6-12 Sectio N 602 – Masonry
602.0 1 DESCRIPTION . This work shall consist of furnishing material s and constructing walls and other masonry of the types and sizes specified ; or rebuilding, repairing, or repointing existing masonry ; or coring into an existing concrete structure and mortaring pipe, ducts, or conduit (collectively termed pipe in this section) into the structure . 602.0 2 MATERIALS . Materials shall meet the requirements of the following subsection s: Granular Backfill for Structures ................................ ................................ ................. 704.08 Stone for Masonry ................................ ................................ ................................ ......706.01 Stone for Masonry Facing ................................ ................................ .......................... 706.02 Mortar, Type II ................................ ................................ ................................ ........... 707.0 1(c) Mortar, Type IV ................................ ................................ ................................ ......... 707.0 1(e) Mortar, Type V ................................ ................................ ................................ .......... 707.01(f) Mortar, Type VI ................................ ................................ ................................ ......... 707.01(g) Bar Reinforcement ................................ ................................ ................................ .....713.01 Materials used for rebuilding or repairing stone masonry shall be approved by the Engineer prior to use . New s tone, as required, shall match as closely as practical the existing stone masonry color, texture, and size. If required to match the existing stone masonry, chemical treatment processes to aid in providing stone of similar color shall be investigated by th e Contractor. Mortar used in stone masonry and repointing stone masonry shall be Type II, Type V, or Type VI mortar as specified in the Contract. Concrete for headwalls shall meet the requirements of Section 541 for Concrete, Class B. Dowels shall be in accordance with the requirements of Subsection 713.01(a) , unless other wise specified on the Plans. 602.0 3 MIXIN G OF MORTAR . The fine aggregate and cement shall be mixed in a clean, tight container until a mixture of uniform color is produced, after which clean water shall be added in such quantity as to form a mortar with t he consistency of stiff paste . If desired, the Contractor will be permitted to use a batch mixer of an approved size and type . Mortar which has been mixed for more than 45 minutes shall not be used, and re -tempering of mortar will not be permitted. 602.0 4 PLACIN G OF STONE . The placing and shaping of stone shall be the same for dry or cement masonry , however, dry masonry shall be placed without the use of mortar.
6-13 The bed shall be clean and well moistened just prior to the placement of the stone. The ston e shall be
thoroughly saturated with water, well bedded into the mortar , and carefully settled in place before the mortar has set . No spalls will be permitted in the bed. Joints and beds shall not average over 1 inch in thickness. The masonry shall be laid in full mortar beds to the lines shown on the Plans and in approximately level courses. The bottom or foundation courses shall be composed of large , selected stones. All courses shall be laid with bearing beds parallel to the natural bed of the material s. The larger stone shall be used near the bottom and the smaller stone near the top of the masonry, the latter corresponding, as nearly as possible, to the minimum thickness of the masonry at its top. The construction of stone masonry will not be permitted in freezing weather or when frost is in the stone, except by written permission of the Engineer and subject to conditions as the Engineer may require. In walls where the thickness is over 4 feet, the stones used as headers for holding in the heart of the wall shall extend not less than 4 feet into the core and shall occupy not less than 20% of the front and back surface area of the wall. In walls where the thickness is 4 feet or less, the stones used as headers shall extend entirely through the wall. The b reak in joints of the stone shall be at least 6 inches on the exposed faces of the wall and the backing stones shall be laid so that the joints are broken . The rear face of the wall shall present an approximately plane surface. The stone shall be roughly s quared on joints, beds, and faces, and shall be pitched to line, at all angles and ends of walls . All shaping or dressing of stones shall be done before the stone is laid in the wall, and no dressing or hammering that would tend to loosen the stones alread y set will be permitted after their placement . Any stone around which the bond has become broken shall be removed, the mortar shall be thoroughly cleaned from the bed and joints, and the stone shall be reset in fresh mortar. 602.0 5 WEEP HOLES . Weep holes shall be constructed as shown on the Plans or as ordered by the Engineer. 602.0 6 REBUIL T STON E MASONR Y AND REPAIRIN G STON E MASONRY .
a.General Requirements .
1.Rebuilt Stone Masonry . The stone masonry of the existing substructure and wingwalls shall be mapped, removed, and rebuilt as indicated and specified in the Contract .
6-14 Following backfill excavation, the existing stones, tree stumps, roots, and other foreign
matter shall be removed in the areas shown on the Plans or where d irected by the Engineer . The existing stones shall be reset in their original locations, removing any gaps that occurred due to previous damage to the walls . Rebuilt stone masonry shall match securely into adjacent masonry.
2.Repairing Stone Masonry . Earth, minor vegetation, and other foreign matter shall be removed and cavities in the stone substructure and wingwalls filled as indicated and specified in the Contract .
b.Construction Requirements .
