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Freeport NIP(2.5)-SP 980120 EXCAVATION SAFETY SPECIFICATIONS FOR .. WATER MAIN SANITARY SEWER STORM DRAIN TO SERVE NORTHPOINT BUSINESS CENTER FREEPORT NORTH CITY OF COPPELL, TEXAS Contractor: Patco Utilities, Inc. 1617 W. Hwy 303 Grand Prairie, Texas Prepared By: M.W. Custer, P.E.- 5006 Oak Springs DJ. Arlington, Texas 76016 817-483-5579 File No.;98115 PRtco Ugliifes 1 Nor~point Business Center File No. 98115 Coppe/I, Texas I1.0 DESIGN ASSUMPTIONS , , , ~ 1.1 General. These specifications cover the basic requirements for shoring and/or sloping of excavations for installation of Storm Drain, Sanitary Sewer and Water Lines for the Northpoint Business Center Project, CoppelI,Texas. 1.2 This specification addresses the safety of workers in a trench excavation and does not, in any way relieve the Contractor of his responsibility and liability to ensure the safety of the project and workers. 1.3 It is not the intent of these specifications to specify every detail and procedure of the trenching/shoring operations; nevertheless, they shall conform to the high standards of engineering and of safe trench excavation. 1.4 The personnel protection systems shown in these specifications have been designed based on information obtained from 'the project drawings. 1.5 The personnel protection systems shown in these specifications have been designed based on an assumed subsurface of Type 'B' Soils. In accordance with Revised OSHA (effective March 2,1990), prior to beginning construction, The contractor's "Competent Person" will conduct the required Soil Classification Tests. If soils other than those identified are found, this specification will be revised. During construction, the contractor's "Competent Person" will monitor the soil classification as required by OSHA 1926. 1.6 Contractor shall be responsible for selecting appropriate safety system option shown in these specifications depending on trench depth and soil conditions. 1.7 The protection of existing structures and utilities which may be affected by these trench excavations is beyond the scope of this report. 1.8 The Contractor must identify a "Competent Person" in the Contractor's firm responsible for performing inspections of the excavations to ensure that expected subsurface conditions are present. If conditions in the field vary from the expected conditions, the design engineer shall be contacted, for possible design' modifications prior to personnel entering the excavation. Note -This person must be "Competent" as described in OSHA 1926.650 (b). 1.9 It is the Contractor's responsibility to ensure that all excavation work and site conditions are within the regulations as established by O.S.H.A. Any property damage or bodily injury (including death) arising fro~ the use of these specifications, from Contractor's negligence in performance of contract work, or from Owner's failure to note exceptions to these specifications shall remain the sole responsibility and liability of the contractor. Patco USli~s 2 Norlhpoint Business Center Rle No. 98115 Coppell, Texas 12.0 DEFINITIONS 2.1 All definitions of section 1926.653 of Subpart P, Part 1926, of the Code of Federal Regulations shall be by reference an integral part of this section. 2.2 "Sealing Engineer" - The engineer whose Texas seal is affixed to these specifications. 2.3 "The Contractor" - The contractor responsible to the owner for the excavation work described herein. 2.4"Competent" as described in OSHA 1926.650 (b). 