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ST8402-CN 881122(Instructions on reverse side) CHANGE ORDER PROJECT: Denton Tap Road Improvements DATE OF ISSUANCE: from Belt Line Road to Sandy Lake Road OWNER: City of Coppell P.O. Box 478 (Name. Address) Coppell, Texas 75019 CONTRACTOR: CONTRACT FOR: L.H. Lacy Co. OWNER's Project No. P.O. Box 541297 Dallas, Texas 75354 ENGINEER: Ginn, Inc. 17103 Preston Rd., Suite , Denton Tap Road Improvements L.B. 118 from Belt Line Rd. to Sandy Lake Rd. Dallas, Texas, 75248 J-378 ENGINEER's Project No. You are directed to make the following changes in the Contract Documents. Description: Substitute Portland Cement at $50.00/TON for Lime Slurry, Ty. A, 5%, 22.5#/SY at $61.00/TON (Pay Item 264); and Cement Treatment, mat. in place, 'for L/me Treatment, mat. in place at the same unit prices (Pay Item 260). Purpose of Change Order: To achieve an estimated reduction in Estimated Contract Amount of $7,624.10, while providing a constructed project which will be equal to that which was originally specified. Attachments: (List documents supporting change) 1. L.H. Lacy Co. letter of October 8, 1988 to Ginn, Inc. 2. ~lohn H. Hames ,5 Associates, Inc. October 17 1988 · etter to Ginn, Inc. ' CHANGE IN CONTRACT PRICE: Original Contract Price $. 3,362,580.00 Previous Change Orders No. N/A to No. $. N/A Contract Price prior to this Change Order 3,362,580.00 $ Net Increase (decrease) of this Change Order $ approx. ($7,624.10) Contract Price with all approved Change Orders 3,354,955.90 $. CHANGE IN CONTRACT TIME: days or dale Original Contract Time 365 Net change from previous Change Orders 0 days Contract Time Prior to this Change Order 365 days or date Net Increase (decrease) of this Change Order 0 Contract Time with all approved Change Orders days or date RECOMMENDED: EJCDC No. 1910-8-B (1983 Edition) APPROVED: by Owner APPROVED: Prepared by thc Engineers' Joint Contract Documents Committee and endorsed by Thc Associated General Contraclors of America. ' , CHANGE ORDER (Instructions on reverse side) No. PROJECT: OWNER: (Name, Address) Denton Tap Road Improvements DATE OF ISSUANCE: from Sandy Lake Road to Denton Creek City of Coppell P.O. Box 478 Coppell, TX 75019 CONTRACTOR: L.H. Lacy Co. OWNER's Project No. 10888 Shady Trail Dallas, TX 75354-1297 ENGINEER: Ginn, Inc. 17103 Preston Road, Suite 100 CONTRACT FOR: 'Denton Tap Road Improvements Dallas j TX 75248 from Sandy Lake Road to Denton Creek ENGINEER's Project No. J379 You are directed to make the following changes in the Contract Documents. Description: Substitute Portland Cement at $50.00/TON for Lime Slurry, Ty A, 5%, 22.5 #/SY at $67.00/TON and Lime Slurry TY A, 5%, 34 #/SY (9" thick) at $63.00/TON (Pay Items 264 and 264.1); and Cement Treatment, mat. in place for Lime Treatment, mat. in place at the Purpose of Change Order: sRme unit prices, (Pay Item 260) To achieve a reduction in estimated Contract Amount of approximately $6,808.00 while providing a constructed project which will be equal to that which was originally specified. Attachments: (List documents supporting change) 1. L.H. Lacy Co. letter of October 8, 1988 to Ginn, Inc. 2. John H. Haynes & Assoc,, Inc. 'letter of Oct. 17, 1988 CHANGE IN CONTRACT PRICE: Original Contract Price $ 1. 789.363.03 Previous Change Orders No. N/A $ to No. Contract Price prior to this Change Order $ 1,789~363.03 Net Increase (decrease) of this Change Order $ approx. ($6,808.00) Contract Price with all approved Change Orders $ 1~782~555.03 N/A CHANGE IN CONTRACT TIME: d~.ys or date Original Contract Time 365 Net change from previous Change Orders 0 Contract Time Prior to this Change Order 365 days or date Net Increase (decrease) of this Change Order 0 Contract Time with all approved Change Orders 365 days or date RECOMMENDED: / Enginrer EJCDC No. 1910-8-B (1983 Edition) APPROVED: by APPROVED: by Prepared by the Engineers' Joint Contract Documents Commiltee