Evaluator: XXX Evaluator: EGM/BL Date: 05/10/2019...Building Name: California Hall Evaluator: EGM/BL...

Evaluator: XXX Evaluator: EGM/BL

Date: 05/10/2019

Page 1

07-15-19

ASCE 41-17 Tier 1 Seismic Evaluation

Building Name: California Hall

CAAN ID: 1270

Auxiliary Building ID: Not applicable

Address: Core Campus, Berkeley, 94720

Site location coordinates: Latitude 37.871667 o Longitudinal -122.260278 o

Plan West Elevation

UCOP SEISMIC PERFORMANCE LEVEL (OR “RATING”) BASED ON TIER 1 EVALUATION FINDINGS: V

BUILDING DATA

ASCE 41-17 Model Building Type (Governing Building Type bolded for Seismic Risk Model when multiple

types exist):

a. Longitudinal Direction: URMa: Unreinforced Masonry Bearing Walls (with Stiff Diaphragm) and

C2: Concrete Shear Walls (with Stiff Diaphragms)

b. Transverse Direction: URMa: Unreinforced Masonry Bearing Walls (with Stiff Diaphragm) and C2:

Concrete Shear Walls (with Stiff Diaphragms)

Square Footage: 56,454 sq. ft. (UCB Records)

Building Length: 200’-0” in N-S direction

Building Width: 70’-0” in E-W direction

Building Height: 68’-10” to top high point of roof

Story Height: 11’-6” (basement – First floor), 18’-6” (First floor – Second floor), 14’-10” (Second floor –

Attic), 24’-0” (Attic – roof at high point). Grade is located at the First floor.

Number of stories above grade: 3

Number of basement stories below grade: 1

Year of Original Construction and Code Year: Construction was completed in 1905. The drawings are dated

1904 (prior to the Building Code)

Year of Later Constuction and Code Year: 1968 (1967 UBC assumed) and retrofit 1991 (1988 UBC assumed)

COST RANGE TO RETROFIT (if applicable): High: $200-$400 per square foot

Building Name: California Hall Evaluator: EGM/BL

CAAN ID: 1270 Date: 05/10/2019

Page 2

BUILDING DESCRIPTION

General

California Hall is located on the core UC Berkeley campus to the west of the Doe Library and to the south

of the Moffitt Library. It is an unreinforced masonry building with one story below grade and three stories

above grade and measures 70’-0” in the east-west direction by 200’-0” in the north-south direction. It is

one of the oldest structures on the Berkeley campus having been constructed in 1905. California Hall

contains exterior load-bearing masonry walls and a hipped roof slab that supports clay tiles. A large

skylight runs down the length of the building in the N-S direction. At the time of construction, the skylight

delivered natural light deep into the interior space of each story through a series of rectangular slab

openings located at each floor level. It also contained a large lecture hall at the First Floor with a sloped

structural floor slab.

Several interior renovations have been completed to date including two major structural modifications in

1968 and 1991. California Hall is currently occupied by administrative offices and used for storage of office

furniture.

Structural System

The 1905 gravity load-carrying system is comprised of a 4” and 5” thick one-way reinforced concrete slab

that spans to steel “I” beams and girders. The beams range in depth from 9” to 12” and are typically

spaced 5’-6” apart. Their span ranges from 15’-6” to 23’-6”. The girders are 18”, 21”, and 24” deep and

span up to 28’-0”. They are supported by a row of steel columns on the building interior and by load-

bearing masonry walls at the building perimeter. The steel beams, girders, and columns are encased with

concrete fireproofing. The roof consists of a 3” thick concrete slab that spans to sloped steel beams and

girders.

In 1968, the lecture hall located at the first floor was demolished. The slab opening that remained was

infilled with a 3” thick one-way concrete slab that spans to reinforced concrete joists and girders. The

joists have an average width of 5” and are 10” deep. They are spaced at 2’-0” o.c and span up to 20’-3”.

The girders span 28’-0” and are 16” wide and 2’-3” deep. They are supported by two reinforced concrete

columns at the building interior and by masonry walls reinforced with shotcrete at the building perimeter.

In 1968, the skylight openings at each floor were infilled with concrete fill over metal deck that spans to a

combination of new and existing steel framing.

The 1905 lateral load-resisting system consists of unreinforced masonry walls in both directions. In the

longitudinal direction, the lateral system is comprised of exterior walls located on the east and west

elevation. In the transverse direction, the lateral system is comprised from four walls. These walls are

located on the north and south exterior elevation, and two interior walls are located adjacent to the main

entrance of the building.

In 1991, shotcrete was added to the inside face of the masonry walls. The shotcrete is 6” thick in the

basement story, on the north elevation, and on the south elevation. It is 4 ½” thick on all other walls. The

shotcrete walls are reinforced with a single layer of #4 bar spaced at 12” each way. Vertical and horizontal

ribs measuring 4 ½” deep x 9” wide were chipped into the existing masonry walls prior to the application

of the shotcrete. These ribs, along with epoxy dowels, bond the shotcrete to the masonry. The shotcrete

is anchored to the brick with ¾” diameter epoxy threaded rods spaced at 4’-0” in the horizontal direction

and 3’-0” o.c. in the vertical direction. The shotcrete walls are doweled into the existing foundation walls


CAAN ID: 1270 Date: 05/10/2019

Page 3

at the top of the basement slab. They do not contain their own foundation system. Connection plates

spaced at 4’-0” o.c. and 5’-0” o.c. were added to directly connect the reinforced concrete slab to the

masonry walls. The plates are bolted to the underside of the slab and contain a welded threaded rod that

is epoxy doweled into the wall. The girders are also directly connected to the masonry walls. Their bottom

flange is welded to a steel angle that is epoxy doweled to the masonry wall with a threaded rod.

