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Forest Cove 2-SP 980326F£ TRENCH SAFETY SPECIFICATIONS FOR ~REST COVE ESTATES PHASE 2 CITY OF COPPELL, TEXAS Prepared for SITE CONCRETE, INC. TREN- TECH COMPANY 828 HOWELL DR. COPPELL, TEXAS 75019 9 72-304-2171 I have reviewed these Trench Safety Guidelines and find that the recommendations and procedures conform to OSHA guidelines and regulations. The calculations herein are consistent with generally accepted engineering practice. REGISTERED PROFESSIONAL ENGINEER DATE Entire contents copyright © 1993 by TrenITech Company. ,41l rights reserved. 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 General. These specifications cover the basic requirements for shoring and/or sloping of excavations for the installation of SANITARY SEWER LINES, WATERLINES and STORM SEWER LINES for the FOREST COVE ESTATES, PHASE 2 in the CITY of COPPELL, TEXAS. 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. 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. The personnel protection systems shown in these specifications have been designed based on information obtained from the project drawings and specifications. In accordance with Revised OSHA (Appendix A to Subpart P effective March 2,1990), the Contractor's "Competent Person" will conduct the required Soil Classification Tests. If soils other than those previously 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. Contractor shall be responsible for selecting the appropriate safety system option shown in these specifications, depending on trench depth and soil conditions. The protection of existing structures and utilities which may be affected by these trench excavations is beyOnd the scope of this report (See Sect.4.2) The Contractor mgst identify a "Competent Person" in the Contractor's firm responsible for performing inspections of the excavations to ensure that expected subsurface conditions are preCent. NOTE-This person must be "Competent" as described in OSHA 1926.650(b). 1 It is the Contracto are within the regt (including death) negligence in pea these specification fs responsibility to ensure that all excavation work and site conditions tlations as established by OSHA. Any property damage or bodily injury arising from the use of these specifications, from the Contractors ,rmance of contract work, or from Owner's failure to note exceptions to shall remain the sole responsibility and liability of the contractor. Copyright © 1993 by Tren-Tech Company 2.1 2.2 2.3 2.4 All definitons of section 1926.653 of Subpart P, Part 1926, of the Code of Federal ReI ulations shall be by reference an integral part of this section. / "Sealing l~agineer"- The engineer whose Texas seal is affixed to these specifications. "The Contt described "Compete actor"-The contractor responsible to the owner for the excavation work erein. t" as described in OSHA 1926.650(b). 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.1.6 3.1.7 3.1.8 3.2 OccupatioJ AISC Code AISC Spec AITC Timt AWS DI.1 The Unifor OSHA 222 U S Army The latest in effect ol codes and The Contr}ctor shall perform all shoring work under this contract in accordance with all ~pplicable codes and standard safety requirements and regulations including:l OSHA 22( 7, Construction Industry Standards (Part 1926, tal Safety and Health Standards) of Standard Practice. .fications of the design, fabrication, and erection of steel buildings ,er Construction Manual Structural Welding Code m Building Code 5 2orps of Engineers EM 385-1-1 ~dition (including supplements and revisions) of the above publications .promulgated at the time of the bid shall apply. Equipment fabricated to standards in effect at time of bid but later revised shall be acceptable provided s ach revisions are not required by law. 2 Copyright © 1993 by Tren-Tech Company 4.1 4.2 4.3 Description This section Existing St~ Where exis in close pr, trenching o sheeting ax covers the technical requirements of the trenching/shoring work. -uctures. ting buildings, other utilities, streets, highways, or other structures are )ximity to the trench, or may otherwise be affected by the proposed peration, the Contractor shall provide adequate protection by the use of .d shoring to protect the structure, street, or highway from possible damage. Ip the case of utilities, the Contractor may elect to remove the utility, provided tl)at the removal and subsequent replacement meet with the approval of the engineqr, the utility owner, or whoever has jurisdiction of the structure. In all