and endorsed by The Associated General Contractors of America. GINN, INC. November 22, 1988 Mr. Russell R. Doyle, P.E. City Engineer City of Coppell P.O. Box 478 Coppell, Texas 75019 CONS INEERS Re: Denton Tap Road Improvements from Belt Line Road to Sandy Lake Road; and from Sandy Lake Road to Denton Creek. Dear Mr. Doyle: This letter is a follow-up to my November 16, 1988 letter and your November 18, 1988 response concerning the proposed Change Order No. 1 to both projects for the replacement of Lime with Cement for subgrade stabilization. I am enclosing a copy of John H. Haynes and Associates, Inc. Laboratory Report No. 18, dated November 4, 1988, which states the conditions under which the Cement Stabilization will be acceptable on this project. In our discussions with the Contractor, L. H. Lacy Co., they have agreed to abide by the John H. Haynes and Associates Inc. recommendations and to apply the additional cement required near Station 91+00 to reduce the Plasticity Index to 12 or less, at no additional cost to that proposed for 5% treatment. Since this item has been reviewed and approved by our Geotechnical Engineer, and we have previously informed you of the potential cost savings of approximately $ 14,072.10 associated therewith, we feel that it is in the best interest of the City of Coppell to approve the proposed Change Orders and allow the Contractor to proceed at once with his subgrade preparation. Please call me if you have any questions. Sincerely, John C. Karlsruher, P.E. Project Engineer enclosures cc: Alan D. Ratliff, City Manager Frank Trando, Deputy city Manager H. Wayne Ginn, P.E. David M. Snyder, P.E., L. H. Lacy Co. Randy Fleming J378/379 17103 Preston Road ® Suite 100 · LB 118 · Dallas, Texas 75248 · Phone 214/248-4900 GINN, INC. CONSULTING ENGINEERS November 16, 1988 Mr. Russell R. Doyle, P.E. City Engineer City of Coppell P.O. Box 478 Coppell, Texas 75019 Re: Denton Tap Road Improvements from Belt Line Road to Sandy Lake Road; and from Sandy Lake Road to Denton Creek. Dear Mr. Doyle: I am transmitting one copy each of Change Order No. 1 for each project for approval by the City Manager. These Change Orders cover the use of Cement for subgrade stabilization in lieu of the Lime which was originally specified. The end result of approval of these Change Orders will be that a net savings of approximately $14,072.10 will be realized by the City on the two projects, while achieving a finished product which is equal to that originally specified. The Change Orders have been executed by both Ginn, Inc. and L. H. Lacy Co., and may be executed by the City Manager without Council action since each is a reduction in Estimated Contract Amount, and neither exceeds a change of more than $ 10,000.00. For your review we have attached supporting documentation upon which our recommendation for approval of the Change Orders is based. Time is of the essence, since the Contractor intends to begin stabilization within the next couple of weeks and must have a definite decision within the next few days in order to avoid delays in completion of this project. I apologize for the short notice, but we have been holding this item pending the Contractor's receipt of test reports from his laboratory confirming their verbal affirmation that the proposed subgrade treatment will be acceptable. The report has just been received, and the Contractor has asked us to proceed with processing the Change Orders. As we had verbally been assured, the proposed Cement Stabilization is acceptable, and therefore we recommend proceeding with approval of Change Order No. 1 for each project at this time. Page 1 of 2 17103PrestonRoad · Suitel~ · LBll8 · Dall~,Tex~75248 · Phone214/248-49~ If acceptable to the City Manager, please have him execute the original Change Orders and return two copies: one for issuance to the Contractor; the other for our files. You should file the Original Change Orders with your