13.0 APPLICABLE CODES AND STANDARDS 3.1 The Contractor shall perform all shoring work under this contract in accordance with all applicable codes and standard safety requirements and regulations including: 3.1.1 OSHA 2207, Construction Industry Standards(part 1926 Occupational Safety and Health Standards) 3.1.2AISC Code of Standard Practice 3.1.3AISC Specification of the design, fabrication, and erection of steel buildings. 3.1.4AITC Timber Construction Manual 3.1.5AWS D1.1 Structural Welding Code 3.1.6The Uniform Building Code 3.1.7OSHA 2226 3.2 The latest edition (including supplements and revisions) of the above publications in effect or promulgated at the time of the bid shall apply. Equipment fabricated to codes and standards in effect at time of bid but later revised shall be acceptable provided such revisions are not required by law. 14.0 SHORING/SLOPING REQUIREMENTS 4.1 Description. This section covers the technical requirements of the trenching/shoring work. 4.2 Existing Structures. Where existing buildings, other utilities, streets, highways, or other structures are in close proximity to the trench, or may otherwise be affected by the proposed trenching operation, the Contractor shall provide adequate protection by the use of sheeting and shoring to protect the structure, street, or highway from possible damage. In the case of utilities, the Contractor may elect to remove the utility provided that the removal and subsequent replacement meets with the approval of the engineer, the utility owner, or whoever has jurisdiction of the structure. In all cases, it shall be the responsibility of the Contractor to protect public and private property and any person or persons who might, as a result of the Contractor's work be injured. Patco U~rt~s 3 · No~hpoint Business Center Rle No. 98115 Coppell, Texas 4.0 SHORING/SLOPING REQUIREMENTS Cont'd. , 4.3 General Trenching and Shoring Requirements. The contractor shall be solely responsible for trench safety provisions meeting the applicable requirements of the United States Department of Labor Occupational Safety and Health Administration including subpart P, Part 1926 of the Code of Federal Regulations. All trenching operations and procedure shall also conform to the .~ requirements listed in this specification. 4.3.1 The requirements of sections 1926.50 and 1926.651 of Subpart P, Part 1926, of the Code of Federal Regulations shall be by reference an integral part of this section. 4.4 Requirements Prior to Excavation Activities. 4.4.1 Known underground installations are shown on the site plans. It is the Contractor's responsibility to verify exact locations in the field. 4.4.2 Before any individual enters an excavation, the excavation will be inspected by a "Competent Person" to ensure that trench excavation has been performed according to this specification and O.S.H.A. requirements and to ensure that no anomalies are observed which may effect the safety of the trench or project. Note -This person must be "Competent" as described in OSHA 1926.65(b). 4.5 Requirements During Excavation Activities. 4.5.1 During excavation, the exact location of existing underground installations shall be determined by the Contractor, and when uncovered, proper precautions and supports shall be provided so as not to cause a hazard to the workmen or project. 4.5.2 Daily inspections of the excavations shall be made by the Contractor's "Competent Person". If there is evidence of possible cave-ins or slides, all work in the excavation shall cease until the neceSsary precautions have been taken to ensure the safety of the workmen and the trench. Note -This person must be "Competent" as described in OSHA 1926.650 (b). 