The 1905 foundation consists of unreinforced concrete piers located below brick wall piers. These piers

were specified to extend down to “good” soil which varies in depth from 3’-0” to 22’-0” below the

basement floor level. The elevation of “good” soil is identified on the original construction drawings. The

interior masonry walls are supported by continuous unreinforced concrete wall footings and the interior

columns are supported by spread footings. No modifications to the foundation were made as part of the

1968 renovation or the 1991 seismic correction.

The building is clad with 8” thick stone panels. In the 1991 seismic correction, epoxy anchors were added

to connect the shotcrete to the masonry walls. However, these anchors do not appear to extend into the

stone cladding. At this time, the connection of the stone to the masonry is unknown.

Building Condition: Good. However, some settlement was observed near the south end of the structure.

Date of Site Visit: 03/26/2019, Bret Lizundia and Emma Meehan, Rutherford + Chekene

Limitations of walk-through: Not all rooms were entered.

SITE INFORMATION

Site Class (A-F): C Basis: Site Specific Zone Map of campus by GeoMatrix

Site Specific Ground Motion Study? Yes, 2015 Update to the Site-Specific Seismic Hazard Analyses and

Development of Seismic Design Ground Motions

BSE-1N Spectral Accelerations: Basis: 2015 Update to the Site-Specific Seismic Hazard Analyses and

Development of Seismic Design Ground Motions, Table 5 for 10 ft – 35 ft Soil based on depth of rock

readings from Site Specific Zone Map of campus by Geomatrix

SDS: 2.34g SD1: 0.72g

BSE-2E Spectral Accelerations: Basis: 2015 Update to the Site-Specific Seismic Hazard Analyses and

Development of Seismic Design Ground Motions, Table 6 for 10 ft - 35 ft Soil based on depth of rock

readings from Site Specific Zone Map of campus by Geomatrix

SXS: 3.16g SX1: 0.96g

Level of Seismicity: High

Performance Level: Collapse Prevention Structural Performance

Geologic Hazards:

Fault Rupture: No Basis: CGS website http://maps.conservation.ca.gov/cgs/informationwarehouse/

Liquefaction: No Basis: CGS website http://maps.conservation.ca.gov/cgs/informationwarehouse/

Landslide: No Basis: CGS website http://maps.conservation.ca.gov/cgs/informationwarehouse/

PREVIOUS RATINGS SUMMARY

Good - 1997 Preliminary Seismic Evaluation (SAFER), Forell/Elsesser Engineers, Inc.


CAAN ID: 1270 Date: 05/10/2019

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DOCUMENTATION

Architectural Drawings:

California Hall, University of California, Berkeley, California, John Galen Howard Architect,

September 1903, Sheets 1 to 13.

California Hall Alteration, University of California Berkeley, Germano Milono & Associates, January

1968, Sheets 1 to 24.

California Hall, Seismic Safety Corrections, University of California Berkeley, Hansen / Murakami /

Eshima, Inc. April 10, 1990, A-1 to A-13.

Structural Drawings:

California Hall, University of California, Berkeley, California, John Galen Howard Architect, January

13, 1904, Sheets 100 to 105 and 300 to 304.

California Hall Alteration, University of California Berkeley, Germano Milono, January 25, 1968,

Sheets S-1 to S-7

California Hall, Seismic Safety Corrections, University of California Berkeley, David Logan

Messinger & Associates Inc., April 10, 1990, S-1 to S-9.

Seismic Evaluations: 1997 Preliminary Seismic Evaluation (SAFER), Forell/Elsesser Engineers, Inc.

Geotechnical Reports: None

Other Documents: Master Planning Report for California Hall, University of California, Berkeley,

Cody Anderson Wasney Architects, January, 22 2009.

CONSTRUCTION DATA

Gravity Load Structural System: Concrete slab that spans to steel beams and joists supported by

steel columns and masonry bearing walls. Beams, joists and

columns are covered with concrete for fireproofing.

Exterior Transverse Walls: Unreinforced masonry bearing

walls with shotcrete on

interior face

Opening(s)? Openings occur

for doors,

windows, and

MEP services

Exterior Longitudinal Walls: Unreinforced masonry bearing

walls with shotcrete on

interior face

Opening(s)? Openings occur

for doors,

windows, and

MEP services

Roof Materials/Framing: 4” thick slab spanning to steel beams and columns covered with

concrete for fireproofing.

Intermediate Floors/Framing: 4” and 5” thick slab spanning to steel beams and columns covered

with concrete for fireproofing. At Level 1 1968 infill, a 3” thick slab

spans to concrete framing.

Ground Floor: 6” thick concrete slab-on-grade with 2” of additional concrete

poured in 1968


CAAN ID: 1270 Date: 05/10/2019

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Columns: Built-up steel columns covered

with concrete for fireproofing,

and (2) 16” square reinforced

concrete columns added in

1968

Foundation: Square

unreinforced

concrete piers

below columns

and continuous

wall footing

below

foundation wall

General Condition of Structure: Good

Evidence of Settling?: Basement slab in southeast corner of the building is cracking

approximately 20 ft from the exterior wall. Cracks in the surface

paving on the building exterior were observed in the same location.

The exterior wall is undamaged.

Special Features & Comments:

LATERAL-FORCE-RESISTING SYSTEM

Longitudinal Transverse

ASCE 41-17 Building Type: URMa: unreinf. masonry

bearing walls (w/ stiff

diaphragms)

URMa: unreinf. masonry

bearing walls (w/ stiff

diaphragms)

Diaphragms: 3”, 4”, and 5”conc. slab 3”, 4”, and 5” conc. slab

Vertical Elements: Steel columns encased with

concrete fireproofing, and

URM walls with shotcrete on

one side

Steel columns encased with

concrete fireproofing, and

URM walls with shotcrete on

one side

Connections: Steel beams bear on URM

walls. In 1991 corrections,

epoxy dowels into URM

walls. No reinforcement

between concrete

foundation and URM wall

transition.