Original Contract Documents. Please call me if you have any questions. Sincerely, ~ohn C. Karlsruher, P.E. Project Engineer enclosures cc- Alan D. Ratliff, City Manager Frank Trando, Deputy City Manager H. Wayne Ginn, P.E. David M. Snyder, P.E., L. H. Lacy Co. Randy Fleming J378/379 (a:dtcemco.) Page 2 of 2 JOHN H. HAYNES ~, ASSOCIATES, INCOFIPOFIATE~O Geoteohnical Engineers November 4, 1988 L. !!. Lacy Company 10888 Shady Trail P. O. Box 541297 Dallas, Texas 75354-1297 Attention: Mr. David M. Snyder, P.E. Re: Cement Stabilization Tests Denton Tap Road Improvements Coppell, Texas Job No. 3198(b) Report No. 18 Gentlemen: As requested, we have checked the roadway subgrade along the referenced alignment to locate representative clay samples with high Liquid Limits in lhe range of about 48 to 56. Two samples were obtained and tested to evaluate their PI reduction with the use of cement. The results of these studies are shown on Plate No. 1. It was found that the dark gray clay sample having an LL of 47.5 was effectively stabilized with 5% cement addition having a reduction in PI to 10.9. ltowever, in the case of lhe sample with an LL of 55.8, 5% cement only reduced the PI to 13.3 whereas 7% cement reduced the PI to 10.7. With the exception of this lalter sample obtained at Station 91+00, all other areas of subgrade checked appeared to have lower plasticity than the other sample tested. Therefore, it is our opinion that 5% cement can be substituted for 5% lime as requested by the contractor in all areas with equal reduction in PI to below 12 wilh the exception 'of lhe area around Station 91+00. In this area (and probably up and down station maybe 100'), it is recommended that the cement factor be raised to 7% for adequate PI reduction. The actual extent of the area underlain by the higher plaslic clay (identified as light gray, dark gray and tan CH clay) should be identified on the ground by our engineering lechnician and marked for the higher concentration if cement is substituted for the specified lime material. The compaction specification that L. H. Lacy suggested to use for lhe cement stabilization work (COG Spec Item 4.9) indicates Ihe use of the THD lI3-E method. In order to reduce costs, it is our opinion that a substitution could be made whereby the Modified Proctor Method (ASTM D-1557) could be used and a minimum reqnirement of 95% Modified compaction is required. It is believed that very little difference in density will occur if this substitution is made and 95% compaction is still required. 2424 Stutz Drive · I~.0. Box 35481 · [3alias, Texas 75235 · (214) 350-5600 JOHN H. HAYNES & ASSOCIATES, INC. Geotechnical Engineers Oinn, Inc. - 2 - November 4, 1985 If we can be of furlher help, please let us know. Jlttl/jeh (2 copies submitted) cc: Mr. Randy Fleming (1 copy) Ginn, Inc. Yours very truly, JOHN H. HAYNES & ASSOCIATES, INC. - II]$ Illl I I[~ - 11111 Il [Il [ -- JOHN H. HAYNES & ASSOCIATES, ,NC. --I ~. n3 0 ~-"' Geotechnic81 Engineers JOHN H. HAYNES ~, ASSOC:IATES, INCOFIPOFIA~ GeoCeohnioal Engineers October 17, 1988 Ginn, Inc. 17103 Preston Road, Suite 100, LB 118 Dallas, Texas 75248 Attention: Mr. John Karlsruher, P.E. Re: Cement Stabilization Substitution Denton Tap Road Improvements Coppeil, Texas Job No. 3198(b) Gentlemen: In accordance with your letter request of October 12, 1988, we have reviewed L. H. Lacy's request for a substitution of 5% cement for the specified 5% lime for subgrade stabilization on this project with the change in procedural specifications to the North Central Council of Government Standard Specification Item 4.9. We believe this substitution would be acceptable provided that it is demonstrated that 5% cement will reduce the PI of all the subgrade soils along the project to not greater than 12. In our original geotechnical reports, we identified some number of plastic clays along the alignment which had Liquid Limits of 50 to 58 and PI's of 27 