cases, it sh~ll be the responsibility of the Contractor to protect public and private property told any person or persons who might, as a result of the Contractor's work, be in ured. General Tr The Contrac applicable Safety and Federal Re to the requi 4.3.1 Th~ 192 pa~ ~nching and Shoring Requirements· tor shall be solely responsible for trench safety provisions meeting the requirements of the United States Department of Labor-Occupational Health Administration, including subpart P, Part 1926, of the Code of ;ulations. All trenching operations and procedure shall also conform :ements listed in this specification. requirements of sections 1926.650 and 1926.651 of Subpart P, Part 6, of the Code of Federal Regulations shall be by reference an integral ~ of this section. 4.4.1 4.4.2 1 Known undergroumd installations are shown on the site plans. It is the Contractor's responsibility to vlrify exact locations in the field. ,B, efore any indivfdual enters an excavation, the excavatmn will be inspected by a Competent Persqn to ensure that trench excavation has been performed according to this specification and OSHA requirements and to ensure that no anomalies are observed which may effect lhe safety of the trench project. Note-This person must be "Competent" as described in O~HA 1926.650(b). 3 Copyright © 1993 by Tren-Tech Company 4.5.1 4.5. 4.5.3 4.5.4 4.5.5 4.5.6 4.5.7 4.5.8 4.5.9 4.5.10 4.5.11 During excavatiot determined by the be provided so as ~ Daily inspections I evidence of possit necessary precauti trench. Note-This Excavations shall occurrence to ensu Excavated materia the trench stabilit3 a minimum to pro' be no closer than All precautions excavation. Ade~ Operation of hca The Contractor is loads imposed on The Contractor m to excessive dryin Water shall not b adequate capacity The Contractor si not build up behir If a condition rel specification will Remove shoring When backfill is unless the trench t, the exact location of existing underground installations shall be Contractor, and when uncovered, proper precautions and supports shall tot to cause a hazard to the workmen or the project. if the excavations shall be made by the Competent Person". If there is .lc cave-ins or slides, all work in the excavation shall cease until the ~ns have been taken to ensure the safety of the workmen and the person must be "Competent" as described in OSHA 1926.650. be inspected after every rainstorm or other hazard-increasing e safety of the workmen and the trench. shall be stockpiled a distance away from the trench, so as not to affect The Contractor's means and methods will determine the distance. As :ct the workmen from falling debris, the toe of the stockpiled soil shall ~vo(2) feet from the edge of the excavation. nust be made to prevent surface water from entering the trench xate drainage must be provided in the area adjacent to the excavation. y equipment adjacent to the edge of the trench may cause instability. responsible for the means and methods of excavation, and therefore, for he trench excavation and shoring design. tst take precautions to protect the face of the excavation from exposure g, water, or freezing. : permitted to stand in the bottom of the trench and suction pumps of shall be installed to ensure that such standing water is removed. .all provide a positive means of ensuring that hydrostatic pressure does d the shoring or shields. airing the use of a different method of shoring is encountered, this ,e revised. mits from bottom to top as backfilling proceeds. a4thin five(5) feet of the top of the trench, all shoring may be removed, :onditions indicate a hazard. 4 Copyright © 1993 by Tren-Tech Company 4.5.12 No person shall 1: removed. 4.5.13 Additional shoring 4.5.14 Ladders or other a~ more than twenty-: 4.5.15 When two(2) tren¢ that the depth of ti e exposed to the lower portion of the trench after shoring has been of larger sizes may be installed. lequate means of exit must be provided and located so as to require no 5ve(25) feet of lateral travel. hes intersect, both trenches must be protected to a distance of not less ~e deepest trench. 