Steel beams bear on URM

walls. In 1991 corrections,

epoxy dowels into URM

walls. No reinforcement

between concrete

foundation and URM wall

transition.

Details: Sheets 100 to 103 (1904),

Sheets S-2 to S-7 (1991) for

connections

Sheets 100 to 103 (1904),

Sheets S-2 to S-7 (1991) for

connections

Estimated Fundamental Period, T (sec): 0.42 sec 0.42 sec

BSE-2E Spectral Acceleration, Sa: 2.274 g 2.274 g

Modification Factor, C: 1.0 (URMa and C2:

Table 4-7 in ASCE 41-17)

1.0 (URMa and C2:

Table 4-7 in ASCE 41-17)

Building Weight, W (kips): 17,070 kips 17,070 kips

Seismic Base Shear, V (kips): 38,820 kips 38,820 kips

System Modification Factor, Ms: 1.75 for URM walls,

4.5 for shotcrete and

concrete foundation walls

1.75 for URM walls,

4.5 for shotcrete and

concrete foundation walls


CAAN ID: 1270 Date: 05/10/2019

Page 6

Significant Structural Deficiencies, Potentially Affecting Seismic Performance Level Designation:

� Lateral System Stress Check (wall shear, column shear or flexure, or brace axial as applicable)

☐ Load Path

☐ Adjacent Buildings

☐ Weak Story

☐ Soft Story

☐ Geometry (vertical irregularities)

☐ Torsion

☐ Mass – Vertical Irregularity

☐ Cripple Walls

☐ Wood Sills (bolting)

☐ Diaphragm Continuity

☐ Openings at Shear Walls (concrete or masonry)

☐ Liquefaction

☐ Slope Failure

☐ Surface Fault Rupture

☐ Masonry or Concrete Wall Anchorage at Flexible Diaphragm

☐ URM wall height to thickness ratio

☐ URM Parapets or Cornices

☐ URM Chimney

☐ Heavy Partitions Braced by Ceilings

☐ Appendages

OVERALL SEISMIC DEFICIENCIES & EXPECTED SEISMIC PERFORMANCE

California Hall is a rectangular structure that contains symmetrically located masonry walls. It does not

contain significant irregularities. However, it does appear to lack adequate lateral shear capacity.

In the Tier 1 evaluation, the story shear was proportioned between the masonry and shotcrete walls by

relative rigidity. The stress in the masonry is 56 psi, 93 psi, and 91 psi from the Attic-Second Floor, Second

Floor-First Floor, and First Floor-Basement, respectively. This exceeds the Tier 1 stress limit of 30 psi for

clay masonry. The stress in the shotcrete is 221 psi, 368 psi, and 362 psi from the Attic-Second Floor,

Second Floor-First Floor, and First Floor-Basement, respectively. This exceeds the Tier 1 stress limit of 141

psi for concrete with a compressive strength of 5,000 psi.

A subsequent shear check was completed to compare the demands prescribed by new building design to

the wall capacities allowed by the concrete in combination with the reinforcing. The calculations were

performed in accordance with ASCE 7-10, and only the shotcrete walls were used in the calculation. This

check also indicated that the walls are overstressed.

The anchorage of the stone cladding to the masonry is unknown. These panels occur over main egress

paths, and it is recommended that the connectivity of the panels be verified in the field.


CAAN ID: 1270 Date: 05/10/2019

Page 7

Finally, a series of large central skylight openings were infilled at each floor level during renovations made

to California Hall. This infill serves as a crucial part of the diaphragm capacity and lateral load path. It is

beyond the scope of the Tier 1 checklist to confirm the adequacy of the infills. It is recommended that

further analysis be completed to understand if the infill slabs form reliable continuity of the floor

diaphragm.

Seismic Performance Level Rating

A Seismic Performance Level rating of Level V is assigned to California Hall based on the Tier 1 evaluation,

including review of the details and analytical results, because of the deficiencies identified above,

including highly stressed walls and the falling hazard posed by potentially unanchored stone veneer.

Recommended Next Step

It is recommended that an ASCE 41 Tier 3 nonlinear analysis be completed for this structure to determine

the adequacy of the shear walls and the diaphragm to resist the expected displacements. Since this

structure has not passed an ASCE 7-10 check, which is a linear force-based approach, it is unlikely that it

would benefit from a Tier 2 or linear Tier 3 procedure. A deformation-based approach afforded by Tier 3

analysis can be beneficial to a stiff shear wall structure such as California Hall. In addition, the 3D analytical

model can determine the force distribution between the masonry and the shotcrete. Finally, a field

investigation can be completed to verify the anchorage of the stone cladding to the masonry.

Seismic Retrofit Concept Sketches/Description (only if above-listed rating is V or greater):

• Shear capacity can be added by strengthening the existing walls with shotcrete or composite fiber.

• Remove existing diaphragm infills and replace them with a reinforced concrete slab that is

comprehensively connected to the original slab. Add collectors to interior shear walls.

• If no anchors are found in the field investigation, install stainless steel adhesive drilled dowels

from the interior of the building. The dowels will penetrate the shotcrete, masonry, and embed

into the stone veneer.

