PART E SPECIFICATIONS

Transcription

1 PART E SPECIFICATIONS

2 Page 1 of 5 PART E - SPECIFICATIONS GENERAL E1. APPLICABLE SPECIFICATIONS, STANDARD DETAILS AND DRAWINGS E1.1 The City of Winnipeg Works and Operations Division Standard Construction in its entirety, whether or not specifically listed on Form B: Prices, shall apply to the Work. E1.1.1 E1.1.2 Division 2 - Standard Provisions, Provision CW 1100 of The City of Winnipeg Works and Operations Division Standard Construction shall apply to the Work. Further to GC:2.4(d), included in the Tender Package shall govern over The City of Winnipeg Works and Operations Division Standard Construction. E1.2 The following Drawings are applicable to the Work: Drawing No. S1 S2 S3 S4 S5 Drawing Plan West Elevation East Elevation North & South Elevation Tyndal Stone Repair Detail E2. PART 1 GENERAL SECTION E2.1 Provide all labour, materials, methods, equipment, accessories and supervision required for the completion of the Tyndal Stone repairs. This shall include, but is not necessarily limited to the following: (a) Review all elevations and remove all loose stone. (b) Supply and install stainless steel strapping preformed to appropriate shape and together with the required anchors, Anchoring Type A, Section (c) Supply and installation of anchors c/w caulking, Anchoring Type B, Section 04407, to seal the holes complete with pull tests as specified. (d) Removal of loose fractured segments of stone-panels on a square foot basis Section E3. GENERAL REQUIREMENTS E3.1 The Contractor shall provide barricades with solid planked roof at and under each swing stage location. Barricades to be full width of sidewalk and located so that a minimum of 6 lineal feet of barricade extend beyond each end of the swing stage. Pedestrians access to be through the barricade under the roof. E3.2 When moving the swing stage, the Contractor must ensure that the area is properly fenced and/or hoarded. All hoarding must be stable and secure under all conditions. E3.3 The Contractor will not close off any public sidewalk or deny the public access to the building. E4. STANDARDS E4.1 Comply with National Building Code, Part 8, Construction Safety Measures at Construction and Demolition Sites, Provincial requirements and local authorities having jurisdiction.

3 Page 2 of 5 E5. EXISTING CONDITIONS E5.1 Existing condition of building will be its condition at time of examination prior to tender. E6. PROTECTION E6.1 Take precautions to support affected stonework and, if safety of working conditions or public or staff access could be compromised, supply and install appropriate shoring or protection devices. E6.2 Execute all Work in an orderly, careful manner with due consideration for the occupants of the building. E6.3 Cooperate with City staff and general public. Allow for uninterrupted passage, and access for such persons while repair Work in progress. Provide covered walkways, hoardings, etc. as required or as directed by the Contract Administrator. E6.4 Limit and/or phase all drillings, repairs and operations to suit City requirements. City requested Work hours, suspensions or accelerations shall incur no penalty, financial or otherwise to the City. E7. PART 2 PRODUCTS MATERIAL REMOVAL E7.1 All limestone areas and surfaces on all 4 elevations will be visually examined for loose material, which will be removed. E7.2 The Contractor will exhibit appropriate care, being aware that stone material may become dislodged during the examination and repair process. E7.3 Where a removed piece of stone exposes a joint that is uncaulked or unsealed, the Contractor will supply and install appropriate and required caulking and/or sealing to prevent the penetration of environmental moisture into the wall system. E8. ANCHORING E8.1 Drilling required for anchor installation will be preformed only by experienced workmen and care will be taken to control the use of and the dripping or coursing of the water-based slurry down the face of the building. E8.2 The installation of the caulking in the hole will be left flush with the surrounding stone. In cold weather, the caulking will be kept in suitable heated containers until just before installation. E8.3 This installation process with the drilling may induce further incipient cracking requiring further anchoring. Confirm with the site Contract Administrators Representative prior to installation of further anchors. E9. STRAPPING E9.1 At locations where strapping is required, Contractor will take detailed measurements including angles suitable to fabricate the strap off site. E9.2 After prefabrication, a separate swing-stage set-up will be required to install the strapping. E9.3 Care shall be taken with any drilling operations required for anchoring the straps.

4 Page 3 of 5 E10. LOCATION E10.1 The Contract Administrators Representative will locate each and every anchor and/or strapping. Following installation of the anchors, the Contract Administrator reserves the right to complete an additional pass on the swing-stage with the Contractor to confirm the anchor installation. E10.2 The Contractor will meet with the Contract Administrator prior to the start of repairs to formulate swing stage size, installation and procedures to define the wing stage pattern for each of the four elevations. E10.3 On site, the Contractor will provide swing stage operators and access to the Contract Administrators Representative on pre-notice of 24 hours. E10.4 The Contract Administrators Representative will also be responsible to determine quantities of extra Work as may be required and will apply the Unit Rates as applicable and in conjunction with the Contract Administrator review the Contract Price as may be required. E11. LIGHT FIXTURES E11.1 Wall fixtures to be removed and reinstalled. Contractor will be responsible for any and all damage. E12. CLEANING E12.1 The Contractor shall remove, legally dispose off site daily, when directed, all removed material, debris, waste, etc., except if directed to turn over to City. E12.2 The Contractor shall refer to Clause E8 and follow requirements to daily clean all drilling site and spillage of any slurry material. Drips and tracks on the face to the building will not be allowed. E13. PART 2 GENERAL - SECTION E13.1 Cracking and debonding in select stones has progressed to the extent that a program of interim stabilization is required. The identification and stabilization of such areas is required to reduce the possibility of the stone falling away from the building. A remediation program has been previously completed, however this follow-up program shall identify and stabilize additional areas of loose or debonded stone. (a) Design Considerations (i) The Tyndal stone cladding has a nominal thickness of 1.5", bonded to a precast concrete panel approximately 3.5" thick. This section therefore details temporary anchoring of the stone panels to the structural backup in areas required, as determined on-site. (ii) Small, shallow stone spalls less than 0.5 square feet in size which are visibly loose or fractured to the point in which the section is fully debonded from the substrate are to be removed by the Contractor. Removal of these loose fractures is to be included into the swing-stage mobilization and operational fixed price. (iii) This specification shall be read in conjunction with attached repair Drawing S-5. (b) Work Included (i) Select locations at the discretion of the Contract Administrators Representative will have an in-situ load test to establish the integrity of typical panel anchorages. (ii) This specification section presents two individual procedures for the masonry stabilization.

