807Masonry Construction

— MASONRY CONSTRUCTION

807.01DESCRIPTION

This work includes the construction of masonry structures and masonry portions of composite structures of various types at the required locations. Ensure that the work complies with the currently adopted editions of the AASHTO LRFD Bridge Construction Specifications , the AASHTO Historic Bridge Preservation Guide, and SECTION 939. Cut Stone Masonry (Ashlar). Use c ut stone masonry or masonry veneer that is dressed and tooled to the required fixed dimensions and laid in range or random courses in a cement mortar bed. Split Face Masonry. Use s plit face masonry or veneer that is composed of quarry stone laid in range or random courses in a cement mortar bed and set substantially level. Use materials that include coping, quoin, and belt stones shaped to line and grade. Splay a reasonable proportion of the joints from the vertical as indicated. Split faced masonry may include a fascia wall one stone thick backed with concrete or constructed of solid stone masonry. Rubble Masonry. Use rubble masonry that is composed of irregular stones laid as coursed or uncoursed rubble in a cement mortar bed. Rubble masonry may include either a fascia wall one stone thick backed with concrete or constructed of solid stone masonry. Dry Rubble Masonry. Use dry rubble masonry that is composed of irregular stones laid as coursed or uncoursed rubble without the use of cement mortar. Concrete Block or Brick Masonry. Use concrete block and brick masonry that includes concrete blocks or brick laid in cement mortar and may be unreinforced or reinforced with steel reinforcing. Block or brick pavements and catch basin/manhole masonry construction/repairs are not included under this designation.

807.02MATERIALS

Stone. Use stone that conforms to SECTION M14.

Part 800 — Bridge Structures August 2025

Block and Brick.

meet the requirements of ASTM C90. Protect concrete block units from rain, snow, or other moisture during storage on or off the job site to ensure that the units will meet the Type I moisture requirements at the time they are placed.

Brick (solid masonry units made from clay or shale) (ASTM C62), Concrete Building Brick (ASTM C55), or Load-Bearing Concrete Masonry Units (ASTM C90). Use bricks that have a fine-grained, uniform, and dense structure, free from lumps of lime, laminations, cracks, checks, soluble salts, or other defects that may impair their strength, durability, appearance, or usefulness. Ensure that bricks emit a clear, metallic ring when struck with a hammer. Mortar. Use mortar that conforms to Subsection M04.03.5. Lead, Dowels, and Cramps. Use leaded joints, wrought iron, and galvanized or stainless steel dowels or cramps that conform to SECTION M05. Concrete. Use c oncrete backing of stone fascia walls that is Class A . Use concrete that conforms to SECTION 601. Reinforcing Steel. Use reinforcing steel that conforms to Subsection M05.02. Grout. Use grout for filling voids in hollow masonry units that conforms to ASTM C476.

807.03CONSTRUCTION METHODS

Weather Limitations. Do not constructs tone, brick, or block masonry using mortar or grout when the atmospheric or surface temperature is below 40° F, when the respective units contain frost, or when the temperature is expected to drop below 40°F within 24 hours of placement, except with the written permission of the Engineer subject to any required conditions . Remove and replace all work damaged by cold weather at no additional cost to the Department. In hot or dry weather, protect

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800-46SECTION 807 — MASONRY CONSTRUCTION

the masonry from the sun, and cure by keeping the masonry or its covering wet for a period of three days after completion. Mixing of Mortar and Grout. Proportion the mortar and grout for masonry construction as specified in Subsections 807.02.3 and 807.02.7. Either hand or machine mix the mortar, as required by the Engineer. In the preparation of hand- mixed mortar, thoroughly mix the sand and cement together in a clean, tight mortar box until the mixture has uniform color. Add sufficient clean water to form a stiff plastic mass. Prepare the mortar mix for not less than three minutes nor more than 10 minutes. Do not mix the mortar on the roadway surface. Add sufficient water to provide a mortar consistency that can be handled easily and spread with a trowel. Ensure that the water is fresh, clean water, which is not used from a stormwater conveyance system. Mix mortar and/or grout only in those quantities required for immediate use. Discard m ortar not used within 45 minutes after water has been added or before initial set begins, whichever occurs first. Stone Masonry Construction.

weaken or prevent the stone from proper embedment. Provide a shape to meet the requirements for the class of masonry specified. • Furnish stones in the sizes and face areas necessary to produce the required characteristics and appearance. • Ensure that the thickness of courses, if varied, diminish regularly from bottom to top of wall. • Use header lengths that are not less than the width of bed of the widest adjacent stretcher plus 12 in.