Appendices

A. Additional Images

B. ASCE 41-17 Tier 1 Checklists (Structural)

C. UCOP Seismic Safety Policy Falling Hazards Assessment Summary

D. Quick Check Calculations

APPENDIX A

Additional Images

Building Name: California Hall Evaluator: EMG/BL

CAAN ID: 1270 Date: 04/03/19 Date: 05/10/2019

Page 2

Plan

Second floor structural plan


CAAN ID: 1270 Date: 04/03/19 Date: 05/10/2019

Page 3

South elevation (looking northwest)

East elevation (looking northwest)


CAAN ID: 1270 Date: 04/03/19 Date: 05/10/2019

Page 4

West elevation (looking east)

North elevation (looking south)


CAAN ID: 1270 Date: 04/03/19 Date: 05/10/2019

Page 5

Attic floor below skylight (looking north)

Cracking in exterior paving at south elevation and outboard of area in

basement with settlement issues


CAAN ID: 1270 Date: 04/03/19 Date: 05/10/2019

Page 6

Interior corridor

Light fixture over main lobby entrance

APPENDIX B

ASCE 41-17 Tier 1 Checklists (Structural)

UC Campus: Berkeley Date: 05/10/2019

Building CAAN: 1270 Auxiliary CAAN:

By Firm: RUTHERFORD + CHEKENE

Building Name: California Hall Initials: EGM Checked: BL

Building Address: Core Campus, Berkeley, 94720 Page: 1 of 3

ASCE 41-17

Collapse Prevention Basic Configuration Checklist

Note: C = Compliant NC = Noncompliant N/A = Not Applicable U = Unknown

LOW SEISMICITY

BUILDING SYSTEMS - GENERAL

Description

C NC N/A U

LOAD PATH: The structure contains a complete, well-defined load path, including structural elements and connections, that

serves to transfer the inertial forces associated with the mass of all elements of the building to the foundation. (Commentary:

Sec. A.2.1.1. Tier 2: Sec. 5.4.1.1)

Comments: Transition between URM walls and foundation concrete walls relies on friction and shear key. Diaphragm connectivity to URM walls was improved in 1990 retrofit with the inclusion of epoxy dowels to

transfer load from diaphragm to walls.

C NC N/A U

Op

Op

Op

ADJACENT BUILDINGS: The clear distance between the building being evaluated and any adjacent building is greater than

0.25% of the height of the shorter building in low seismicity, 0.5% in moderate seismicity, and 1.5% in high seismicity.

(Commentary: Sec. A.2.1.2. Tier 2: Sec. 5.4.1.2)

Comments: There are no adjacent structures.

C NC N/A U

MEZZANINES: Interior mezzanine levels are braced independently from the main structure or are anchored to the seismic-

force-resisting elements of the main structure. (Commentary: Sec. A.2.1.3. Tier 2: Sec. 5.4.1.3)

Comments: There are no mezzanines.

BUILDING SYSTEMS - BUILDING CONFIGURATION

Description

C NC N/A U

WEAK STORY: The sum of the shear strengths of the seismic-force-resisting system in any story in each direction is not

less than 80% of the strength in the adjacent story above. (Commentary: Sec. A2.2.2. Tier 2: Sec. 5.4.2.1)

Comments: Walls are continuous to the foundation.

C NC N/A U

SOFT STORY: The stiffness of the seismic-force-resisting system in any story is not less than 70% of the seismic-force-

resisting system stiffness in an adjacent story above or less than 80% of the average seismic-force-resisting system stiffness

of the three stories above. (Commentary: Sec. A.2.2.3. Tier 2: Sec. 5.4.2.2)

Comments: Walls are continuous to the foundation and are assumed to be controlled by shear

deformation which is linearly related to story height. Level 1- Level 2 is 18’-6” and Level 2-Attic is 14’-10”. The ratio of the story height is 80% which is larger than the 70% trigger.






ASCE 41-17



C NC N/A U

VERTICAL IRREGULARITIES: All vertical elements in the seismic-force-resisting system are continuous to the foundation.

(Commentary: Sec. A.2.2.4. Tier 2: Sec. 5.4.2.3)

Comments: Shotcrete added in 1990 terminates at the top of the basement slab.

C NC N/A U

GEOMETRY: There are no changes in the net horizontal dimension of the seismic-force-resisting system of more than 30%

in a story relative to adjacent stories, excluding one-story penthouses and mezzanines. (Commentary: Sec. A.2.2.5. Tier 2:

Sec. 5.4.2.4)

Comments:

C NC N/A U

MASS: There is no change in effective mass of more than 50% from one story to the next. Light roofs, penthouses, and

mezzanines need not be considered. (Commentary: Sec. A.2.2.6. Tier 2: Sec. 5.4.2.5)

Comments:

C NC N/A U

TORSION: The estimated distance between the story center of mass and the story center of rigidity is less than 20% of

the building width in either plan dimension. (Commentary: Sec. A.2.2.7. Tier 2: Sec. 5.4.2.6)

Comments: Walls are symmetrically located.

MODERATE SEISMICITY (COMPLETE THE FOLLOWING ITEMS IN ADDITION TO THE ITEMS FOR LOW SEISMICITY)

GEOLOGIC SITE HAZARD

Description

C NC N/A U

LIQUEFACTION: Liquefaction-susceptible, saturated, loose granular soils that could jeopardize the building’s seismic

performance do not exist in the foundation soils at depths within 50 ft (15.2m) under the building. (Commentary: Sec. A.6.1.1.

Tier 2: 5.4.3.1)

Comments: Per the CGS website http://maps.conservation.ca.gov/cgs/informationwarehouse/

C NC N/A U

SLOPE FAILURE: The building site is located away from potential earthquake-induced slope failures or rockfalls so that it is unaffected by such failures or is capable of accommodating any predicted movements without failure. (Commentary: Sec. A.6.1.2. Tier 2: 5.4.3.1)


C NC N/A U

SURFACE FAULT RUPTURE: Surface fault rupture and surface displacement at the building site are not anticipated.