4.6.1 4.6.2 4.6.3 4.6.4 4.6.5 Prior to constmcti excavations that (i.e. landfills, man During constructic the contractor sha atmospheres in all less than 19.5 pel shall be deemed 3n the contractor shall identify any areas near the proposed )uld expose workmen to harmful levels of atmospheric contaminants holes or materials storage). n, before workmen are allowed in an excavation or existing structure, 11 test the air quality at these previously identified areas for hazardous excavations greater than four (4) feet in depth. Atmospheres containing 'cent oxygen or more than 20 percent concentration of flammable gas ~azardous" adequate precautions shall be taken. Retesting of wor[ areas shall be conducted as often as necessary to ensure that the atmosphere remains safe for workmen. During constmctlon, emergency rescue equipment shall be readily available where potentially hazard ~us conditions are expected to develop. As a minimum, t Breathing appara! in potentially haz~ xe contractor shall have on site the following emergency equipment. us, a safety harness and line, or a basket stretcher. During construction rdous areas, the required equipment shall be attended. 5 Copyright © 1993 by Tren-Tech Company SECTION 5.0 SITE SPECIFIC EXCAVATIONS AND Si~ORING SPECIFICATIONS FOR I ~¢ANITARY SEWER LINES WATER LINES AND ; STORM SEWER I 6 Copyright © 1993 by Tren-Tech Company SANITARY SEWER LI~E "D" LOCATION ~. DEPTH 1+14.00 TO 1+82.00 1+82.00 1+82.00 TO 3+72.00 3+72.00 3+72.00 TO 6+37.00 6+37.00 6+37.00 TO 9+70.00 9+70.00 9+70.00 TO 14+00.00 14+00.00 7.0 8.0 7.5 8.5 10.0 11.0 10.0 9.0 8.0 7.0 / SANITARY SEWER L~E "E" 1 LOCATION I MM. DEPTH 0+92.00 TO 6+10.00 6+10.00 6+10.00 TO 8+25.00 8+25.00 SANITARY SEWER LOCATION 1+00.00 TO 6+20.00 6+20.00 6+20.00 TO 7+80.00 9.0 8.0 6.0 7.0 NE "F" MM. DEPTH 9.0 10.0 9.0 OPTION I, II, III I, II I, II, III I, II I, II, III I, II I, II, III I, II I, II, III I, II OPTION I, II, III I, II I, II, III I, II OPTION I, II, IH I, II I, II, III 7 Copyright © 1993 by Tren-Tech Company NOTES 1NSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. CONST. MANHOLE NOTES INSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. CONST. MANHOLE NOTES INSTALL 8" S.S. CONST. MANHOLE INSTALL 8" S.S. SANITARY SEWER LE~E "G" LOCATION 1+00.00 TO 1+65.94 1+65.94 1+65.94 TO 3+45.95 STORM SEWER LINE" LOCATION 1+05 TO 2+30 STORM SEWER LINE LOCATION 1+00.00 TO 1+55.00 STORM SEWER LINE LOCATION 1+00 TO 1+57 STORM SEWER LINE LOCATION 3+90 TO 4+60 PROJECT LATERALS The contractor shall use referenced storm drain li related piping. MAX. DEPTH OPTION NOTES 7.0 I, II, III INSTALL 8" S.S. 7.0 I, II CONST. MANHOLE 7.5 I, II, III INSTALL 8" S.S. MAX. DEPTH OPTION NOTES 6.0 I, II, III INSTALL 21" RCP MAX. DEPTH OPTION NOTES 5.0 I, II, III INSTALL 21" RCP CH MAX. DEPTH OPTION NOTES 4.0 I, II, III INSTALL 18" RCP MAX. DEPTH OPTION NOTES 5.0 I, II, III INSTALL 18" RCP t INLETS uidelines set forth in Option I for the construction of inlets on the above .es and use guidelines set forth in Option I or II for the installation of 8 Copyright © 1993 by Tren-Tech Company PROJECT WATERLINEI AND APPURTENANCES The contractor is requirec~ to install various water lines on the project. No profiles for these I ' ' x avation various waterlines were p[ovided on the project plans, however, it is doubtful that e c depths greater than five flet will be necessary and therefore shoring may not be required. If excavation depths greater than five feet are encountered or if there is evidence of raveling or caving for any reason including pre-disturbed soil conditions, the contractor will be required to shore or slope the excavalion so as to provide a safe workplace. The contractor may use guidelines set forth in Op!ion I, II or III for these excavations. 9 Copyright © 1993 by Tren-Tech Company 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 Trenches more the other equivalent n to moving groum effectivety protect, may be expected. The Contractor wi Lateral Earth Pres~, Assumed Soil: C] P= a uniformly disl~ We= Effective Soil H= Depth of excav~ bottom of exca~ Hq= Equivalent Hei[ Reference OSHA Rul as amended by the xt five(5) deep shall be shored, laid back to a stable slope, or some teans of protection shall be provided where employees may be exposed or cave-ins. Trenches less than five(5)feet in depth shall also be 'd when examination of ground indicates hazardous ground movement 11 have Options I, II or III for providing such protection. ure: P = We(H+Hq) ibuted lateral soil pressure, in lbs./l~2 reight, pcf(Use 45 psfType"B" Soil) lion from top of supported bank to ation in feet. ht of Surcharge, in feet. es and Regulations-Part 1926 of 29 CFR Federal Register Volume 54, Number 209, Hq T~ WE 45 H October 31, 1989 1 Maximum anticipated lateral earth Option I The specification. A method. Vertical restrictions may paved street areas Option II The 12 this specification shield(s) and or pressure for this project is 585 "PSF" Contractor