to 34. In order to prove lhat 5% cement is adequate, we suggest that the subgrade be checked and at least two samples of untreated clay be obtained for laboratory tests that have a Liquid Limit greater than 50. The untreated PI of these clays should be on the order of 30 to 35 and this should be proved by laboratory test. These plastic clay samples should then be treated with 5% cement and it should be demonstrated that this is sufficient to reduce the PI to not more than 12. If this is not possible, additional cement should be added until this PI reduction is achieved. All areas should then be uniformly treated with at least 5% cement or more if it is found that a greater cement factor is required to stabilize these plastic clay soils. It should be pointed out that COG Spec. Item 4.9 requires compaction to be controlled by Test Method THD l13-E. The cost of this 24 hour M6dified Proctor test is 2424 Stutz I-)rive · 1~.O. I--lox ~154EI1 · Dallas. Texas 75235 · JOHN H. HAYNES & ~/~'~SOCIATES, INC. Geotechnical Engineers Oinn, lnc. 2- August 23, 1988 higher than the 24 hour Standard Proctor test ($200 vs. $140) so a slight difference in cost will be incurred. If you have any questions concerning this report, please let us know. Yours very truly, JHll/jeh JOHN H. llAYNES & ASSOCIATES, INC. GINN, INC. October 12, 1988 CONSULTING ENGINEERS Mr. John H. Haynes, P.E. John H. Haynes & Associates, Inc. 2424 Stutz Drive P.O. Box 35481 Dallas, Texas 75235 Re: Denton Tap Road Improvements, Coppell, Tx. Dear Mr. Haynes: I am enclosing a copy of a letter from L. H. Lacy Company which is requesting that Cement Stabilization be used for subgrade treatment in lieu of Lime Stabilization as specified in your geotechnical investigations and our design for the projects. If Cement Stabilization can be used on this project, there may be a considerable savings in both construction time and cost to the City of Coppell. I would like for you to review and evaluate L. H. Lacy Company's request. In our previous conversations regarding this subject you mentioned that in order to evaluate a request such as this, some information indicating the rates of application, thickness, and acceptance criteria should be included. In reading the attached letter it is not apparent what the acceptance criteria should be, but the rates of application and thickness proposed appear to be the same as that proposed for the Lime Stabilization. If you need the results of tests, such as Ph/PI, Proctors and etc. to evaluate this request, please respond accordingly. In order to justify his request the Contractor must pay for and provide us with any test data or design data which will adequately convince you that what they are proposing will result in a finished product equal to or better than that originally specified. Please call me if you have any questions. Sincerely, · --?1 ~-~ j'. ×,' /' /" .; I /t /~_. ~.~..,. pr¢~ ect Enqineer JCK/j k enclosures cc: H. Wayne Ginn, P.E. David M. Snyder, P.E. - L. H. Lacy Co. Randy Fleming 17103 Ih'cston Road ·Suitc 100 $ IBII8 · I')allas. Tcxas 75248 · Phone 214/248-4900 GINN, INC. October 13, 1988 CONSULTING ENGINEERS Mr. David M. Snyder, P.E. L.H. Lacy Company 10888 Shady Trail P.O. Box 541297 Dallas, Texas 75354-1297 Re: Denton Tap Road Improvements from Belt Line Road to Sandy Lake Road and from Sandy Lake Road to Denton Creek, ~oppell, Texas. Dear Mr. Snyder: In response to your letter of October 8, 1988, concerning the use of Cement Stabilization in lieu of Lime Stabilization for subgrade treatment for the above mentioned projects, we have submitted the information you furnished us to John H. Haynes and Associates, Inc. for their review and comment. A copy of the letter we sent to John H. Haynes is enclosed for your use. We will await the comments from John H. Haynes and Associates, Inc. before giving further consideration to your proposal. In the meantime if more information supporting your request develops, please feel free to forward it to us. Please call me if you have any questions. Sincerely, Pro] ect ~:ng~neer JCK/jk cc: H. Wayne Ginn, P.E. Randy Fleming 17103 Prcston Road ·Suitc 100 · I.,1{ IIg · l)alla.s, Texas 75248 · Pho,c 2141248-4900 I:J 1NN.