(Commentary: Sec. A.6.1.3. Tier 2: 5.4.3.1)







ASCE 41-17



HIGH SEISMICITY (COMPLETE THE FOLLOWING ITEMS IN ADDITION TO THE ITEMS FOR MODERATE SEISMICITY)

FOUNDATION CONFIGURATION

Description

C NC N/A U

OVERTURNING: The ratio of the least horizontal dimension of the seismic-force-resisting system at the foundation level to the building height (base/height) is greater than 0.6Sa. (Commentary: Sec. A.6.2.1. Tier 2: Sec. 5.4.3.3)

Comments: On Grid 5, B=70 ft, H=58.33 ft (average roof height), B/H = 1.2 Sa = 2.274g for UCB at BSE 2

0.6x Sa = 1.364 B/H < 0.6 Sa

C NC N/A U

TIES BETWEEN FOUNDATION ELEMENTS: The foundation has ties adequate to resist seismic forces where footings, piles, and piers are not restrained by beams, slabs, or soils classified as Site Class A, B, or C. (Commentary: Sec. A.6.2.2. Tier 2: Sec. 5.4.3.4)

Comments: Soil Site Class C.






ASCE 41-17

Collapse Prevention Structural Checklist For Building Type C2-C2A


Low And Moderate Seismicity

Seismic-Force-Resisting System

Description

C NC N/A U

COMPLETE FRAMES: Steel or concrete frames classified as secondary components form a complete vertical-load-carrying system. (Commentary: Sec. A.3.1.6.1. Tier 2: Sec. 5.5.2.5.1) Comments: Shotcrete is applied to existing masonry walls. Masonry walls are load bearing.

C NC N/A U

REDUNDANCY: The number of lines of shear walls in each principal direction is greater than or equal to 2. (Commentary: Sec. A.3.2.1.1. Tier 2: Sec. 5.5.1.1)

Comments: 2 lines of walls occur in the longitudinal direction, and 4 lines of walls occur in the transverse direction.

C NC N/A U

SHEAR STRESS CHECK: The shear stress in the concrete shear walls, calculated using the Quick Check procedure of Section 4.4.3.3, is less than the greater of 100 lb/in.2 (0.69 MPa) or 2√f’c. (Commentary: Sec. A.3.2.2.1. Tier 2: Sec. 5.5.3.1.1)

Comments: The story shear is proportioned between the masonry and the shotcrete based upon relative rigidity. The calculated stresses in the shotcrete walls are 362 psi, 368 psi, and 221 psi between Basement-First Floor, First Floor-Second Floor, and Second Floor to Attic respectively. These stresses exceed the limit of 141 psi for 5000 psi concrete. The shotcrete walls were subsequently checked using ASCE 7-10 for the total story shear and are inadequate.

C NC N/A U

REINFORCING STEEL: The ratio of reinforcing steel area to gross concrete area is not less than 0.0012 in the vertical direction and 0.0020 in the horizontal direction. (Commentary: Sec. A.3.2.2.2. Tier 2: Sec. 5.5.3.1.3)

Comments: At a minimum, ρ = 0.0027 (#4 @ 12” o.c. E.W., E.F. in a 6” wall)

Connections

Description

C NC N/A U

WALL ANCHORAGE AT FLEXIBLE DIAPHRAGMS: Exterior concrete or masonry walls that are dependent on flexible diaphragms for lateral support are anchored for out-of-plane forces at each diaphragm level with steel anchors, reinforcing dowels, or straps that are developed into the diaphragm. Connections have strength to resist the connection force calculated in the Quick Check procedure of Section 4.4.3.7. (Commentary: Sec. A.5.1.1. Tier 2: Sec. 5.7.1.1)

Comments: Building has rigid diaphragms.






ASCE 41-17



C NC N/A U

TRANSFER TO SHEAR WALLS: Diaphragms are connected for transfer of seismic forces to the shear walls. (Commentary: Sec. A.5.2.1. Tier 2: Sec. 5.7.2)

Comments:

C NC N/A U

FOUNDATION DOWELS: Wall reinforcement is doweled into the foundation with vertical bars equal in size and spacing to the vertical wall reinforcing directly above the foundation. (Commentary: Sec. A.5.3.5. Tier 2: Sec. 5.7.3.4)

Comments: Epoxy dowels into the foundation walls were added to match vertical wall reinforcing in the 1990 seismic retrofit.

High Seismicity (Complete The Following Items In Addition To The Items For Low And Moderate Seismicity)

Seismic-Force-Resisting System

Description

C NC N/A U

DEFLECTION COMPATIBILITY: Secondary components have the shear capacity to develop the flexural strength of the components. (Commentary: Sec. A.3.1.6.2. Tier 2: Sec. 5.5.2.5.2)

Comments: Steel columns occur in the building.

C NC N/A U

FLAT SLABS: Flat slabs or plates not part of the seismic-force-resisting system have continuous bottom steel through the column joints. (Commentary: Sec. A.3.1.6.3. Tier 2: Sec. 5.5.2.5.3)

Comments: There are no flat slabs.

C NC N/A U

COUPLING BEAMS: The ends of both walls to which the coupling beam is attached are supported at each end to resist vertical loads caused by overturning. (Commentary: Sec. A.3.2.2.3. Tier 2: Sec. 5.5.3.2.1)

Comments: There are no coupling beams.

