Plan Review: 207 Issues Found

Summary: 219 index entries | 58 perfect matches | 40 mismatched | 121 missing Mismatched (40): A-100: Expected: LOWER TIER PLAN (A-100) | Actual: LOWER TIER PLAN (S-100B)(p7) A-101: Expected: GROUND TIER PLAN (A-101) | Actual: GROUND TIER PLAN (S-101)(p8) A-102: Expected: SECOND TIER PLAN (A-102) | Actual: SECOND TIER PLAN (S-102)(p9) A-103: Expected: THIRD TIER PLAN (A-10...

Why it matters: Addressing this before construction prevents rework and supports code compliance.

Suggested next step: Review drawings and specifications to resolve before construction.

RFI draft: Please clarify: Drawing Index Audit: 121 missing, 40 mismatched out of 219 sheets

Summary: Detail 9 (Divider Beam Detail) specifies L 3 1/2" x 3 1/2" x 3/8" x 9" long angles each side with (4) 3/4" DIA STN STL EXP BOLTS. The Section A-A shows the expansion bolt holes are centered 1 1/2" from the top and bottom edges of the 9" long angles. With 4 bolts distributed in a single line along the remaining 6" (9" minus 1.5" minus 1.5"), the center-to-center spacing between bolts is 6"/3 = 2...

Why it matters: Insufficient anchor spacing can lead to overlapping concrete breakout cones and splitting cracks between anchors, significantly reducing the pullout and shear capacity of the anchor group below design values. This connection supports divider beams at each tier and top tier of the elevator shaft, ...

Suggested next step: Request the structural engineer to verify the expansion anchor spacing in Detail 9 (Divider Beam Detail) and revise the connection to comply with ACI 318-14 Section 17.7.1 minimum spacing of 4da = 3.0" for 3/4" diameter anchors. Potential solutions include: increasing the angl...

RFI draft: Request the structural engineer to verify the expansion anchor spacing in Detail 9 (Divider Beam Detail) and revise the connection to comply with ACI 318-14 Section 17.7.1 minimum spacing of 4da = 3.0" for 3/4" diameter anchors. Potential solution...

Summary: Detail 8 (PRECAST WALL BASE DETAIL) shows a P/C panel or wall resting on a cast-in-place footing or wall with a 2" non-shrink non-stain grout joint. The panel has an 'EMBED PLATE WITH BARS x PANEL HEIGHT' with bars extending upward into the panel, and the footing has an 'EMBEDD PLATE WITH ANCHORS' with anchors embedded downward into the footing. However, no weld plate, reinforcing dowels, ancho...

Why it matters: ACI 318-14 Section 16.3.1.1 requires that factored forces and moments at the base of walls shall be transferred to supporting foundations by bearing on concrete AND by reinforcement, dowels, anchor bolts, or mechanical connectors. Additionally, Section 16.2.1.3 prohibits connection details that r...

Suggested next step: Request that the engineer clarify whether a weld plate or other mechanical connector is required between the embed plates in Detail 8 to transfer lateral and tensile forces across the wall base joint per ACI 318-14 Section 16.3.1.1. If required, request that the detail be revi...

RFI draft: Request that the engineer clarify whether a weld plate or other mechanical connector is required between the embed plates in Detail 8 to transfer lateral and tensile forces across the wall base joint per ACI 318-14 Section 16.3.1.1. If required, r...

Summary: Detail 3 'FOOTING STEP DETAIL' indicates that the bottom reinforcement at the lower footing step transition 'MAY BE CONTINUOUS AT GENERAL CONTRACTOR'S OPTION'. Because upward soil bearing pressure places the bottom of the footing in tension, a continuous bent bar at this concave (re-entrant) corner will tend to straighten under tension. This exerts a downward radial force that will spall the co...

Why it matters: This detailing option violates ACI 318-14 Section 13.2.8.4, which mandates adequate anchorage for tension reinforcement in stepped foundations. Without properly developed, intersecting straight bars at the re-entrant corner, the bar will pull out of the concrete cover, presenting a severe risk of...

Suggested next step: Please revise Detail 3/S-100 to explicitly prohibit a continuous bottom reinforcing bar at the lower footing step transition. Provide a revised detail showing properly developed intersecting straight bars (extending the lower footing bottom bar past the step into the upper foo...