~ ].NU. 1 / 1 il).:!. F>RES i LiN RURD L)RLL. R~, I X 7~=.'48 I)ENIUN 1~4P Rt]~.~l.) IMPRLJVEMEN'f F'ROJE[:T'S FI-(DM I:tEL'i LiNE '1'0 I)EN'ION CREEl,:: I:-'fd]Jl=.[;'l b (:~.F~::I ,~,: .'";/'::~ .ql"TN: JOHN C. KARLSRUHFR, P·E. JOHN., THE L. H. LACY CO. WOULD LIKE TO FORMALIZE IT'S REQUEST FOR THE FOLLOWING ALI'ERNAI"IVE MEI'HOD OF SUBGRADE SI'ABILIZA]'ION ON BOTH OF THE ABOVE RFFERRENCED PRO,] EC l'S: SANDY LAKE 'TO DENTON CREEK PRO,] ECT (.379) i) ll'EM 264 - LIME~ 1~8 TON TO lA) I'T'EM 2~4. 1 -- LIME (9")., 504 1'ON TO ITEM 2&4 - CEMENT, 1&8 'r'ON ITEM 2&4. 1 - CEMEN'I', :~0~ ]'ON BELT LINE TO SANDY LAKE PROJECT '(578) i) ll'EM 2~4 -- LIME.', 69.3. 1 TON "FO ITEM 2~4 - CEMENT~ 695. 1 I'ON I'HE RL"fERNA1E METHOD AND SUBSEQUENT PRICE REDUCTION ARE PREDICATED ON F'OL.L~OW I NG: 1) AL.L WORK TO BE DJ]NE IN ACCORDANCE WITH THE ATTACHED NORTH TEXAS COUNCIL OF GOVERNMENT SI"ANDARD SPECIFICATIONS FOR F'UBLIC WORKS CONSI'RUCI"iI3N. (ITEM 4.9) 2> A ONE' -FO ONE (1 'TO 1) SUBSTITUTION OF CEMENT FOR LIME (AS REFLECTED ABOVE ) . I'HE L. H. LACY COMPANY PROPOSES THE FOLLOWING PRICE REDUCTIONS IN CONSID- ERAI'ION I]F' THE PROPOSAL. AS IT IS S'I'A'I'ED iN 1HIS LETTER, ANY CHANGE IN MEI'HOD OR QUAN'I'ITIES FROM "FHOSE F'ROF'OSED WILL REQUIRE A RESPONSE FROM L. H. LACY CO. L H, Lacy Company General Contractors 214/357-0146 "Quality Construction for over 65 Years" 10888 Shady Trail P.O. Box 541297 Dallas, Texas 75354-1297 SI~NDY LAKE fO [,~EN'T'[IN CREEK I='F(O,] E(:T (:~.79) 1) I'"I"EI'I ?,':/I - £:Ei]'Ii~:N'I'.~ lg:,[:] "I"ON ,~ $SC).I'~-)/"I"ON (FIF"I'Y DOL. LARS i::'L=.R "I"L3N) l~'a) ~"I"EI'I 2~/I-. ]. - CEl"lli:..l'~'f' (9"): ?',0,1 "I'ON ;~) '~SC).O0/"['ON (I:'~FTY DOL. LI.~f(S F'EF(]"ON) 1:-'1:'¢03 EC'I' ( :378 :~ ~t~50.OL)/'¥ON (FIF'"I'Y DOL_L~'-~F¢S [:'ER TON) IN ADDITiI]N 'l"O THE CC)~;'f' S~'~VINGS F:OIR THE CITY OF COPPELI. IN SUPPL. Y INL~ EQUAL [')1~ J~:~ET'I'ER F'F((:)[)UCT.~ THE L. H. L.~CY COHI:'t.~NY LdOLJLI) LIKE Gi'NN., I'.:ONSI£)I?.'R ]'HP' '/IHI":]..Y Nt.~TU['~I~ 01:: THt'::SI~.: PI:~O,]E£:'I'S., THE I~t. IVI3R/.~£~LI:: TYPES OF THE V~-~RIE)L.J'3 SU~3(']R~:~DE Ht-~'I'E~:~P..,L.S PRESE'NT ON THE ,]OL~S TO }liE ST~B[L/ZED., L. H. L~CY;'S PREV):E)US SUCCE:SSES WI'I'H S[Mli_~R (:EHENT-TREA"T'ED StJB6R(-~DE AI_T- I'~ATES F./ND THE INHER~EN'I I"I'HE-'3~.'~VINI3S £]U;-~LI'¥IE..S OF THIS METHOD OF L I ZA'T l EJN. Af5 ~ REHJNDER TH]'S I,,JL:)RI.::. IS SCHEDULED FOR 'THE NE/AR FUTURE~ NE~ REf2LJE'ST THE F:/~M(:JF:~ 01=' Y[:JUI:~ F~Ef:'I_Y SI} NE CI-'~N I~:ZXECU'I'E I='UF~(:Hf.~,SE OR])I':F(S F'OF( 'I"HI::' I~1(A'1'1~:1:¢~tl_~ [""T(:. 'I'H¢-~NI::.-.-YOLJ ~:'12)[{ YL]LJ[{ COl,l':;J DER/-'~T iON 1N TH!S ~L..'I'ERNATE IqE'I'HOD OF'" 'CDNs'rRUCT ZON. I:)~4VID Pl. SNYL)ER: F".E. EI',IC: liNE (1) (::OF'Y [')F Nt:)[~'l'l-t -I'EX~-tS CoIJr,ICIL OF GOVEF~r,II'IE-.'NT Sl::'[{C 1 F' 1 I".'(-YI' ]: [INS F'CJF( f:'tJ£q_ 1 C I,,JOl:~K.c:'i I:(::ll~lEi'l"l:~tJl:'l 1 ON., ~ I 'l"Erq '~t. ~1 ) . CC: I-:~ []lXl Hc/-~VO Y [:' 1 Lli: :1 10 CO[~I:'qi:.'SI::'OI',IDENC[ii. tance by the OWSER. Repairs are to be made in a manner which shall insure restoration of a uniform surface. Durability of the part required shall be measured in its final position and the volume computed in cubic yards (Ms) by the method of average end area. Soil-asphalt course shall be measured by the square yard (M~) of sur- face area of completed and accepted work based on the width of the soil-asphalt course as shown on the plans, or as established by the owsER. Asphaltic material of the type and grade shown on the plans shall be measured In gallons (liters) at the applied temperature at the point of application on the road. Work performed and materials furnished