ICC Structural Masonry Inspector (Exam 84) flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

TMS 402 vs TMS 602

TMS 402 is the design standard for masonry structures using allowable stress or strength design. TMS 602 covers construction and inspection requirements, including materials, workmanship, tolerances, grouting, and inspection levels.

Specified compressive strength f'm

The compressive strength of the masonry assembly assumed in design, established by prism testing per ASTM C1314 or by TMS 402 unit-strength tables. It is not the strength of an individual unit and must match the drawings.

ASTM C90 unit strength

Concrete masonry units must have a minimum net-area compressive strength of 1900 psi for individual units and a three-unit average of at least 2000 psi, along with absorption and moisture content limits.

Brick weathering grades

ASTM C216 and C652 assign grades SW for severe weathering, MW for moderate, and NW for negligible exposure. The specified grade must match the project's exposure condition shown on the drawings.

Mortar type compressive strengths

ASTM C270 mortar types have minimum 28-day strengths: type M 2500 psi, S 1800 psi, N 750 psi, O 350 psi. Type is selected by the designer and cannot be substituted without written approval.

Fine versus coarse grout

ASTM C476 fine grout is used for clear grout spaces of 1/4 to 1/2 inch. Coarse grout is used where the clear space exceeds 1/2 inch. Both require slump of 8 to 11 inches at placement.

ASD unity equation

Allowable stress design checks computed service-level axial and bending stresses against allowable values, including a combined unity equation for axial plus bending in TMS 402.

Strength design resistance factors

Strength design applies factored loads and resistance factors, typically 0.90 for reinforcement in tension and 0.60 to 0.80 for masonry compression, depending on failure mode and inspection level.

Development length and lap splices

Reinforcement development length depends on bar size, yield strength, f'm, cover, and tension or compression. Lap splices must be at least the development length unless the drawings specify otherwise.

Special inspection effect on phi

Some strength-design cases permit a higher resistance factor when special inspection is provided. If the design relies on that increase, the inspector's presence and documentation are structural requirements.

IBC Chapter 21 adoption

The International Building Code adopts TMS 402 and TMS 602 by reference in Chapter 21. Local amendments may change inspection thresholds, so verify the edition in force for the project.

ASTM C780 mortar testing

ASTM C780 governs field sampling and testing of mortar, including compressive strength, water retention, and air content. It specifies sampling frequency, specimen preparation, and curing requirements.

ASTM C1019 grout testing

ASTM C1019 governs sampling and testing of grout using prisms built from the same units and grout as the work, cured under conditions matching the wall.

ASTM C1314 prism testing

Prism testing establishes f'm for the project. Prisms must be built from the same units, mortar, and grout used in the work and cured under the same conditions as the wall.

Inspection plan hold points

Hold points are stages where work must stop for inspection and release, including material verification, first-course layout, reinforcement before grouting, grout placement, and final acceptance.

Plan review checklist

Before construction, verify unit type and grade, mortar type, grout strength, reinforcement size, spacing and cover, wall ties, flashing, and the specified inspection level against the contract documents.

Nonconformance report contents

A nonconformance report describes the deviation, the affected location, the proposed disposition, and the designer's written approval. Work must not be covered until the report is closed.

Daily inspection report

The daily report records weather, ambient temperature, materials delivered, work performed, tests taken, instructions given, and the release of each hold point.

Mortar proportion by volume

ASTM C270 volume proportions of cement to lime to sand are type M 1:1/4:3, type S 1:1/2:4, type N 1:1:6, and type O 1:2:9.

Mortar mixing and retempering

Mortar must be mechanically mixed at least 3 to 5 minutes. Stiffened mortar must not be retempered after initial set, and mortar mixed more than 2.5 hours must be discarded.

Mortar cube testing

Mortar compressive strength is tested on 2-inch cubes molded per ASTM C780 and tested at 28 days, with results compared to the ASTM C270 requirement for the specified mortar type.

Grout slump at placement

Grout per ASTM C476 must have a slump of 8 to 11 inches measured at the point of placement and must be placed within 1.5 hours of mixing. Do not add water to restore slump.

Vertical bar cover

Cover is measured from the bar surface to the exposed face of the masonry. Vertical reinforcement must be placed in the cells shown on the drawings with the specified cover.

Joint reinforcement lap

Joint reinforcement is placed in the mortar joint and must be lapped at least 6 inches at splices unless the drawings specify otherwise. It must be embedded in full mortar.

Anchor bolt embedment

Anchor bolts and embedded plates must be set to the template dimensions with the specified embedment depth and projection, verified against the drawings before grouting.

Wall tie spacing

Wall ties are typically spaced 16 inches on center horizontally and vertically for cavity walls, with additional ties at openings and edges, per the drawings and TMS 602.

Joint thickness tolerance

Bed and head joints are nominally 3/8 inch, permitted from 1/4 to 1/2 inch. Joint thickness must be within plus or minus 1/8 inch of the specified thickness.

Plumb and level tolerances

TMS 602 requires masonry plumb within 1/4 inch per 10 feet and 1/2 inch in 20 feet, level within 1/4 inch per 10 feet, and wall alignment within 1/4 inch.

Grout lift height

Grout is placed in lifts not exceeding 5 feet for low-lift grouting, or as permitted by an approved high-lift procedure. Grout must not free-fall more than 5 feet.

Grout consolidation

Grout is consolidated with a mechanical vibrator or by puddling. The vibrator is inserted into the grout and withdrawn slowly to avoid creating voids in the lift.

Cleanout inspection

Cleanouts at the bottom of grout cells must be inspected before grouting and closed after the cell is verified clean. Grout must not be placed until the hold point is released.

Continuous versus periodic inspection

Continuous special inspection means the inspector is present at all times during the work. Periodic special inspection means visits at intervals specified in the approved inspection plan.

Inspector independence

The special inspector must be qualified and approved by the code official and must be independent of the contractor, reporting findings directly to the owner and code official.