5 Page 4 of 5 Method A: Method B: Method C: Anchoring steel panels over stone, secured into the concrete precast backup. Installing through-stone anchors to reinforce existing anchorage. Removal of loose fractured segments of stone panels on a square foot basis, anchoring the perimeter and weather sealing the stone/concrete interface with Dow 790 Sealant. E14. PRODUCTS E14.1 Anchors used to reinforce existing stone cladding panel anchorage to be 10 mm Helifix stainless steel wall ties, manufactured and supplied by Helifix North America Corporation, 110 Maplecrete Road, Concord, ON, Phone: E14.2 Anchors to secure steel panels and stone to be Hilti 304 or 316 stainless steel 10 mm Kwik Bolt II's, available from Hilti, 120 Bannister Road, Winnipeg, MB, Phone: E14.3 Stainless steel short strapping to be Type 302 stainless or better, with a thickness of not less than 16 gauge. E15. EXECUTION (a) REPAIR TYPE A: Anchoring of stainless steel strapping to secure large areas of stone. (i) At areas designated for 16 gauge Type 302 or better stainless steel strapping, 10 mm stainless steel Hilti Kwik Bolt II anchors, complete with 1" diameter stainless steel washer and Hex nut are to be utilized to secure the metal panel to the concrete precast back up. (ii) Using an electric drill, drill a 12 mm hole through the stone and 2" into the precast concrete structural backup. Use non-hammer setting when drilling through the stone only. Ensure new anchors are a minimum of 4" from existing pins. (iii) Supply and install Hilti 10 mm anchors through stone, and set 2" into concrete backup. Anchors to be 304 or 316 stainless steel complete with stainless steel plate washer and hex nut. (iv) Ensure anchors are torqued to manufacturer's specifications. (b) REPAIR TYPE B: Reinforcement of existing in-situ panels using Helifix anchors. (i) The anchors have been based on a minimum capacity of 250 pounds in both tension and shear. At panels designated for reinforcement, one anchor shall be installed for every 2.5 square feet of stone area, but panels designated for reinforcement measuring 1 square foot or larger shall have a minimum of two (2) anchors installed. (ii) Pre-drill a 8 mm entry hole into the Tyndal stone and precast concrete backup to a depth of 3" into the concrete. The hole must be of sufficient depth so that the anchor head will be recessed below the stone surface by 0.25". The hole shall be drilled at 30º above the horizontal. Confirm that drill hole diameter is in accordance with manufacturer's specifications for anchors to be utilized. (iii) Connect insertion tool assembly to a high speed hammer drill to drive Helifix 10 mm anchor through the Tyndal stone into the concrete until the end of the tie is recessed a minimum 1/4" below face of the Tyndal stone. (iv) Patch outer face of stone in accordance with specifications using Dow Corning 790 so that anchor location is concealed. (c) REPAIR TYPE C: Removal of localized areas of stone exhibiting significant fracturing. (i) Using a grinder, cut a fracture plane around the perimeter of the unsound area designated for removal by the structural Contractor.

6 Page 5 of 5 (ii) (iii) (iv) Using a cold chisel or electric chipping hammer, remove the Tyndal stone (only) from the unsound area, leaving the underlying concrete unscathed. Install Helifix anchors, one per side per square foot of stone removal. Example, if the stone removal is two foot by two foot, install two Helifix anchors per side of opening. Weather seal stone/concrete interface with cant strip of Dow Corning 790 Sealant. E16. TESTING E16.1 Tensile Testing of Hilti Anchors (a) The Contract Administrators Representative shall have a manufacturer's representative complete no less than five (5) load tests on the specified anchor in the existing substrate prior to commencement of masonry repairs. The average minimum level of tensile resistance required is 500 pounds with no single test less than 400 pounds. All costs associated with testing shall be carried by the Contractor and/or manufacturer. E16.2 Load Testing Helifix Anchors (a) At five (5) locations designated by the Contract Administrators Representative, the Contractor shall predrill holes and insert 10 mm Helifix anchors, in accordance with manufacturer's specifications and as specified herein, to a depth of 1.25" into the stone and not into the backup. Five (5) additional tests shall then be completed with the 10 mm anchor installed 3" into the concrete structural backup. (b) The anchor manufacturer, Helifix North America Corporation, has an in-situ, nondestructive load testing device. The Contractor shall be responsible for obtaining and renting this load test device from the manufacturer. All costs associated with the unit rental shall be carried by the Contractor and/or manufacturer. (c) The tensile load test shall be carried out by the Contractor in accordance with the manufacturer's specifications. Results to be verified by the Contract Administrator. Anchor design is based on average ultimate capacity of not less than 250 pounds both in tension and shear. If results are less than 250 pounds, the anchor spacing will be decreased.