1.Rebuilt Stone Masonry . The work shall be performed by a stone mason who is highly knowledgeable and experienced in the construction of dry stone masonry walls and fascia . The Contractor’s stone mason performing the work must demonstrate at least five years of experience in the construction of dry stone mason ry walls . Documentation of experience, including a list of previous project s and references, shall be submitted to the Engineer prior to commencement of the work . The existing stone masonry in the areas of reconstruction shall be mapped out and documented . Each stone’s size and location shall be noted . The Contractor, prior to stone removal, shall submit documentation to the Engineer for approval. Special care and precautions shall be taken during removal and storage of the existing stone masonry to ensure that the stone is not damaged. All stones shall be carefully removed in the areas shown on the Plans . The Contractor shall shore the remaining portions of the walls to ensure that they do not shift during construction. The existing stones shall be replaced in their original locations, removing any gaps that occurred due to previous damage to the walls . All joints in the reconstructed stone walls shall be no larger than 3/4 inch between stones . Any existing stones that are not suitable for replacement or that are missing shall be replaced by the Contractor with stones of similar size and appearance.
2.Repairing Stone Masonry .
a.Examination . The Contractor and Engineer shall jointly examine the abutments and wingwalls to field verify the extent of the work . All work shall be performed by stonemasons with a minimum of three years of experience with similar work .
6-15 b. Repair . Gaps between horizontal faces of existing stones less than 1 inch shall n ot
be repaired . The size of these gaps shall equal the approximate diameter of a 7/8- inch steel dowel. Gaps between horizontal faces of existing stones between 1 inch and 6 inches shall have small stone blocks added, with the depth of the blocks as large a s possible for good bearing . The minimum width of said blocks shall be 4 inches. Gaps between horizontal faces of existing stones greater than 6 inches shall have crushed gravel and stone blocks added . The crushed gravel shall be placed at the back of the stone and compacted in place up to 12 inches of the exposed wall face . The crushed gravel shall be compacted by tamping rods or other methods acceptable to the Engineer . Stone blocks shall then be added to achieve a tight fit . New stone blocks shall not ex tend beyond the face of the stone wall. 602.0 7 POINTIN G AND REPOINTING . All joints shall be filled with mortar, well driven in, and finished with an approved pointing tool for a distance of 1/2 inch back from the surface of the stone. When joints are in old masonry, they shall be cleaned of all loose mortar and dirt for a dept h in from the face of the wall of at least twice the width of the joint and moistened. All mortar shall be cleaned from the face of the stones after the pointing is completed and the work has cured for a period of three days. 602.0 8 CORIN G CONCRETE . The existing concrete structure shall be cored to allow the new pipe to extend into or through the structure. The diameter of the core shall be between 1/2 inch and 1 -1/2 inches larger than the diameter of the installed pipe. The pipe shall be mortared in place using Type II mortar , filling any voids between the pipe and the structure. 602.0 9 DOWEL S AND TIES. Where required, bonding of various portions of the work shall be accomplished with dowels and ties of the shapes and dimensions shown on the Plans or approved by the Engineer . They shall be placed, as shown or required, in the stone so as to clear the bed of the succeeding course. Dowel holes shall be drilled into each stone, to match dowels already set, before the stone is placed . No drilled holes will be permitted in the exposed top surfaces.
6-16 602.10 BACKFILLING . Spaces excavated for masonry structure s, but not occupied by these structures,
shall be backfilled . The backfill shall be placed in horizontal layers of not more than 6 inches in depth . Each layer shall be thoroughly compacted by means of air or mechanical tampers in a manner approved by the E ngineer. 602.1 1 METHO D OF MEASUREMENT . The quantities of Cement Masonry and Dry Masonry to be measured for payment will be the number of cubic yards used in the complete and accepted work , measured in accordance with the dimensions shown on the Plans or o rdered by the Engineer. The quantity of Stone Masonry Facing to be measured for payment will be the number of square yards in the complete and accepted work, measured as the height of the front face plus the width of the capstones times the length of the stone masonry facing . No deductions will be made for weep hole s, drain pipes, or other openings with an area of less than 2 square feet. The quantity of Repointing Masonry to be measured for payment will be the number of square yards in the complete and accepted work, measured as the total surface area of the masonry repointed. The quantity of Rebuilt Stone Masonry to be measured for payment will be the number of cubic yards of stone masonry rebuilt in the complete and accepted work , measured in accordance with the dimensions shown on the Plans or as determined by the Engineer. The quantity of Repairing Stone Masonry to be measured for payment will be the number of square yards of stone masonry repaired in the complete and accepted work , measured as the total surface area of the repaired masonry. The quantity of Coring Concrete to be measured for payment will be the number of each core made in the complete and accepted work. 602.1 2 BASIS OF PAYMENT . The accepted quantities of Cement Masonry, Dry Masonry, Stone Masonry Facing, and Repointing Masonry will be paid for at the Contract unit price per cubic yard or square yard for the item specified . Payment will be full compensation for furnishing, transporting, handling, and placing the material specified and for furnishing all labor, tools, equipment , and incidental s necessary to complete the work . The dowels and ties required for constructing stone masonry facing will not be paid for separately but will be considered incidental to the Contract unit price per square yard for Stone Masonry Facing. Excavation will be paid for as Trench Excavation, unle ss otherwise shown on the Plans.