can use Slope as shown in the Option I section of the pplicable slopes may be obtained by either straight cut or benched cuts for the benched method shall not exceed four(4) feet. Easement imit the use of this option. Option I is normally not permissible in See Drawing Option I. ontractor may use a Trench Shield as shown in the Option II section of Requirements set forth in this Option shall include curricular trench manhole boxes. All slopes above trench shield(s) shall conform to guidelines set for,th in Option I. carry a minimum "tabulated data" Option II. Option III The this specificatio~ determined by th Option III. If tl~ behind the shore~, Trench shield(s) used on this project will be required to "PSF" as specified. Certification of trench shield(s) or manufacture's shall be available for verification during construction. See Drawing 2ontractor can use Trench Shores as shown in the Option III Section of t. Shores are to be installed as shown with horizontal spacing e depth of cut and soil type but shall not exceed 6 feet. See Drawing ere is raveling of the trench wall, the contractor shall install plywood as shown on the Option III drawing. 10 Copyright © 1993 by Tren-Tech Company TRENCH SA FE TY SPE CIFICA TIONS OPTION I SLOPE 3~o Siw:dglt sBl~n;c~ ia} __~l l~l The contractor may use t~ benched method of"slophe'e'. H/V ~ REQUIRED SLOPE PER SOIL TYPE I-I/V = ~4 to 1 H/V itol H/V = ~½ tol H/V=~ tol Stiff clay less than 12 feet in depth (Type "A") Stiff clay or weathered limestone (Type "A" or "B") Silty clays or saturated material (Type "C") Fill material or loose soil. NOTES 1. All trenches shall be dewatered as specified in 4.5.7 2. All slopes assume sufl icient right-of-way exists. 3. All slopes shall be flaltened an additional ½ foot if an existing parallel utility line is located within the ho< zontal distance equal to the depth of the new utility excavation. 4. No spoil or cquipmenl shall be permitted nearer than 2 feet from the edge of the excavation. 5. A single 3' 6" vertical bench may be used in "stiff clay" only. 6. Exposed existing utilil y lines are to be supported. 11 Copyright © 1993 by Tren-Tech Company TRENCH SA FE TY SPE CIFICA TIONS TRENCH SHIELD Spoil :avation shall f the trench guidelines Sloped portions of the ex~ begin 18" below the top c shield(s) and conform to set forth in Option I. Trench shield(s) may be b~ in "stiff clay". :nched 2 feet I Requirements and methods stipulated herein will apply to "manhole boxes" and/or "circular shields" that have been manufactured for personnel protection. NOTES 1. Trench shields shall be insp.~cted and be fi'ee of structural defects that may impair their proper function. 2. Trench shields shall be usec in accordance with the manufacturer's guidelines and recommendations. 3. Trench shields shall be inst~ lied so as to prevent any lateral or other hazardous movement. 4. Personnel shall not be allo~ ed in the trench shield during its installation or removal from the excavation. 5. When shield(s) are stacked the upper shield shall be rated for its physical depth in the trench. 6. Trench shield(s) used on this project shall be rated to withstand anticipated "PSF" (left side of graph) for depth of cut indicated below. Manufacture's tabulated data or certification shall be maintained on site. 600 550 5O0 450 40O 350 300 5 Feet 7.5 Feet 12 Copyright © 1993 by Tren-Tech Company 11 Feet TR E NCoptiTi ONSA FETY SPE CIFI CA TI 0 NS III Plywood installed behind shores to prevent raveling. 4. Aluminum hydraulic shorin 5. Maximum horizontal spacir 6. Maximum horizontal spacir 7. The contractor's competent 8. The hydraulic shores shall [ 9. The contractor shall adhere 10. If there is evidence of ravel 14 ply arctic white birch (Fi~ 11. Spoil material will not be a NOTES / 1. Shores shall be double stacked when trench depths exceed nine (9) feet. 2. Maximum horizontal spac~g for double stacked shores shall be five (5) feet. 3. Maximum allowable depth 9fcut for this Option shall be fourteen (14) feet. ; may be used in Type "A" or "B" soils only. g of shores in Type "A" soil shall be 6 feet. g of shores in Type "B" soil shall be 5 feet. person shall inspect shores and verify that they are in good working order. ave a minimum working pressure of 750 psi. to the shoring manufacturer's guidelines for use in trench excavations. ing or caving the contractor is required to install 1 I/8" thick plywood or 3A" thick nland form). [lowed nearer than 2' from the edge of the excavation 13 Copyright © 1993 by Tren-Tech Company