4.5.3 Excavations shall be inspected after every rainstorm or other hazard-increasing occurrence to ensure tl~e safety of the workmen and the trench. PaSo USliges 4 Nor~point Business Center F'#e No. 98115 Coppell, Texas 14.0 SHORING/SLOPING REQUIREMENTS Contld. ~ 4.5.4 Excavated material shall be stockpiled a distance away from the trench, so as not to affect the trench stability. The contractor's construction means and methods will determine the distance. As a minimum to protect the workmen from falling debris, the toe of the stockpiled soil shall be no closer than two (2) feet from the edge of the excavati°n. ' '- 4.5.5 All precautions must be made to prevent surface water from entering the trench excavation. Adequate drainage must be provided in the area adjacent to the excavation. 4.5.6 Operation of heavy equipment adjacent to the edge of the trench may cause instability. The Contractor is responsible for the means and methods of excavation, and therefore, for loads imposed on the trench excavation and shoring design. 4.5.7 The Contractor must take precautions to protect the face of the excavation from exposure to freezing. 4.5.8 Water shall not be permitted to stand in the bottom of the trench and suction pumps of adequate capacity shall be installed to ensure that such standing water is removed. 4.5.9 The Contractor shall provide a positive means of ensuring that hydrostatic pressure does not build up behind the shoring or shields. 4.5.10 If a condition requiring the use of a different method of shoring is encountered, this specification will be revised. 4.5.11 Remove shoring units from bottom to top as backfilling proceeds. 4.5.12 When backfill is within five (5) feet of the top of the trench, all shoring may be removed, unless the trench conditions indicate a hazard. 4.5.13 No person shall be exposed to the lower portion of the trench after shoring has been removed. 4.5.14 Additional shoring or larger sizes may be installed. 4.5.15 Ladders or other adequate means of exit must be provided and located so as to require no more than 25 feet of lateral travel. 4.5.16 When two trenches intersect, both trenches must be protected to a distance of not less than the depth of the' deepest trench. Parco Ut~i~es 5 Norlhpoint Bus/ness Center Rle No. 98115 Coppell, Texas 14.0 SHORING/SLOPING REQUIREMENTS 4.6 Shoring Alternatives for this Work 4.6.1 Trenches more than 5 feet deep shall be shored, laid back to a stable slope, or some other equivalent means of protection shall be provided where employees may be exposed to moving ground or cave-ins. Trenches less than 5 feet in depth shall also-be effectively protected when examination of ground indicates hazardous ground movement may be expected. The contractor will have options for providing such protection. 4.6.2 Lateral Earth Pressure P= a uniformly distributed lateral soil pressure, in lbs./ft.2 We= Effective Soil Weight, pcf H= depth of excavation from top of supported bank to bottom of excavation, in feet. Hq= Equivalent Height of Surcharge, ft. P= We*(H+Hq) (Reference OSHA Rules and Regulations-Part 1926 of 29 CFR as amended by the Federal Register Volume 54, Number 209, dated October 31,1989. 4.6.3 Option I The contractor can use Slope as shown in the Option I section of this specification. See Drawing 1 and General Notes-Slope 4.6.4 Option II The contractor can use Trench Shield as shown in the Option II section of this specification. See Drawing 2 and General Notes-Shields 4.6.5 Option Ila FOR BORE/EXIT PITS The contractor can use Trench Shield as shown in the Option Ila section of this specification. See Drawing 3 and General Notes-Shields 4.6.6 Option III The contractor can use Aluminum HydraulicTrench Shores as shown in the Option III section of this specification. See Drawing 4 and General Notes-Trench Shores. Parco Utililfes 6 Northpoint Business Cen~er File No. 98115 Coppell, Texas !GENERAL NOTES-Slope