6-17 The accepted quantity of Rebuilt Stone Masonry will be paid for at the Contract unit price per cubic yard .
Payment will be full compensation for mapping, documenting, and removing existing stone masonry; furnishing new s tone as needed; furnishing, transporting, handling, and placing the material s specified; backfilling when not paid under a separate Contract item ; and for furnishing all labor, tools, equipment , and incidentals necessary to complete the work . Excavation ad jacent to Rebuilt Stone Masonry and disposal of excess or unsuitable excavated material will be paid for at the Contract unit price per cubic yard for Structure Excavation . Excavation shall be backfilled with material acceptable to the Engineer . When Granu lar Backfill for Structures is required for backfill material , it will be paid for at the Contract unit price per cubic yard. The accepted quantity of Repairing Stone Masonry will be paid for at the Contract unit price per square yard. Payment will be full compensation for removing material specified from the face of stone masonry; filling cavities; furnishing, transporting, handling, and placing the material s specified; and for furnishing all labor, tools, equipment , and incidentals necessary to complete t he work . The accepted quantity of Coring Concrete will be paid for at the Contract unit price per each. Payment will be full compensation for coring the existing concrete structure, for mortaring new pipe in place, and for furnishing all labor, materials, tools, equipment, and incidentals necessary to complete the work. New pipe will be paid for under the appropriate Contract items. Excavation, including backfill operations and the disposal of excavated material (excess or unsuitable for backfill), will be paid under the appropriate Contract excavation items. Payment will be made under: Pay Item Pay Unit 602.15 00 Cement Mas onry ................................ ................................ ....................... Cubic Yard 602.20 00 Dry Masonry ................................ ................................ ............................. Cubic Yard 602.25 00 Stone Masonry Facing ................................ ................................ .............. Square Yard 602.30 00 Repointing Masonry ................................ ................................ .................. Square Yard 602.35 00 Rebuilt Stone Masonry ................................ ................................ ............. Cubic Yard 602.40 00 Repairing Stone Masonry ................................ ................................ ......... Square Yard 602.4500 Coring Concrete ................................ ................................ ........................ Each
6-18 Sectio N 604 – Drop Inlets , Catc H Basins , and Manholes
604.0 1 DESCRIPTION . This work shall consist of the construction, rehabilitation, adjustment, or decommissioning of drop inlets (DIs) , catch basins, and manholes , and the furnishing and placing of cast iron or precast concrete covers. 604.0 2 MATERIALS . Materi als shall meet the requirements of the following subsection s: Granular Backfill for Structures ................................ ................................ ................. 704.08 Manhole Brick ................................ ................................ ................................ ........... 705.01( a) Concrete Masonry Blocks ................................ ................................ .......................... 705.02 Precast Drop Inlets, Catch Basins, and Manholes ................................ ..................... 705.0 3 Mortar, Type II ................................ ................................ ................................ ........... 707.0 1(c) Mortar, Type IV ................................ ................................ ................................ ......... 707.0 1(e) Reinforced Concrete Pipe ................................ ................................ .......................... 710.01 Bar Reinforcement ................................ ................................ ................................ .....713.01 Welded Wire Reinforcement ................................ ................................ ..................... 713.0 3 Structural Steel ................................ ................................ ................................ ........... 714.02 Gray Iron Castings ................................ ................................ ................................ .....715.01(b) Ductile Iron Castings ................................ ................................ ................................ .715.01(c) Treated Timber Curb ................................ ................................ ................................ ..729.05 Unless otherwise specified, cast -in-place co ncrete shall conform to the requirements of Section 541 for Concrete, Class B. Flowable fill shall conform to the requirements of Section 541 for Flowable Fill, Excavatable . Pipe stubs for precast reinforced concrete curb drop inlets shall meet the requirements of Section 601 . The term cast iron, as used in these specification s, or in the names of various pay items, when used in conjunction with covers and frames, shall be und erstood to mean gray iron castings or ductile iron castings. Covers and frames shall be gray iron castings or ductile iron castings. Steps or ladder rungs in drop inlets, catch basins, or manholes shall be plastic, complying with all applicable OSHA dimens ional and structural requirements . Unless otherwise shown on the Plans, the rungs shall be cast into the fresh concrete, except that for precast units, the rungs may be grouted into preformed voids with a non -shrink grout approved by the Engineer after the concrete has cured.
Source: Vermont Standard Specifications for Construction, 2024 Edition. Pages 786–791 of 1,380.