Diaphragms (Stiff Or Flexible)

Description

C NC N/A U

DIAPHRAGM CONTINUITY: The diaphragms are not composed of split-level floors and do not have expansion joints. (Commentary: Sec. A.4.1.1. Tier 2: Sec. 5.6.1.1)

Comments:






ASCE 41-17



C NC N/A U

OPENINGS AT SHEAR WALLS: Diaphragm openings immediately adjacent to the shear walls are less than 25% of the wall length. (Commentary: Sec. A.4.1.4. Tier 2: Sec. 5.6.1.3)

Comments: Central stairs and elevator openings are immediately adjacent to interior walls and span approximately the entire length of the wall.

Flexible Diaphragms

Description

C NC N/A U

CROSS TIES: There are continuous cross ties between diaphragm chords. (Commentary: Sec. A.4.1.2. Tier 2: Sec. 5.6.1.2)


C NC N/A U

STRAIGHT SHEATHING: All straight-sheathed diaphragms have aspect ratios less than 2-to-1 in the direction being considered. (Commentary: Sec. A.4.2.1. Tier 2: Sec. 5.6.2)


C NC N/A U

SPANS: All wood diaphragms with spans greater than 24 ft (7.3 m) consist of wood structural panels or diagonal sheathing. (Commentary: Sec. A.4.2.2. Tier 2: Sec. 5.6.2)


C NC N/A U

DIAGONALLY SHEATHED AND UNBLOCKED DIAPHRAGMS: All diagonally sheathed or unblocked wood structural panel diaphragms have horizontal spans less than 40 ft (12.2 m) and aspect ratios less than or equal to 4-to-1. (Commentary: Sec. A.4.2.3. Tier 2: Sec. 5.6.2)


C NC N/A U

OTHER DIAPHRAGMS: Diaphragms do not consist of a system other than wood, metal deck, concrete, or horizontal bracing. (Commentary: Sec. A.4.7.1. Tier 2: Sec. 5.6.5)


Connections

Description

C NC N/A U

UPLIFT AT PILE CAPS: Pile caps have top reinforcement, and piles are anchored to the pile caps. (Commentary: Sec. A.5.3.8. Tier 2: Sec. 5.7.3.5)

Comments: There are no pile caps.

APPENDIX C

UCOP Seismic Safety Policy Falling Hazards Assessment

Summary



By Firm: Rutherford+Chekene


Building Address: Core Campus, Berkeley 94720 Page: 1 of 1

UCOP SEISMIC SAFETY POLICY

Falling Hazard Assessment Summary

Note: P= Present, N/A = Not Applicable

Description

P N/A

Heavy ceilings, features or ornamentation above large lecture halls, auditoriums, lobbies, or other areas where large numbers of people congregate (50 ppl or more)

Comments:

P N/A

Heavy masonry or stone veneer above exit ways or public access areas

Comments: Anchorage of stone cladding to exterior masonry walls is unknown.

P N/A

Unbraced masonry parapets, cornices, or other ornamentation above exit ways or public access areas

Comments:

P N/A

Unrestrained hazardous material storage

Comments:

P N/A

Masonry chimneys

Comments:

P N/A

Unrestrained natural gas-fueled equipment such as water heaters, boilers, emergency generators, etc.

Comments:

P N/A

Other:

Comments:

P N/A

Other:

Comments:

P N/A

Other:

Comments:

Falling Hazards Risk: Low

APPENDIX D

Quick Check Calculations

RUTHERFORD + CHEKENE TIER 1 EVALUATION

Flat Load Tables

Seismic Weight Dead Load

ROOF

Skylight psf psf Remarks

Copper framing around glass 28 28 3/4" thick copper band assumed

1/2" wire glass 7 7

Girders / Joists 8 8 Steel trusses below skylight

Lighting, MEP, misc. 2 2

Total 44 44

1- No ceiling or partitions occur. MEP consists of sprinklers, a singe duct, and electrical


ROOF

Typical Roof psf psf Remarks

Clay tile roof 15 15

Waterproofing 2 2

Slab 50 50 4" slab above steel beams

Girders / Joists 55 55 Steel framing encased in concrete fireproofing

Lighting, MEP, misc. 3 3

Total 125 125

1- No ceiling or partitions occur. MEP consists of sprinklers, few ducts, and electrical


ATTIC

1968 Central Floor Infill psf psf Remarks

Slab 33 33 2" LWC fill over 2" deck

Beams/girders 50 50 Steel framing encased in concrete fireproofing

MEP 5 5 Mechanical, electrical and plumbing

Ceiling, lighting and misc. 4 4

Columns 6 0 Steel columns with concrete fireproofing

Partitions 5 0

Total 103 92

1- No floor finish at attic.


ATTIC

Original Floor psf psf Remarks

Slab 50 50 4" NWC slab




Columns 6 0 Steel columns with concrete fireproofing

Partitions 5 5 Partitions below

Total 128 122

1- No floor finish occurs



2ND FLOOR

Typical Floor psf psf Remarks

Flooring 5 5 Floor tiles





Columns 9 Steel columns with concrete fireproofing

Partitions 10 10

Total 144 135


1ST FLOOR

Original Floor psf psf Remarks







Partitions 10 10

Total 137 129


1ST FLOOR

1968 North Floor Infill psf psf Remarks


Slab 38 38 3" NWC slab.