I 1 .) A maximum allowable slope of 1.0 (horizontal) to 1.0 (vertical) may be used during trench excavation in soil materials in lieu of trench shoring systems. Soil materials that could be sloped to this configuration include clayand sandy clay. This temporary slope configuration represents the steepest incline for short-term conditions (a time period less than 72 hours) that is acceptable given probable but subjective influences from rainfall and normal equipment vibrations.' However, if during excavation or construction of this project there is any indication of general or local instability, slopes shall be cut back to a slope which is at least 0.25 (horizontal) to 1.0 (vertical) flatter than the specified slopes outlined previously, i.e., this translates to a total slope of 1.25 (horizontal) to 1.0 (vertical). This flattening of the slopes may be required due to the deterioration of the shear strength with time or due to trench flooding, instability induced from excessive adjacent vibrations (resulting from equipment operation), excessive adjacent surcharge loads due to equipment or stockpiled excavated materials, shrinkage cracks due to drying, etc. 2.) Additional flattening of slopes is required when any of the following conditions are present; 1 .) Slopes in soft loose soils or fill materials shall be flattened to 2:1 2.) If an existing parallel utility line is located within a horizontal distance equal to the depth of the new utility excavation, all slopes shall be flattened an additional 0.5:1. 3.) Contractor's "Competent Person" shall monitor the excavation to evaluate subsurface conditions and determine soil type and condition. When contractor's "Competent Person" cannot assure that the slope is suitable for safe use, a qualified soils engineer shall be consulted. See Drawing SLOPE for additional requiremenrts Pa~co Ut~i~es 7 Nor~po~nt Business Cen~er File No. 98115 Coppell, Texas I GENERAL NOTES-Trench Shields i 1 .) A Trench Shield is a structure that normally will not prevent a cave-in, but is able to withstand the forces imposed on it by a cave-in and thereby protect workers within the structure. Trench Shields are also referred to as "Trench Boxes". These general notes also are applicable to Manhole Shields. 2.) A "Pre-manufactured Shield" is a product designed,- constructed and marketed to the construction industry as a method of protecting personnel while working in trenches subject to cave-ins. 3.) A "Shop-built Shield" is defined herein as a shield built by a contractor or his agent for their own use as a personnel protection device and is not available commercially as a product to the construction industry. 4.) Acceptable Shield Systems: Pre-manufactured shields are commercially available and may be used provided that the shields are selected and used in accordance with the manufacturer's specifications, recommendations and limitations. Deviations from manufacturer's specifications, recommendations and limitations will not be allowed without the manufacturer's specific written approval. This specific written approval of deviations must be kept at the jobsite along with the manufacturer's specifications and recommendations for use and other instructional use literature for the specific shield. 5.) Shop-built shields may be used, when designed and sealed by a professional engineer registered in the state of Texas and having a background in the practice of structural engineering. 