as prescribed and measured by this item shall be paid for at the unit prices bid for soil-asphalt course and additional soil, which priees shall be full compensation for cleaning the roadbed or the surface of the previously completed base course; for furnishing all materials; for loosening excavating, loading, hauling and delivering additional soil on the road; for loosening, mixing and pulverizing of the soil; for shaping, sprinkling and compacting the subgrade; for all processing, mixing, drying, incorporation of asphaltic material, aerating and drying, spreading, sprinkling, shaping, compact- lng, and finishing; for maintaining under traffic; and for all manipula- tions, labor, equipment, fuels, tools and incidentals necessary to com- plete the work except as hereinafter provided. Asphaltic material measured as provided in this item shall be paid for at the unit price bid for asphaltic material, which price shall be full compensation for furnishing the material; for all freight involved; for all unloading, storing, heating, hauling and applying on the read; and for all labor, equipment, fuels, .tools and incidentals necessary to complete work. ITEM 4.9.PORTLAND CEMENT MODIFICATION OF SUBGRADE SOILS 4.9.1. DE~RIPYION: This item shall consist of the treating the sub- grade soils by pulverizing, addition of portland cement and water, mixing and compacting the mixture to the required' d~nsity. This item applies to natural ground or embankment encountered in the con- struction. The cement-modified soil layer shall be constructed as specified herein and in conformity with the typical sections, lines and grades as shown on the plans or as established by the 4.9.2. MATERIALS: (a) Portland Cement. Cement shall conform to the requirements of Item 2.2. L, "Cement." (b) Water. Water shall conform to the requirements of Item 2.2.4., '%Vater." (c) Soil. The soil shall consist of approved soil, free from vegetation or other.objectionable matter. It may be either the material encountered in the existing section, material secured from approved sources shown AUGUST 1M7 on the plans or as designated by the ow~-a, or a combination of existing and additional soil from approved sources, as shown on the plans, or az directed by the ovm~a. 4.9.3. EOUIPM£NY: All equipment necessary to properly prosecute, perform and complete the work within the contract time, shall be on the project and shall be approved by the owsza as to type and condition be- fore the cosr~Acrog shall be permitted to begin construction operations on which the equipment is to be used. The cement-modified soil layer may be constructed with any machine or combination of machines and auxiliary equipment that shall produce the results meeting the requirements for soil pulverization, cement ap- plication, water application, mixing, incorporation of materials, compac- tion, and finishing as specified herein. The CONTR~tCTOR shall at all times provide sufficient equipment to enable continuous performance of the work and its completion in the required number of working days. 4.9.4. CON$?IqUCTION Mh-I'HOD$: (a) C_,eneral. The primary requirement of this specification is to secure a complete course of treated subgrade material containing a uniform portland cement mixture, free from loose or segregated areas, of uniform density and moisture content, well bound and compacted for its full depth with a smooth surface suitable for placing additional sub- base, base or surface courses. It shall be the responsibility of the ¢os~'aAcvoa to regulate the sequence of his work to process a sufficient quantity of material so as to provide full depth as shown on plans, to use the proper amount of portland cement, maintain the work and to rework the courses as necessary to meet the foregoing requirements. Before other construction operations are begun, the roadbed shall be graded and shaped as required to construct the portland cement modified subgrade layer