be completed in approximately b to 8 weeks.