Beams/girders 45 45 RC beams and joists below 3" thick NWC slab




Partitions 10 10

Total 114 106


Story Weight120 pcf 150 pcf 170 pcf wglass = 15 psf

Floor Levels

ROOF

Skylight

ROOF

Typical Roof

ATTIC

1968 Central

Floor Infill

ATTIC

Original Floor

2ND FLOOR

Typical Floor

1ST FLOOR

Original Floor

1ST FLOOR

1968 North

Floor Infill

ROOF

Skylight

ROOF

Typical Roof

ATTIC

1968 Central

Floor Infill

ATTIC

Original

Floor

2ND FLOOR

Typical Floor

1ST FLOOR

Original

Floor

1ST FLOOR

1968 North

Floor Infill

Wall height

below floor

level (ft)

Wall height

tributary to each

floor level

(ft)

Wall Area

below (ft2)

Wall

Weight

below

(kips)

Wall Seismic

Weight (kips)

Wall height

below floor

level (ft)

Wall height

tributary to

each floor level

(ft)

Wall Area

below (ft2)

Wall

Weight

below

(kips)

Wall

Seismic

Weight

(kips)

Wall height

below floor

level (ft)

Wall Area

below

(ft2)

Wall

Weight

below

(kips)

Wall Seismic

Weight (kips)Length (ft)

Trib. Wall

Height

[above &

below]

(ft)

Glass

Seismic

Weight

(kips)

Total

Seismic

Weight

(kips)

Roof 4,284 11,655 0 0 0 0 0 44 125 103 128 144 137 114 10.5 1,648

Parapet 3.00 3.00

Attic 0 0 2,142 11,858 0 0 0 44 125 103 128 144 137 114 14.83 10.42 1,121 1,995 1,401 14.83 10.42 231 514 361 14.83 318 801 400 64 10.42 10 3,911

Second Floor 0 0 0 0 14,000 0 0 44 125 103 128 144 137 114 18.50 16.67 1,063 2,359 2,177 18.50 16.67 217 603 559 18.50 292 918 859 102 16.67 26 5,633

First Floor 0 0 0 0 0 10,403 3,597 44 125 103 128 144 137 114 11.50 15.00 1,982 2,736 2,547 11.50 15.00 301 519 561 11.50 474 927 923 43 15.00 10 5,878

Basement

Notes:

1 - Roof height is the average between the top of parapet and top of steel truss supporting the skylight. 17,070

2 - Seismic base is at basement level.

3 - Wall weight includes area of exterior brick walls with shotcrete.

4 - The exterior stone cladding is granite. Weight of 170 pcf is assumed.

5 - Glass weight includes area of exterior windows with an assumed weight of 15 psf.

Floor Area (ft2)

1Floor Weight (psf) Brick Wall Weight

3Exterior Glass Weight

5Shotcrete Wall Weight

3Stone Cladding Weight

4


Period

Ct= 0.02

hn (ft)= 58.33

B= 0.75

T= 0.42 sec

Notes:

1- The period calculated per ASCE 41-17 Equation 4-4.

2- Ct and B are for "all other framing system" per ASCE 41-17 Section 4.4.2.4.

3- The roof height is the average between the top of parapet and top of steel truss

supporting the skylight.


Site Parameters

Period Sa

0 1.2636

0.06 3.159

0.30 3.159

0.55 1.733

0.80 1.194

1.00 0.960

1.25 0.768

1.50 0.640

1.75 0.549

2.00 0.480

2.25 0.427

2.50 0.384

2.75 0.349

3.00 0.320

3.25 0.295

SXS = 3.159 g

SX1 = 0.960 g

To = 0.06 s

Ts = 0.30 s

Sa= 2.274 g

T = 0.42 s

Notes:

1- Site Specific spectral accelerations based upon soil type and rock profile are provided in report "2015 Update to the Site-Specific Seismic Hazard

Analyses and Development of Seismic Design Ground Motions, UC Berkeley, 15 July 2015 by URS Corporation. Procedure as specified in ASCE 7-16,

Section 21.4 is used to develop Design Response Spectrum shown above.

2 - In closest boring near Doe Memorial Library and the Moffitt Library, rock is 10 ft below grade.

0

0.5

1

1.5

2

2.5

3

3.5

0 0.5 1 1.5 2 2.5 3 3.5

Sp

ect

ral A

cce

lera

tio

n (

g)

Period (sec)

BSE-2E Response Spectrum


Seismic Force Distribution

Sa= 2.27

W= 17,070 kips

C= 1.0

Per ASCE 41-17

Table 4-7

V= 38,820 kips

k= 1.00

Floor Levels Story Height Total Height, H Weight, W W x Hk

coeff Fx Story Shear, V

(ft) (ft) (kips) (kips) (kips)

Roof 13.50 58.33 1,648 96,145 0.19 7,346 7,346

Attic 14.83 44.83 3,911 175,359 0.35 13,398 20,744

Second Floor 18.50 30.00 5,633 168,995 0.33 12,912 33,655

First Floor 11.50 11.50 5,878 67,594 0.13 5,164 38,820

Basement

58.33 17,070 508,092 1 38,820

Notes:

1- Base of building is assumed to be at Level 1 which is at grade. Partial basement is ignored.

2- Modification Factor, C, per ASCE 41-17, Table 4-7

Per ASCE 41-17 Section 4.4.2.2, K = 1.0 for periods less than

0.5 sec and K = 2.0 for T >2.5 sec. It varies linearly in

between 0.5 sec and 2.5 sec period.


Average Wall Stress Check Under ASCE 41-13 BSE-2E Site Specific Spectra

Average Stresses

Ms = 1.75

Ms = 4.5

f'c = 5000 psi Based upon general notes, Dwg S-1 / 1990

Ms = 4.5

f'c = 2500 psi Assumed per building vintage, ASCE 41-17, Table 10-2

Em = 420 psi See note 2 and 3

Ec = 4287 psi See note 4

Ec/Em = 10.2

Story Story Shear

Masonry

Wall Area

Shotcrete

Wall Area

Shear Force

in Masonry

Walls

Shear Force in

Shotcrete Walls

Average Shear

Stress, Masonry

Walls

Tier 1 Shear Stress

Limit, Clay Masonry

Walls

Masonry Walls

OK?