in conformance with the lines, grades, thickness and typical cross sections shown on the plans. Unsuitable soil or material shall be removed and replaced with acceptable soil. The subgrade shall be firm and able to support without displacement the construction equip- ment and the compaction hereinafter specified. Soft or yielding subgrade shall be corrected and made stable before construction proceeds. (b) Application of Cement. Portland cement shall be spread uni- formly by an approved dry or slurry method on the soil at the rate specified on the plans or as determined by preliminary laboratory tests. If a bulk cement spreader is used, it shall be positioned by string lines or other approved method during spreading to insure a uniform distribu- tion of cement. Cement shall be applied only to such an area that all the operations can be continuous and completed in one operation. The percentage of moisture in the subgrade soil at the time of cement application shall not exceed the qmmtity .that shall ~permit uniform and intimate mixture of soil and cement during dry-mixing oper- ations; and it shall not exceed the specified optimum moisture content for the soil and cement mixture. No equipment, except that used in the spreading and mixing, shall be allowed to pass over the freshly spread cement until it is mixed with the soil. AUGUST lg87 ' J 4.e.4 2e3b (c) Mixing and Processing. The mixing procedure shall be the same for "Dry Placing" or "Slurry Placing" as described herein. The material and cement shall be thoroughly mixed by approved road mixers or other approved equipment and the mixing shall continue until, in the opinion of the Engineer, a homogeneous, friable mixture of material and cement is obtained, free from all clods or lumps. Materials containing plastic clays or other material which will not readily mix with cement shall be mixed as thoroughly as possible at the time of the cement application and brought to the proper moisture content. The material shall be kept moist as directed by the Engineer. The cement-soil mixture shall meet the following gradation require- ments when tested dry by laboratory sieves: Minimum Passing 1" Sieve ........................... 100% Minimum Passing l/z~ Sieve .......................... 70% Minimum Passing No. 4 Sieve ............. ~; ....... 45% (d) Compaction. Compaction shall begin immediately after final mix- ing. The material shall be compacted to 95% of the maximum density, as established, and in accordance with Test Method Tex I13-E. It shall be aerated or wetted as necessary to provide optimum moisture. Moisture tolerances shall be as described below. Prior to the beginning of compaction, the mixture shall be in a loose condition for its full depth. Compaction shall begin at the bottom and shall continue until the entire depth of the mixture is uniformly compacted. Description Density, Percent Moisture, Percent For cement treated Not less than 95, Within 2.5 of subgrade that will except when shown optimum unless receive subsequent otherwise on the otherwise shown courses, plans, on the plans. In-Place Density tests shall be as outlined in Test Method Tex l14-E or Test Method Tex llS-E. In-Place Density tests shall be performed at the rate of one per 300 linear feet of paving for two (2) lanes. The suita- bility of the stabilization shall be confirmed by Atterberg Limit testing at the rate of one test per 2,500 cubic yards of processed material. In addition to the requirements specified for density, the full depth of the material shown on the plans shall be compacted to the extent necessary to remain firm and stable under construction equipment. After each section is completed, tests as necessary will be made by the Engineer. If the material fails to meet the density requirements, it shall be reworked as necessary to meet these requirements. Throughout this entire operation the shape of the course shall be maintained by blading, and