RFI draft: Please revise Detail 3/S-100 to explicitly prohibit a continuous bottom reinforcing bar at the lower footing step transition. Provide a revised detail showing properly developed intersecting straight bars (extending the lower footing bottom bar pa...

Summary: Sheet Note 3 explicitly instructs the precast manufacturer to design the precast walls supporting the PV panel framing for an additional dead load (DL) of 2 KLF and snow load (SL) of 3 KLF. This instruction omits the required wind (W) and earthquake (E) loads that the roof-mounted PV panels will impart to the supporting walls.

Why it matters: ACI 318-14 Section 5.2.1 mandates that loads shall include earthquakes, and Section 5.3.1 requires design for load combinations including wind and earthquake effects. PV panels located on the top tier of an 8-story parking structure will generate significant lateral shear and uplift forces during...

Suggested next step: Please provide the design Wind Load (lateral and uplift) and Earthquake Load reactions from the PV panel framing, and update Sheet Note 3 to require the precast manufacturer to include these loads in the wall design in accordance with Chapter 5.

RFI draft: Please provide the design Wind Load (lateral and uplift) and Earthquake Load reactions from the PV panel framing, and update Sheet Note 3 to require the precast manufacturer to include these loads in the wall design in accordance with Chapter 5.

Summary: The elevations (e.g., Grid 7) show the "GROUND TIER" at EL 207'-4" is an elevated level located 11'-4" above the "LOWER TIER" slab-on-grade (EL 196'-0"). However, both the "SHEAR WALL LATERAL LOADS" schedule and the "LATERAL LOADS" diagram abruptly stop at the "SECOND TIER" and completely omit any seismic lateral loads for the GROUND TIER. Under ACI 318 Sections 5.2.1 and 11.4.1.4, walls must b...

Why it matters: Because the shear wall design is delegated as "Performance Design" to the precast manufacturer, omitting the lateral forces from an elevated tier will result in the precaster underestimating the total base shear and overturning moment. This will lead to dangerously under-designed shear walls, bas...

Suggested next step: Please provide the ultimate seismic lateral loads for the elevated GROUND TIER (and BASEMENT TIER, if applicable) in the Shear Wall Lateral Loads schedule, so the precast manufacturer can design the shear walls and base connections for the complete base shear and overturning m...

RFI draft: Please provide the ultimate seismic lateral loads for the elevated GROUND TIER (and BASEMENT TIER, if applicable) in the Shear Wall Lateral Loads schedule, so the precast manufacturer can design the shear walls and base connections for the complet...

Summary: Detail 16 (IT BEAM CORBEL DETAIL) and Detail 18A (LEDGE DETAIL AT TEE BEARING) depict precast members resting on bearing pads on the cast-in-place ledges without any mechanical connections, weld plates, or reinforcing dowels shown tying the members together. ACI 318-14 Section 16.2.1.3 strictly prohibits connection details that rely solely on friction caused by gravity loads.

Why it matters: If precast elements are installed without positive mechanical connections, they are highly vulnerable to displacement from lateral loads, volume changes, or seismic forces. Relying entirely on friction at the bearing interface could result in a catastrophic loss of bearing and progressive collaps...

Suggested next step: Please update Details 16 and 18A to specify the required mechanical connections, weld plates, or dowels to secure the precast beams to the CIP ledges, ensuring the connection does not rely solely on friction per ACI 318-14 Section 16.2.1.3.

RFI draft: Please update Details 16 and 18A to specify the required mechanical connections, weld plates, or dowels to secure the precast beams to the CIP ledges, ensuring the connection does not rely solely on friction per ACI 318-14 Section 16.2.1.3.

Summary: ASCE 7-16 Section 12.8.3 requires that the lateral seismic force (Fx) induced at any level with mass must be determined and applied as part of the vertical distribution of seismic forces. The "PRECAST LIGHTWALL NOTES" direct the manufacturer to use the "SHEAR WALL LATERAL LOADS" schedule for the "VERTICAL DISTRIBUTION OF SEISMIC FORCES 'F'". However, this schedule only provides lateral loads fr...

Why it matters: The delegated precast manufacturer is instructed to "CONDUCT THEIR OWN LATERAL ANALYSIS FOR MEMBERS AND CONNECTION DESIGN" based on the provided schedule. Without lateral forces specified for the Ground and Lower Tiers, the precast shear walls and their diaphragm shear transfer connections at the...