Average Shear

Stress,

Shotcrete Walls

Tier 1 Shear

Stress Limit,

Shotcrete Walls

Shotcrete Walls

OK?

Concrete Wall

Area

Average Shear

Stress, Concrete

Walls

Tier 1 Shear Stress

Limit, Concrete

Walls

Concrete Walls

OK?

(kips) (in2) (in

2) (kips) (kips) (psi) (psi) (psi) (psi) (in

2) (psi) (psi)

Roof - Attic 7,346 63,359 14,688 2,182 5,164 20 30 OK 78 141 OK

Attic - Second Floor 20,744 63,359 14,688 6,162 14,581 56 30 NG 221 141 NG

Second Floor - First Floor 33,655 62,202 14,242 10,086 23,569 93 30 NG 368 141 NG

First Floor - Basement 38,820 89,802 15,048 14,323 24,497 91 30 NG 362 141 NG

Concrete Walls at basement

First Floor - Basement 38,820 87,610 98 100 OK

Story Story Shear

Masonry

Wall Area

Shotcrete

Wall Area

Shear Force

in Masonry

Walls

Shear Force in

Shotcrete Walls

Average Shear

Stress, Masonry

Walls

Tier 1 Shear Stress

Limit, Clay Masonry

Walls

Masonry Walls

OK?

Average Shear

Stress,

Shotcrete Walls

Tier 1 Shear

Stress Limit,

Shotcrete Walls

Shotcrete Walls

OK?

Concrete Wall

Area

Average Shear

Stress, Concrete

Walls

Tier 1 Shear Stress

Limit, Concrete

Walls

Concrete Walls

OK?

(kips) (in2) (in

2) (kips) (kips) (psi) (psi) (psi) (psi) (in

2) (psi) (psi)

Roof - Attic 7,346 79,196 21,600 1,941 5,404 14 30 OK 56 141 OK

Attic - Second Floor 20,744 79,196 21,600 5,482 15,261 40 30 NG 157 141 NG

Second Floor - First Floor 33,655 70,749 19,296 8,895 24,761 72 30 NG 285 141 NG

First Floor - Basement 38,820 149,606 21,600 15,693 23,126 60 30 NG 238 141 NG

Concrete Walls at basement

First Floor - Basement 38,820 123,840 70 100 OK

Notes:

1- Force distribution between masonry and shotcrete is based upon relative rigidity , Wall Area x Shear modulus = A x 0.4x E.

2- Em = 700 f'm per ASCE 41-17 Section 11.2.3.7 & TMS 402 Section 1.8.2.2.1.

3- f'm = 600 psi for Unreinforced Clay Units per ASCE 41-17, Table 11-2a.

4- Ec = wc1.5

x 33 x sqrt(f'c) per ACI 318 Section 8.5.1.

5- Shear stress in shear walls is per ASCE 41-17, Equation 4-9 where the respective Ms factors for each material are used.

6 - Ms factor per ASCE 41-17 Table 4-8.

Clay URM

Shotcrete

Concrete

Transverse (E-W direction)

Longitudinal (N-S direction)


Average Wall Stress Check Under ASCE 7-10 Site Specific Design Response Spectra

Sa (ASCE 7-10) = 1.71 See Note 3

Sa (BSE-2E) = 2.27

Sa (ASCE 7-10 DBE)/Sa BSE 2 = 0.75

R = 4 Detailing is equivalent to an Ordinary Bearing Wall System

Story

BSE-2E

Story Shear

ASCE 7-10

Story Shear

Shotcrete Wall

Area

Shotcrete Average

Shear Stress

Reinforcing

Ratio

Shear Stress

Limit Wall OK?

(kips) (kips) (in2) (psi) (psi)

Roof - Attic 7,346 5,509 14,688 94 0.0037 218 OK

Attic - Second Floor 20,744 15,558 14,688 265 0.0037 218 NG

Second Floor - First Floor 33,655 25,241 14,242 443 0.0037 218 NG

First Floor - Basement 38,820 29,115 15,048 484 0.0028 185 NG

Story

BSE-2E

Story Shear

ASCE 7-10

Story Shear

Shotcrete Wall

Area

Shotcrete Average

Shear Stress

Reinforcing

Ratio

Shear Stress

Limit Wall OK?

(kips) (kips) (in2) (psi) (psi)

Roof - Attic 7,346 5,509 21,600 64 0.0037 218 OK

Attic - Second Floor 20,744 15,558 21,600 180 0.0037 218 OK

Second Floor - First Floor 33,655 25,241 19,296 327 0.0037 218 NG

First Floor - Basement 38,820 29,115 21,600 337 0.0028 185 NG

Notes:

1- Entire story shear is assumed to be resisted by shotcrete only

2 - Reinforcing for 1990 walls is #4@ 12" o.c. e.w, f'c = 5000 psi, φ= 0.60, αc x sqrt (f'c), αc = 2.0 for given wall aspect ratios, fy = 60 ksi per 1990 drawings

3- Wall thickness is 4.5 " above First Floor and 6" below First Floor

4 - Site Specific spectral accelerations are based upon the soil type and rock profile provided in the report "2015 Update to the Site-Specific Seismic Hazard Analyses and Development of Seismic Design Ground Motions,

UC Berkeley, 15 July 2015 by URS Corporation for ASCE 7-10. The procedure as specified in ASCE 7-10, Section 21.4 is used to develop the Design Response Spectrum.

Transverse (E-W direction)

Longitudinal (N-S) Direction

5 - In closest boring near Doe Memorial Library and the Moffitt Library, rock is 10 ft below grade.

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