6.) Ail shields must be free from damage or defects that might impair their proper function. Shields shall be used and maintained in a manner consistent with the recommendations of the manufacturer or design engineer. Damaged shields shall be removed from service until authorized repairs are made. 7.) Shields shall be installed in a manner which restricts lateral or other hazardous movement of the shield in the event of the application of sudden lateral loads. Where trench shields are stacked, a mechanism must be available for connecting the shields to prevent differential movement between the shields when subjected to laterals. Benching of earth material below the bottom of the shield is allowed to a maximum of 2.0 ft., when this benched material is of sufficient strength to support the shield. 8.) Workmen shall not be allowed in shields when shields are being installed, removed or moved vertically. A ladder or other safe means of entry and exit shall be located such that workmen are not exposed to a potential cave-in hazard during entry or exit from the shield. Parco Ut~iUes 8 File No. 98115 NorU3point Business Center Coppell, Texas !GENERAL NOTES-Trench Shields Cont'd. 9.) Shields shall be used such that excavated soil, rock or other debris can not fall or roll into the trench shield. In vertical trenches, the shield should rise a minimum of 1'-6" above the ground surface. In situations where a slope is constructed above the top of the shield, the top of the shield should extend a minimum of 1'- 6" above the point at which the slope begins. In addition, the contractor shall be responsible for removal of soil which may slide into the trench or against the trench shield and for replacing these materials in accordance with backfill specifications. IGENERAL NOTES-Trench Shores 1.) Aluminum Hydraulic Shores are a product designed and manufactured as an alternate to timber shoring in order to provide a light weight product capable of being installed and removed without entering the trench. 2.) Aluminum Hydraulic Shores shall be designed and manufactured so as to comply with OSHA regulations and provide strengths of the vertical rail and hydraulic cross-brace which are not less than a timber bracing system which would be required under the same loading condition. The manufacturer must have complete design calculations on all system components and shall make this information available to the Owner. The following minimum requirements shall be met by the manufacturers' product: a. Vertical rails shall have a minimum width of 8 inches and have an equivalent strength in bending of not less than that of a 3" by 10" No. 2 Douglas Fir timber with its' wide side to the trench wall. The rail must be capable of having plywood attached to it, if necessary. b. The hydraulic cross-braces shall be minimum 2-inch I.D. and capable of sustaining a axial force of not less than 20,000 pounds at al .50 safety factor at 50% extension. c. Aluminum oversleeves shall be used in accordance with the manufacturer's recommendations. Extensions shall not be used unless approved in writing by the manufacturer. d. Hydraulic pumps shall be equipped with calibrated gauge having a minimum operating range of 750-1500 psi. e. All other accessories and specialty tools shall be furnished and used as per the manufacturer's recommendations. 3.) The vertical rails, hydraulic cylinder cross-braces and all other components of the systems shall be in good, serviceable condition and without damage or defects which would prohibit proper use. The hydraulic system, shall not exhibit leaks or pressure loss or otherwise indicate the possible loss of system pressure while in use. Damaged components pr improperly operating equipment shall be removed from service. The contractor's "Competent Person"shall be responsiblb for making these inspections and determinations. Alterations to shoring components shall not be allowed unless permitted in writing by the manufacturer's