Suggested next step: Please update the "SHEAR WALL LATERAL LOADS" schedule to include the lateral seismic forces (Fx) for the GROUND TIER and LOWER TIER, ensuring compliance with the vertical distribution requirements of ASCE 7 Section 12.8.3.

RFI draft: Please update the "SHEAR WALL LATERAL LOADS" schedule to include the lateral seismic forces (Fx) for the GROUND TIER and LOWER TIER, ensuring compliance with the vertical distribution requirements of ASCE 7 Section 12.8.3.

Summary: Detail 7 (Precast Connection Detail) specifies a "GALVANIZED A325 NON-THREADED BOLT TACK WELD TO COLUMN HAUNCH PLATE". A325 bolts are high-strength, heat-treated (quenched and tempered) fasteners. Tack welding an A325 bolt destroys its heat treatment, causing severe embrittlement and an unpredictable loss of structural capacity. Because the bolt's strength is critically compromised by the weld,...

Why it matters: Allowing a high-strength bolt to be welded in a primary precast beam-to-column bearing connection creates a highly susceptible point of brittle failure. During an earthquake, the embrittled tack weld or the bolt itself could fracture under lateral or uplift forces, leading to a loss of seating fo...

Suggested next step: Please revise Detail 7 to eliminate welding on A325 high-strength bolts. Consider replacing the A325 bolt with a weldable steel pin (e.g., ASTM A36 or A108) or utilizing a mechanical fastening method that does not subject high-strength structural fasteners to heat input, ensur...

RFI draft: Please revise Detail 7 to eliminate welding on A325 high-strength bolts. Consider replacing the A325 bolt with a weldable steel pin (e.g., ASTM A36 or A108) or utilizing a mechanical fastening method that does not subject high-strength structural ...

Summary: The 'SNOW DRIFT LOADING' detail specifies the applied loads for three adjacent zones: a 'PARKING STALL', a 'DRIVE AISLE', and another 'PARKING STALL'. While the central 'DRIVE AISLE' is correctly labeled with both live and snow loads ('LL +S'), the two 'PARKING STALL' zones are labeled exclusively with snow loads ('MAX DRIFT LOADING (S)' and 'ROOF SNOW LOAD'). ASCE 7-16 Section 4.10.1 requires ...

Why it matters: Parking stalls are the primary structural areas used for the storage of motor vehicles. Excluding vehicular live loads from the design criteria for the parking slabs will result in severely under-designed structural framing in those regions, leading to an immediate risk of structural failure unde...

Suggested next step: Please revise the 'SNOW DRIFT LOADING' detail to include vehicular Live Load (LL) across all structural areas subject to vehicle storage. Update the labels for the 'PARKING STALL' zones to include live load (e.g., 'LL + MAX DRIFT' and 'LL + ROOF SNOW LOAD').

RFI draft: Please revise the 'SNOW DRIFT LOADING' detail to include vehicular Live Load (LL) across all structural areas subject to vehicle storage. Update the labels for the 'PARKING STALL' zones to include live load (e.g., 'LL + MAX DRIFT' and 'LL + ROOF S...

Summary: Sheet note 3 explicitly instructs the contractor to refer to MEP drawings for the location of daps (cutouts) in the precast double tee stems. Precast double tee stems are primary shear and flexural load-bearing elements. Delegating the location of these major structural modifications to MEP drawings without specifying structural boundaries, limits, or requiring explicit structural engineer revi...

Why it matters: If MEP contractors detail daps in high-shear zones (e.g., near supports or point loads) without structural verification, the precast tees could suffer catastrophic shear failure under dead and live loads. This poses a severe safety risk and will likely cause major construction delays or rejected ...

Suggested next step: Submit an RFI to the Structural Engineer requesting allowable zones, maximum dimensions, and reinforcement details for daps in the double tee stems. Confirm that all MEP-located daps must be submitted for structural review and approval prior to precast fabrication.

RFI draft: Submit an RFI to the Structural Engineer requesting allowable zones, maximum dimensions, and reinforcement details for daps in the double tee stems. Confirm that all MEP-located daps must be submitted for structural review and approval prior to pr...