• Size. Use individual stones that have a thickness of not less than 8 in. and a width of not less than 1½ times the thickness. Do not use stones, except headers, that have a length less than 1½ times their width. • S hape. Use stones that are roughly squared on joints, beds, and faces. Use selected stone, roughly squared and pitched to line, at all angles and ends of walls. If specified, finish all corners or angles in exterior surfaces with a chisel draft.

Part 800 — Bridge Structures August 2025

• Bed Surface. Ensure that bed surfaces of face stones are normal to the faces of the stones for approximately 3 in. F rom this point, ensure that surfaces depart from normal not more than 2 in. in 12 in. Provide joint surfaces of face stones that form an angle with the bed surfaces of not less than 45 degrees. • Laying Stone in Wall . Perform all shaping or dressing of stone before the stone is laid in the wall. Do not allow dressing or hammering to loosen the stone after it is placed. • Dr essing . Dress the stone to remove any thin or weak portions. Dress face stones to provide bed and joint lines with a maximum variation from true line of 1½ in. • Other . Construct rubble masonry and dry rubble masonry according to the applicable requirements of SECTION 911 and SECTION 912.

• Size. Use individual stones that are large and well proportioned. Provide stones that are not less than 12 in. nor more than 30 in. in thickness. • Dr essing . Dress stones to the exact sizes and shapes before being laid. Cut the stones to lie on their natural beds with top and bottom truly parallel. Do not use hollow beds. Ensure that t he bottom bed is the full size of the stone and that no stone has an overhanging top. In rock-face construction, ensure that the face side of any stone does not present an undercut contour adjacent to its bottom arris that yields a top-heavy, unstable appearance when laid. Fine finish the beds of face stone for a depth of not less than 12 in. Fine finish the vertical joints of face stone , which must be full to the square for a depth of not less than 9 in. Provide exposed surfaces of the face stone with edges pitched to true lines and exact batter. C ut chisel drafts 1½ -in. wide at all exterior corners. Rough finish face stone forming the starling or nosing of piers. Do not allow holes for stone hooks to be visible in exposed surfaces. • Stretchers. Use stretchers that have a width of bed of not less than 1½ times their thickness. Ensure that the stretchers have a length of bed not less than twice nor more than 3½ times their thickness and not less than 3 ft.

angles to the front faces of the stones. Dress the surfaces for a distance of at least 3 in. from the front faces and the soffits, from which points they may depart from a plane normal to the face not to exceed ¾ in. to 12 in. Ensure that the back surface in contact with the concrete of the arch barrel is parallel to the front face and is dressed for 6 in. from the intrados. Cut the top perpendicular to the front face, and dress the top for a distance of at least 3 in. from the front.

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When concrete will be placed after the masonry has been constructed, ensure that the adjacent ring stones vary at least 6 in. in depth. Ensure that the stratification in arch ring stones is parallel to the radial joints and, in other stones, is parallel to the beds. Lay out a full -size template of the arch ring near the quarry site, showing face dimensions of each ring stone and thickness of joints. The Engineer will the template before the shaping of any ring stone is started . Do not place the ring stone in the structure until all ring stones have been shaped, dressed, and approved by the Engineer.