authorized agent. Parco Utili~..s 9 Nor~point Business Center Rle No. 98115 Coppel/, Texas I GENERAL NOTES-Trench Shores CONT'D , J 4.) Plywood, used in conjunction with hydraulic shores, shall meet the following requirement a. Softwood plywood must be 1 118" minimum thickness, exterior grade quality, CDX grade or better. b. Hardwood plywood must be 3/4", minimum thickness, Arctic Birch plywood. "FinnForm" brand or equal, 14 ply-all hardwood. Plywood which is broken, bent, frayed or otherwise deformed and unsuitable for its intended purpose shall be replaced. 5.) The contractor shall install aluminum hydraulic shores in accordance with these specifications and the manufacturer's specifications, instructions, recommendations and imitations. The recommended shore lengths and spacing are shown in these specifications.The contractor may decrease the spacing to provide additional lateral support if so required by site observations. The contractor's "Competent Person" shall insure that the workmen installing, removing and working around the shoring have been adequately trained in the proper procedures for their installation, safe use and removal. 6.) Hydraulic shores shall be installed flush against the trench walls such that the vertical rails have uniform support. The top hydraulic cylinder must not be located above the existing ground surface. The hydraulic cylinders shall be pressurized to a normal working range of 750-1000 psi. 7.) The contractor may at his discretion utilize shorter rails in order to accommodate those situations such as backfilling where the trench depth becomes to shallow for use of the standard 7-foot vertical rail. The shorter aluminum hydraulic shores must meet or exceed all of the specification requirements herein. 8.) Plywood shall be attached to the vertical rails and used in this manner any time there is evidence of raveling, sloughing or caving which cannot be adequately shored by skip-shoring. In particular, plywood backing will be necessary when shoring cross-trenches, when excavating in previously disturbed soils, and at those locations as indicated in these specifications. 9.) The contractor may at his discretion temporarily remove shoring to expedite the installation of piping provided that workmen are not located in the unshored trench and provided that the shoring is properly replaced. 10.) While backfilling the trench, the contractor shall maintain the stability of the trench walls by adjusting the location of the shores vertically such that workmen can safely place and compact the backfill materials. Workmen shall not be in a position to be endangered by this adjustment procedure. 11 .) The contractor may remove the hydraulic shores from .the trench during backfilling operations provided the following conditions are met: a. Backfilling is performed by mechanical devices which do not.'require that workmen be in the trench. b. The trench walls maintain their shape without sloughing. c. The removal of the hydraulic shores does not endanger adjacent structures, roadways or utilities. Parco U#r~Jes 10 Noclhpoint Business Center Hie No. 98115 Coppel/, Texas SPECIFIC TO THIS WORK ~ 15.0 EXCAVATIONS Location Max. Depth Option(s) Notes Sanitary_ Sewer Line A 0+00 12.0 I or Ila Construct Bore Pit 0+40 12.0 I or Ila Construct Exit Pit Water Line 1 0+00 to 0+65 9.0 I,I] or I!1 Install 8' Water Line 0+65 9.0 I,II or III Install Fire Hydrant 0+65 to 6+88 9.0 I,II or III Install 8" Water Line 6+88 9.0 I,II or III Install Fire Hydrant 6+88 to 9+88 9.0 I,!1 or III Install 8" Water Line 9+88 9.0 I,II or III Install Fire Hydrant 9+88 to 12+88 9.0 I,II or III Install 8" Water Line 12+88 9.0 I,II or III Install Fire Hydrant 12+88 to 15+88 9.0 