Summary: The "SHEAR WALL LATERAL LOADS" schedule assigns Eighth Tier lateral seismic loads to the shear walls at Grid B-6 (43.98 kips) and Grid B-7 (35.25 kips). However, the detailed elevations for Grid 6 and Grid 7 show the shear walls at Grid B terminating at "T.O. WALL 282'-2"", which is 4.5 feet below the Eighth Tier floor elevation of 286'-8". A shear wall that physically does not extend to a floo...

Why it matters: This indicates a critical discrepancy between the structural analytical model and the detailed drawings. The analytical model likely assumed these walls extended to the Eighth Tier, meaning their stiffness drew seismic forces that they physically cannot receive as detailed. This completely breaks...

Suggested next step: Clarify if the shear walls at Grid B-6 and B-7 should extend up to the Eighth Tier (EL 286'-8"). If the elevation details are correct (walls terminate at 282'-2"), please revise the seismic analytical model to remove these walls from the Eighth Tier, redistribute the lateral l...

RFI draft: Clarify if the shear walls at Grid B-6 and B-7 should extend up to the Eighth Tier (EL 286'-8"). If the elevation details are correct (walls terminate at 282'-2"), please revise the seismic analytical model to remove these walls from the Eighth Ti...

Summary: Detail 15 ('HSS BEAM/BEAM DETAIL') depicts a horizontal HSS beam framing perpendicularly into another HSS member, but the detail only calls out to 'CAP END OF HSS BEAM WITH 1/4" CAP PLATE'. The drawing completely omits any required structural connection mechanism (such as welds, connection angles, or bolts) between the two beams.

Why it matters: ASCE 7-16 Sections 12.1.3 and 12.1.4 require that a continuous load path be established to transfer forces, and that a positive connection must be provided for every beam or girder to directly attach it to its supporting elements. The omission of a connection in this detail leaves the beam withou...

Suggested next step: Please revise the HSS BEAM/BEAM DETAIL to specify the required positive structural connection (e.g., specific weld symbols, shear tabs, or connection angles) between the HSS beams to ensure a continuous load path in accordance with ASCE 7 Sections 12.1.3 and 12.1.4.

RFI draft: Please revise the HSS BEAM/BEAM DETAIL to specify the required positive structural connection (e.g., specific weld symbols, shear tabs, or connection angles) between the HSS beams to ensure a continuous load path in accordance with ASCE 7 Sections...

Summary: Detail 5 'HSS TO P/C WALL CONNECTION' specifies an 8-inch thick wall panel with an embed plate using (6) #6 anchors. The callout indicates an anchor length of either 8 inches or 1'-6" (18 inches). In either case, the anchor length equals or exceeds the 8-inch wall thickness, meaning the anchors will either protrude entirely through the wall or have zero concrete cover on the far side.

Why it matters: Without sufficient concrete cover behind the anchor, a proper concrete breakout cone cannot form, preventing the anchor from developing its required tension capacity. This violates the building code requirement that connections must extend into the concrete a sufficient distance to fully develop ...

Suggested next step: Revise Detail 5 to either increase the precast wall panel thickness or reduce the anchor embedment length to provide the required concrete cover for full tension development.

RFI draft: Revise Detail 5 to either increase the precast wall panel thickness or reduce the anchor embedment length to provide the required concrete cover for full tension development.

Summary: Detail 13 shows a 'PRECAST TEE' bearing on a 'CIP WALL' using a 'MASTICORD BEARING PAD WITH TEFLON ON TOP GLUED TO ANGLE'. A '1"' gap filled with 'CONTINUOUS BACKER ROD AND SEALANT' completely separates the tee from the wall face. No mechanical or positive connection is provided between the Precast Tee and its supporting element (the CIP wall) or to a diaphragm connected to the support. The Tef...

Why it matters: Without a positive connection, the Precast Tee could slide off its bearing angle during a seismic event, leading to a local collapse. The 1" gap and Teflon pad sever the continuous load path required by Section 12.1.3, preventing proper transfer of seismic forces between the diaphragm and the sup...

Suggested next step: Please revise Detail 13 to include a positive mechanical connection (such as a slotted bolted connection or shear plate) between the Precast Tee and the CIP Wall that meets the 5% minimum horizontal connection requirement of ASCE 7 Section 12.1.4.

RFI draft: Please revise Detail 13 to include a positive mechanical connection (such as a slotted bolted connection or shear plate) between the Precast Tee and the CIP Wall that meets the 5% minimum horizontal connection requirement of ASCE 7 Section 12.1.4.