is firm and normal to, or in steps normal to, the face of the wall, and approved by the Engineer before any stone is placed. When it is placed on foundation masonry, clean the bearing surface of the foundation masonry and ensure that the surface is in a saturated-surface dry condition when the mortar bed is spread. Set face stones in a random bond to produce the required effect. Prevent the bunching of small stones or stones of the same size. When weathered or colored stones or stones of varying texture are being used, distribute the various kinds of stones uniformly throughout the exposed faces of the work. Use large stones for the bottom courses and use large, selected stones in the corners. In general, ensure that the stones decrease in size from the bottom to the top of work. Clean and saturate each stone with water before being set. Ensure that the bed that will receive the stone is clean and well moistened. Bed all stones securely in freshly made mortar. Ensure that t he mortar joints are full and the stones settled in place before the mortar has set. Any spalls in the beds will result in rejection. Do not pin up any stones with spalls in beds. Do not drop any s tones on or slide them over the wall. Do not hammer, roll, or turn the stones on the wall. Set the stones without jarring the stone already laid, and handle with an appliance that will not cause disfigurement. If any stone is moved or the joint broken, remove the stone, clean the mortar from the bed and joints, and reset the stone in fresh mortar.

the bottom or foundation courses, use large, selected stones and lay all courses with bearing beds parallel to the natural bed of the material. Ensure that the vertical joints in each course of rubble masonry break with those in adjoining courses at least 6 in . Do not locate a vertical joint directly above or below a header.

shlar Masonry . For all range cut stone masonry , lay the stone with alternating stretchers and headers. Place stones in any one course of ashlar masonry to form bonds of not less than 12 in. with the stones of adjoining courses. Place headers over

Part 800 — Bridge Structures August 2025

stretchers and, in general, ensure that the headers of each course equally divide the spaces between the headers of adjoining courses. Do not place a header over a joint, and do not install a joint over a header.

line, at all angles, wall expansion and contraction joints, and other arr ises. Dress copings and belt stones for the required jointing, and pitch exposed corners parallel to each other. Ensure that exposed surfaces have projections of not more than 1 in. Cut the bed and interior ends normal to the pitch lines.

wall not less than 5 ft high and 8 ft long, showing examples of the face wall and method of forming joints. The Engineer must approve the sample section before the start of wall facing. If approved, the sample section may be incorporated into the final product, subject to final inspection and acceptance.

for split face masonry to exceed 1 in.; and face joints for rubble masonry to exceed 1½ in. Ensure that t he joints in the interior of the wall average not more than 1½ in. for rubble masonry. The thickness or beds in ashlar masonry may vary as shown from the bottom to the top of the work. However, in each course, ensure that the beds have a uniform thickness throughout. Do not allow beds to extend in an unbroken line through more than five stones. Provide vertical joints in ashlar masonry. In all other masonry, joints may be at angles with the vertical from 0 degrees to 45 degrees. Ensure that each face stone bonds with all contiguous face stones at least 6 in. longitudinally and 2 in. vertically. Ensure that ring stone joints on the faces and soffits are not less than ¾ in. nor more than 1½ in. in thickness. Provide level c ross beds for vertical walls . B attered walls may vary from level to normal to the batter line of the face of the wall. Fill all joints with mortar.

When practical, point face joints before the mortar sets. Prepare joints that cannot be immediately pointed for pointing by raking the joints out to a depth of 2 in. before the mortar has set. Ensure that the stone face surfaces are not smeared with any mortar. Wet joints not pointed at the time the stone is laid with clean water and fill with mortar. Ensure that the mortar is driven into the joints and finished with an approved pointing tool. Slightly crown the mortar in joints on top surfaces at the center of the masonry to provide drainage. Ensure that walls remain wet while pointing is being performed.