I,!1 or III Install 8" Water Line 15+88 9.0 I,II or III Install Fire Hydra. nt 15+88 to 18+88 9.0 I,II or III Install 8" Water Line 18+88 9.0 I,II or III Install Fire Hydrant 18+88 to 22+05 9.0 I,II or III Install 8" Water Line 22+05 9.0 I,II or III Install Fire Hydrant 22+05 to 22+14 9.0 I,!1 or III Install 8" SS Water Line at Southside Pro!ect Loc 1 9.0 I,II or III Install 66 LF 6: WL and Fire Hydrant Loc 2 9.0 I,II or III Install 66 LF 6" WL and Fire Hydrant 0+00 tO 8+32 1 1.0 I or II Install 48' RCP 8+32 to 10+32 7.5 I or II Install 42" RCP 10+32 to 11--83 6.0 I or II Install 30" RCP 0+44 10.0 I or II Install Lateral A-1 2+27 10.0 ! or il Install Lateral A-2 4+27 10.0 I or II Install Lateral A-3 6+27 10.0 I or II Install Lateral A-4 8+27 10.0 I or II Install Lateral A-6 0+00 to 11+17 10.0 I or II Install 36" RCP 11+17 to 14+17 7.0 I or II Install 24' RCP 1+67 10.0 i or II Install Lateral B-1 3+01 10.0 I or II Install Lateral B-2 5+12 10.0 I or II Install Lateral B-3 7+12 10.0 I or II Install Lateral B-4 9+12 9.0 I or II Install Lateral B-5 11+12 9.0 I or II Install Lateral B-6 ACTIVE PRESSURE CALCULATION SUMMARY CASE: Patco Utilities Input File = UNTITLED.APR Time: 13:14:31 Date: 01-20-1998 ~ Total active pressure = 3741.26 With angle from horizontal = 0.00 Failure surface from horizontal = 57.10 Total soil weight in failure zone = 5589.48 Total surcharge load in failure zone = 864.47 Soil resistance along failure surface = 7459.91 with angle from horizontal =59.90 Pressure at wall base = 623.54 ~~ Pressure at wall base along horizontal = Pressure at wall base along vertical = coeficient of active pressure Ka = 0.43 The Height of Wall (H) = 12Q_~_~. attered Angle of Wall = 0.00 Friction Angle of Wall = 0.00 Friction Angle of Soil = 27.00 Soil Unit Weight = 120.00 Section Slope Angle Length Of Slope No. (deg) S 1 0 48 Distributed Left Point Left Load Right Point Right Load Load No. Xl Q1 X2 Q2 1 2 14 ~o~ (J4m ~ **************************************************************** Depth Is Measured From Ground Surface ***************************************************************** Force -- lp/ft Pressure -- psf Length -- ft ~I'C~I(P1 LEO sl =111 -~111---' Ref. GENERAL NOTES (4.6.1) I' TRENCHES MORE THAN 5 FEET IN DEPTH SHALL BE NOTES'  ----~ OTHER EQUIVALENT MEANS OF PROTECTION SHALL BE # PROVIDED WHERE EMPLOYEES MAY BE EXPOSED TO ~ MOVING GROUND OR CAVE-INS. TRENCHES LESS THAN 5 FEET IN DEPTH SHAM. ALSO BE J J~ -:[[{ ~ E~F~CT, V~.Y PROTEOTEO WH~. ~X*~N^T,ON ~O~N~,NO,C^TES.~.Z^.~US~ROU.O~OVE~E.~ 1.) HA/ = STEEPEST ALLOWABLE SIDESLOPE Jl~,, ,~,1 HN = .75:1 WEATHERED LIMESTONE .- ' - HN = 1:1 NATURAL CLAY OR SANDY CLAY HN = 1.5:1 EXISTING FILL UNPROTECTED VERTICAL CUT ALLOWED WITH CERTAIN CONDiTiONS, WHEN DEPTH DOES NOT EXCEED 5 FEET. 2.) ALL SLOPES ASSUME DEWATERED SOIL CONDITIONS CONTRACTOR'S "COMPETENT PERSON" TO MONITOR EXCAVATION AND ASSURE THAT THIS PROCEDURE IS SUITABLE. 3.) NO SPOIL OR EQUIPMENT NEARER THAN 2 FEET TO EDGE OF EXCAVATION STANDARD PROVISION 4.) SEE SPECIFICATION - GENERAL NOTES SLOPE ~ FOR ADDITIONAL REQUIREMENTS 2'0" /~- 5.) SLOPE ALL SIDES WHEN PROTECTING STRUCTURE, MANHOLE OR PIT EXCAVATIONS. H~ ~ POlL OR I /~/ STOCKPILED 6.) WHEN "STABLE ROCK" IS ENCOUNTERED, THE ROCK MAY BE EXCAVATED WITH _ ~.5( I/ MATERIAL VERTICAL SIDEWALLS AND SLOPED ABOVE THE ROCK. THE ROCK MUST BE "STABLE" AS DEFINED IN O.S.H.A. 1926. ~ ~1 EXISTING FILL 12' 0" MAX. ~ CLAY OR SANDY CLAY 7.) WHEN CONTRACTOR'S "COMPETENT PERSON" CANNOT BE ASSURED OF THE SOIL TYPE OR SUITABLE SLOPE, A QUALIFIED GEOTECHNICAL  (v) WEATHERED ENGINEER SHALL BE CONSULTED. :~?i .... /0.75 (H) LIMESTONE ORDINARY SLOPE 12' 0" MAX. 2' BENCH ~.CL~Y OR SANDY CLAY Ir~0.7 (v) LIMESTONE Northpoint Business Center 3'6" MAX. Freeport North ~ Coppell, Texas Drawing No. co~,~-~o~ Patco Utilities SLOPE w / UNSUPPORTED BOTTOM D1 MW. Custer, P.E. File No. Date Sca~e iI ~/ STOCKPILED MATERIAL -- '/' STOCKPILED MATERIAL IIII II1~ IIII II!! Illl ~ - MAX. IIII ~ I ~"~" SHIELDS MAY BE b ? SHIELDS MAY BE ~ STACKED AS REQ'D. N .