the surface upon completion shall be smooth and in conformity with the typical section shown on the plans and to the established lines and grades. Should the material due to any reason or cause, lose the stabll- ity, density and finish before the next course is placed or the work is accepted, it shall be recompacted and refinished at the sole expense of the CONTRACTOR. (e) Finishing and Preparation for Surfacing. After the final layer or course of the cement-modified subgrade has been compacted, it shall be brought to the required lines and grades in accordance with the typical sections. The completed section shall then be finished by rolling as di- rected with a pneumatic tire or other suitable roller sufficiently light to prevent hair cracking. Preparation for final surfacing may begin ira- mediately. 4.9.5. MAINTENANCE: The COSrP.~CrOR shall be required, within the limits of his contract, to maintain the cement-modified soil in good cendi- tion from the time he first starts work until all work shall have been completed. Maintenance shall include immediate repairs of any defect that may occur after the cement is applied. Such maintenance work shall be done by the CO~?RACrOa at his own expense and repeated az often as necessary to keep the area continuously intact. Repairs are to be made in such a manner as to insure restoration of a uniform surface for the full depth of treatment. Any low area shall be remedied by replacing the material for the full depth of treatment rather than adding a thin layer of stabilized material to the completed work. 4.9.6. MEASUREMENT AND PAYMENT: This work shall be measured by the square yard (M") of completed and accepted cement-modified soil. Measurement for cement shall be by the ton, 2,000 pounds (900 kg) of dry weight, as determined by certified weight tickets. No allowance shall be made for any materials used or work done outside the Limits as established by the ow~.a. The work performed and material furnished as prescribed by this item and measured as provided in this item shall be paid for at the unit price bid for cement-modified soil, which price shall be full compensation for pulverizing the soil material; for handling; haul- ing and spreading the dry or slurry cement mixture; for mixing the cement with the pulverized soil; furnishing, hauling and mixing water with the cement-soil mixture; spreading and shaping the mixture; com- pacting the mixture, including all relling required for this compaction; surface finishing;, and for all manipulation, labor, equipment, appliances, tools and incidentals necessary to complete the work and carry out the maintenance provisions in this specification. Cement material measured az provided in this item shall be paid for at the unit price bid for cement material, which price shall be compensation for furnishing the material; for all freight involved, for all unloading and storing; and for all labor, equipment, fuels, tools and incidentals necessary to complete the work, all in accordance with the plans and these specifications. AUGUST d ~ F~o?, pv,~4'?. 5F_~-I-I OIN ~ b---FA. 191 +~0 BIT "B" ¢-rZd 14. ~ It':~' V. / /1 / NOTE: STUBOUT -3a IS USE 8~ WILL D FOR FUTUR~ SERVICE PORTIONS OFI AREAS I0 AND II. CAUTION l! EXIST. GTE DUCT AREA. TO BE EEl BY OTHERS. THIS ii= 456.97 PAY ITEM 475.21 OTE= EXTRA DEP~ 7'- x RCBC II LAT. 24"R( 2- 8' x4' RcBc 147 LF ea. R.O.~. L/ne · fer E'sm'! I AD'JUS-T F.H..-;'.q'?! 1 .?_L.,'r E.. 5s&sj:,,.:' F~'DJUST [PAY ITEM' ADJUST W. PAY ITEM 2-2" PVC 221 L STA. 191 +94.64 2-10' REC'D. INLETSJ T.C 52.89 w CI-IA~E 0EPt~-~, I' Ii ¢ Z ~_.CT~O NI e. 5T4. 1~5+ O0 I STA. 194+50 I1-10' REC'D. INLET {,MOD] I i~C. = 4 64.46 = 456.96 IPAY ITEM 475.21 L~TE: EXTRA DEPTH INLET r EXIST. G.T.E.M.H. TO BE I ADJUSTED BY OTHERS i I b = 2° 30' 00" LT.__ --.--J I STA. 196+ 80 P.I.- 38.5' LT. I I A = 2° 30' 00" RT. Wa/er Esm '! F..~ &" ?~c -., IADJUST F H.~ ~.V.-] [PAY ITEM 582_.3 ?-~L~: I"= ~0~