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800-50SECTION 807 — MASONRY CONSTRUCTION

In hot or dry weather, protect the pointed masonry from the sun and keep the walls wet for at least three days after completion. After the pointing is completed and the mortar set, thoroughly clean the wall.

face and that they extend not less than 12 in. into the core. Ensure that headers occupy not less than one-fifth of the face area of the wall and are evenly distributed. Provide headers in walls 3 ft or less in thickness that extend entirely through the wall. Place headers in ashlar masonry in each course that has a width of not less than 1½ times their thickness. In walls having a thickness of 4 ft or less, extend the headers entirely through the wall. In walls of greater thickness, provide a length of headers that is not less than 2½ times their thickness when the course is 18 in. or less in height and not less than 4 ft in courses of greater height. Space the headers not further apart than 8 ft center to center. Provide at least one header to every two stretchers.

interlocked stones including headers and stretchers or of concrete. Provide headers and stretchers in walls that have a thickness of 3 ft or less that have a width or length equal to the full thickness of the wall. Do not use backing or core.

stone is the same size and character as the face stone and that the remaining stones have sizes and shapes that facilitate proper interlocking with face stones. Ensure that all courses are less than 8 in. thick. Lay stone backing in the same manner as specified for face stone, with headers interlocking with face headers when the thickness of the wall permits. Lay backing to break joints with the face stone. Lay stone cores in full mortar beds to bond not less than 12 in. with face and backing stone and with each other. Ensure that bed joints in cores and backing do not exceed 1 in. in thickness and that vertical joints do not exceed 2 in. in width.

ensure that all spaces around the stones are filled and that provide full contact and efficient bond with all stone surfaces.

approximately level with the face course before the succeeding course is started.

backing, install the back of the masonry as unevenly as the stones permit.

Part 800 — Bridge Structures August 2025

After the stone facing has been laid and the mortar has attained sufficient strength, clean all surfaces against which concrete will be placed, and remove all dirt, loose material, and accumulations of mortar droppings. When placing concrete , fill all interstices of the masonry , and spade and work the concrete until it has tight contact with every part of the back of the masonry. Place horizontal construction joints in the concrete backing at grades that will break joints of the stone facing. Provide concrete courses that are approximately 4 ft in depth.

abutments, and stone in piers with wrought iron, galvanized steel, or stainless steel cramps or dowels. Drill dowel holes that will be covered by stone masonry through each stone before the stone is placed and, after it is in place, extend the dowel holes by drilling into the underlying course not less than 6 in. On stones where it is desirable to avoid drill holes through the top surfaces, conceal by setting and grouting the stones over dowels set in the preceding course or by a similar method. Inset cramps or dowels in the stone to clear the bed of the succeeding course. Locate the cramps or dowels to securely bond the stone courses together and the stone facing to the concrete backing. Set cramps and dowels in lead to completely fill the surrounding spaces with the molten metal. Otherwise, rigidly anchor the cramps or dowels by other means approved by the Engineer.

bridge seats. On piers, do not use more than two stones to provide the entire width of coping. Use copings at abutment bridge seats that have sufficient width to extend at least 4 in. under the backwall. Form each step of the coping of a wingwall with a single stone that overlaps the stone forming the step immediately below at least 12 in. For tops of copings, provide a bevel cut at least 2 in. wide, and fine finish the beds, bevel cuts, and tops. Smooth finish the vertical joints, and lay the copings with joints not more than ¼ in. thick. Provide a drip bead to the underside of projecting copings. Locate joints in copings to provide not less than a 12-in. bond with the stones of the under course and to ensure that no joint will come directly under the superstructure masonry plates.

after placement and while the mortar is fresh. Ensure that the stones remain clean until the work is completed. After the pointing is completed and the mortar set, clean the wall.

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800-52SECTION 807 — MASONRY CONSTRUCTION

Brick or Block Masonry.

the “shove-joint” method; do not use “buttered” or plastered joints. Saturate surface dry with water a ll clay or shale brick before placement. D o not dampen concrete masonry units before or during construction, unless approved by the Engineer. Arrange the headers and stretchers to bond the mass , and proceed with alternate headers and stretchers with consecutive courses breaking joints. Fill all joints with mortar. Provide joints that are not less than ¼ in. and not more than ⅝ in. in thickness. Ensure that the thickness is uniform throughout. Finish all joints as the work progresses and, on exposed faces, neatly strike the joints using the weather joint. Do not use any spalls or bats except for shaping around irregular openings or when unavoidable to finish out a course . When used, place full bricks at the corners, placing the bats in the interior of the course. Adjust each masonry unit to its final position while the mortar is still soft and plastic. Remove units that are disturbed after the mortar has stiffened and relay in fresh mortar. Align vertical cells to be filled with grout to provide a continuous unobstructed opening. Piers and walls may be built of solid brick work or may include a brick or block shell backed with concrete.

