MATERIAL SPECIFICATION FOR CLAY SEAL

Transcription

1 ONTARIO PROVINCIAL STANDARD SPECIFICATION METRIC OPSS.MUNI 1205 APRIL 2015 MATERIAL SPECIFICATION FOR CLAY SEAL TABLE OF CONTENTS SCOPE REFERENCES DEFINITIONS DESIGN AND SUBMISSION REQUIREMENTS MATERIALS EQUIPMENT - Not Used PRODUCTION - Not Used QUALITY ASSURANCE OWNER PURCHASE OF MATERIAL - Not Used APPENDICES 1205-A Commentary SCOPE This specification covers the requirements of clay seal material for use at the inlet side of culverts and in pipe trenches Specification Significance and Use This specification is written as a municipal-oriented specification. Municipal-oriented specifications are developed to reflect the administration, testing, and payment policies, procedures, and practices of many municipalities in Ontario. Use of this specification or any other specification shall be according to the Contract Documents. Page 1 Rev. Date: 04/2015 OPSS.MUNI 1205

2 Appendices Significance and Use Appendices are not for use in provincial contracts as they are developed for municipal use, and then, only when invoked by the Owner. Appendices are developed for the Owner s use only. Inclusion of an appendix as part of the Contract Documents is solely at the discretion of the Owner. Appendices are not a mandatory part of this specification and only become part of the Contract Documents as the Owner invokes them. Invoking a particular appendix does not obligate an Owner to use all available appendices. Only invoked appendices form part of the Contract Documents. The decision to use any appendix is determined by an Owner after considering their contract requirements and their administrative, payment, and testing procedures, policies, and practices. Depending on these considerations, an Owner may not wish to invoke some or any of the available appendices REFERENCES When the Contract Documents indicate that municipal-oriented specifications are to be used and there is a municipal-oriented specification of the same number as those listed below, references within this specification to an OPSS shall be deemed to mean OPSS.MUNI, unless use of a provincial-oriented specification is specified in the Contract Documents. When there is not a corresponding municipaloriented specification, the references below shall be considered to be the OPSS listed, unless use of a provincial-oriented specification is specified in the Contract Documents. This specification refers to the following standards, specifications, or publications: Ontario Provincial Standard Specifications, Material OPSS 1010 Aggregates - Base, Subbase, Select Subgrade, and Backfill Material ASTM International D Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter DEFINITIONS For the purpose of this specification, the following definitions apply: Bentonite means a commercial term applied to clay deposits containing sodium montmorillonite as the essential mineral. Clay means a fine textured (i.e., grain size smaller than mm) sedimentary or residual deposit consisting of hydrated silicates of aluminum mixed with various impurities, but no organics. It is a cohesive and plastic soil within a wide range of water content. Geosynthetic Clay Liner means sodium bentonite clay sandwiched between two protective geotextiles. Liquid Limit means the water content between the semi-liquid and the plastic states of the soil. Page 2 Rev. Date: 04/2015 OPSS.MUNI 1205

3 Plastic Limit means the water content between the plastic and semi-solid states of the soil. Plasticity Index means the water content range of a soil at which it is plastic, defined numerically as the liquid limit minus the plastic limit DESIGN AND SUBMISSION REQUIREMENTS Submission Requirements Samples of natural clay material proposed for use in clay seal shall be submitted to the Contract Administrator for approval 3 weeks prior to use. When clay mixture is proposed for use, a minimum 25 kg sample of the Granular A and a minimum 7 kg sample of Bentonite shall be submitted to the Contract Administrator 3 weeks prior to use. The clay mixture shall be left to cure at various moisture contents for a minimum period of 24 hours prior to performing standard Proctor density tests and flexible wall permeability tests on samples compacted to 95% of its standard Proctor maximum dry density MATERIAL General Material used for clay seals shall lie within the hatched area shown in Figure 1 and shall be natural clay or clay mixture. Alternatively, a geosynthetic clay liner as specified in the Geosynthetic Clay Liner subsection may be used. The coefficient of permeability as determined in the flexible wall permeameter according to ASTM D 5084 shall not exceed 1 x 10-6 cm/s Natural Clay Clay material for clay seal shall be according to the following: a) Liquid limit shall be > 40%. b) Plasticity index shall be > 0.73 x (Liquid Limit - 20%) Clay Mixture Alternatively, material for clay seal may be made of the following mixture by volume: a) 1 part Bentonite powder b) 3.5 parts Granular A The mixing of the material shall be carried out in an approved mechanical mixer. At placement, the moisture content of the mixture shall be maintained to within 1% of the optimum moisture content. Page 3 Rev. Date: 04/2015 OPSS.MUNI 1205

4 Geosynthetic Clay Liner Material specifications containing the physical, mechanical, and hydraulic properties of the geosynthetic clay liner shall be obtained from the manufacturer. The material specification shall include a manufacturer s certification and warranty. Installation shall be as per manufacturer s instructions Granular A Granular A shall be according to OPSS QUALITY ASSURANCE Sampling and Testing Sampling requirements of clay seal material (e.g., sampling location, intervals, and lot sizes) shall be as specified in the Contract Documents. The Contract Administrator may elect to carry out testing at the quality assurance laboratory to ensure that clay seal material used in the work conform to the requirements of this specification. Page 4 Rev. Date: 04/2015 OPSS.MUNI 1205

5 FIGURE 1 Plasticity Chart NOTES: A. Figure 1, Plasticity Chart, originates from early principle soil classification developed by Arthur Casagrande and further enhanced by the Unified Soil Classification System. B. Figure 1 is used to distinguish between different fine grained soil types. Only highly plastic clays that fall within the limits of Figure 1 are specified as suitable clay seal materials in this specification. Page 5 Rev. Date: 04/2015 OPSS.MUNI 1205

6 Appendix 1205-A, April 2015 FOR USE WHILE DESIGNING MUNICIPAL CONTRACTS Note: This is a non-mandatory Commentary Appendix intended to provide information to a designer, during the design stage of a contract, on the use of the OPS specification in a municipal contract. This appendix does not form part of the standard specification. Actions and considerations discussed in this appendix are for information purposes only and do not supersede an Owner s design decisions and methodology. Designer Action/Considerations The designer should specify the following in the Contract Documents: - Sampling requirements of clay seal material. ( ) The designer should ensure that the General Conditions of Contract and the 100 Series General Specifications are included in the Contract Documents. Related Ontario Provincial Standard Drawings OPSD Clay Seal for Pipe Trenches Page 6 Rev. Date: 04/2015 OPSS.MUNI 1205