-.~.~.-.~.-~.~. ~ STACKED AS REQ'D. SHIELD MAY SIT ON A 2'~- IMAX ) ~ ~ BENCH IN STIFF C~Y OR ~K" x , ,.-*~ SHIELDBENCH INMAYsTIFFSITONc~yA 2'-0"OR R~K(MAX') SHIELD EXTENDS FROM ~OM ~V~HI~ · '..:...: OF EXCAVATION TO SURFACE ~ TRENCH SHIELD CAPACI~ ~( ~ MINIMUM ~TERAL BEARING CAPACITY. 12.0' 624 PSF 2.) CONT~CTOR SHALL MAKE AVAI~BLE ~NUFACTURER'S TABU~TED DATA ,. ~,.. FOR CAPACITY CERTIFICATION FOR ALL TRENCH SHIELDS USED. '~- C.~'-- ~:,-~ ....c,N~ ~ ..- ,~,~.' ~ 3.) TRENCH SHIELDS MAY BE STACKED AS REQUIRED. '~~ 4.) IN STIFF C~YS OR ~K, THE BOSOM OF THE SHIELD ~Y SIT ON A BENCH ~_. NOT TO EXCEED 2' F~M EXCAVATION BOSOM. 5.) STEEPEST ALLOWABLE SLOPE ABOVE SHIELD 1H: 1V. OPTION II 6.) SEE SPECIFICATION GENERAL NOTES - TRENCH SHIELDS FOR ADD~IONAL REQUIREMENTS TRENCH SHIELD 7.) SHOULD "STABLE R~K" BE ENCOUNTERED, Nodh~int Bu~n~ Center ~E R~K MAYBE EXCAVATED WITH VERTICAL SIDEWALLS AND THE SHIELD ~Y Free~d No~h SIT ABOVE THE"STABLE ~CK". - . ~ppell, Texas 8.) WHEN THE CONTRACTOR'S "COMPETENT PERSON" CANNOT BE ASSURED OF THE SOIL ~PE OR ~,~,~, SUITABLE SHIELD, A QUALIFIED GEOTECHNICAL ENGINEER SHALL BE CONSULTED. Pat~ UtilitiEs 9.) ASSUMED DEWATERED SOIL CONDITIONS - Dra~ No. E~in~ring By: M.W_ Custer, P.E. D2File No. Date ~le 98115 1 ~0~8 None . EXCAVATED OR , ATED OR STOCKPILED J STOCKPILED MATERIAL _,' ,/ MATERIAL < Itt-~ W SHIELDS MAY BE ~ ,/__ :~ STACKED AS ~ ' c~ BE c~ ............. ,., STACKED AS .P~TE ;,~ SHIELD MAY SIT ON A 2'~" SHIELD MAY SIT ON A 2'~)" (MAX.) ~--- ....:.. ~., (MAX.) /- BENCH IN STIFF CLAY OR ROCK Illl :* BENCH IN STIFF CLAY OR ROCK _,.SHIELD EXTENDS FROM BOTTOM TRENOH SHIEED OAP^OITY .,,o_x...o... 1.) USE CHART THIS SHEET TO DETERMINE TRENCH SHIELD - ~ :u. ' ....... MINIMUM LATERAL BEARING CAPACITY. MAX. DEPTH MIN. CAPACITY CONTRACTOR SHALL MAKE AVAiLaBLE MANUFACTURER'S T^BUU TED DATA PIT FOR CAP^crrr CERT~F~CAT,ON FOR ALL TRENCH SHIELDS USED ON TH~S PROJECT. 12.0' 624 PSF 3.) TRENCH SHIELDS MAY BE STACKED AS REQUIRED. OPTION TRENCH SHIELD 4.) IN STIFF CLAYS OR ROCK, THE BOTTOM OF THE SHIELD MAY SIT ON A BENCH NOT TO EXCEED 2' FROM EXCAVATION BOTTOM. - 5.) STEEPEST ALLOWABLE SLOPE ABOVE SHIELD 1H 'lV. PLACE MINIMUM 1" THK. STEEL PLATE Northpoint Business Center BETWEEN THE SHIELD END AND THE PIT 6.) SEE SPECIFICATION GENERAL NOTES - TRENCH SHIELDS FOR FACE SLOPE OR TAIL BACK OF PIT Freeport North ADDITIONAL REQUIREMENTS ' ~, Texas 7.) SHOULD "STABLE ROCK" BE ENCOUNTERED THE ROCK c~,c~ 'Patco Utilities MAYBE EXCAVATED WITH VERTICAL SIDEWALLS AND THE SHIELD MAY BE INSTALLED ABOVE THE "STABLE ROCK" Engineering By: U.W. Custer, P.E.- 8.) WHEN THE CONTRACTOR'S "COMPETENT PERSON" CANNOT BE ASSURED OF THE SOIL Drawing No. File No. Date Scale TYPE OR SUITABLE SHIELD,A QUALIFIED GEOTECHNICAI ENGINEER SHALL BE CONSULTED. D3 98115 1/20/98 None [~r -.. TRENCHBy; SHORES AS MANUFACTURED c~ i "Speed-Shore"T"" ,,, ~ ..~ ,,Tren_Shore,,T- o TYPICAL "Safe-T-Shore" ~: ~< ALUMINUM STANDARDHYDRAU~DuTY-TRENCH SHORE or Equal ~ ~ SEE GENERAL NOTES "TRENCH SHORES" FOR ~ ~ ADDITIONAL REQUIREMENTS TYPICAL ALUMINUM HYDRAULIC TRENCH SHORE INSTAL~TION OPTION III  TRENCH SHORES /// ...... Nodhpoint Busings Center TYP~AL Free~d No~h ALUMINUM HYDRA~ TRENCH SHORE Coppell, Texas STANDA~ D~Y- W / PLYW~ BACKING ~'=~ Patco Utilities E~in~dng By: PLYW~D ~1~ REQUIRED WHEN TH~ ~ EVI~NCE OF Dra~ No. RAVELLING ~ CAVING File No. Date S~le 4 98115 1~0~8 No~