position at the top and bottom and at intermediate points not exceeding 200 bar diameters or 10 ft apart. Ensure that bars are clear of the cell walls and within ±½ in. of their planned position transverse to the wall and within ±2 in. of their planned position longitudinal to the wall.

the masonry act together as a structural element. Before grouting, clean the grout space so that all spaces to be filled with grout do not contain mortar projections greater than ½ in., mortar droppings, or other foreign material. Place grout so that all spaces to be grouted do not contain voids. Control grout materials and water content to provide adequate fluidity for placement without segregation. Ensure that size and height limitations of the grout space or cell on average are not less than the values in the Table below. The Engineer may approve the use of higher grout pours or smaller cavity widths or cell sizes than shown in the Table below, if it is demonstrated that grout spaces are properly filled. When required by the Table, provide cleanouts in the bottom course at every vertical bar but not be spaced more than 32 in. on center for solidly grouted masonry. Ensure that cleanouts have sufficient size to allow removal of debris.

Part 800 — Bridge Structures August 2025

Grouting Limitations Grout Type Grout Pour Maximum Height (ft) Width of Grout Space (in.)2 Cell Dimensions (in. × in.) Cleanout Required3 Fine 1 ¾ 1½ × 2 No Fine 5 1½ 1½ × 2 No Fine 8 1½ 1½ × 3 Yes Fine 12 1½ 1¾ × 3 Yes Fine 24 2 3 × 3 Yes Coarse 1 1½ 1½ × 3 No Coarse 5 2 2½ × 3 No Coarse 8 2 3 × 3 Yes Coarse 12 2½ 3 × 3 Yes Coarse 24 3 3 × 4 Yes Notes: 1 The clear dimension is the cell or group space width less mortar projections. 2 Increase grout space width by the horizontal projection of the diameters of the horizontal bars within the cross section of the grout space. 3 Cleanouts may be omitted if approved provisions are made to keep the grout space clean before grouting. Units may be laid to the full height of the grout pour . Place grout in a continuous pour in grout lifts not exceeding 6 ft. If construction joints are used in columns of grout, locate the joints at least 1½ in. below the level of a mortar bed joint. Avoid segregation of the grout materials and damage to the masonry during the grouting process. Consolidate the grout before loss of plasticity to fill the grout space. Mechanically reconsolidate grout pours greater than 12 in. in height to minimize voids due to water loss. Puddle any grout not mechanically vibrated. In nonstructural elements, mortar that is of pouring consistency may be substituted for grout when the masonry is constructed and grouted in pours of 12 in. or less. Vertical barriers of masonry may be built across the grout space. Complete the grouting of any section of wall between barriers in one day with no interruption longer than one hour.

807.04METHOD OF MEASUREMENT

Stone Masonry. Stone masonry will be measured by the number of square feet of exposed wall surface placed.

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800-54SECTION 807 — MASONRY CONSTRUCTION

Pointing and Grouting. When listed as a separate item in the Contract , Pointing and Grouting will be measured by the number of linear feet of wall installed. When not listed in the Contract , Pointing and Grouting is incidental and not measured for payment. Concrete Block and Brick Masonry. Concrete Block Masonry and/or Brick Masonry will be measured by the number of square feet placed in the structure. Concrete Backing. Concrete Backing of stone fascia walls will be measured by the number of cubic yards placed.

807.05BASIS OF PAYMENT

The Department will pay for the completed and accepted quantities as follows. Pay Item Pay Unit Stone Masonry SF Pointing and Grouting LF Concrete Block Masonry and/or Brick Masonry SF Concrete Backing CY Payment at the Contract unit price is full compensation for all resources, labor, materials, equipment, and incidentals required to finish the work, complete and accepted. Stone masonry sample wall sections, when required, are incidental and not paid separately.