Richmond/San Rafael Bridge

HIGH CAPACITY MICROPILE

CONSTRUCTION

AGRA Foundations, Inc.

Completed in 1956, the 5.5 mile long bridge sits between two fault lines in the San Francisco Bay.

The bridge connects the cities of Richmond and San Rafael as part of Interstate 580.

Richmond/San Rafael BridgeRichmond/San Rafael Bridge

Photograph courtesy of California Department Transportation

Site LocationSite Location

Richmond/San Rafael Bridge

San Francisco

HA

YWAR

D FAU

LT

HAYW

ARD

FAULT

SA

N A

ND

RE

AS FA

ULT

SA

N AN

DR

EA

S FA

ULT

Project HierarchyProject Hierarchy

Date bid:

August 08, 1999Owner:

California Department of Transportation

General Contractor:

A Joint Venture of Tutor Saliba/Koch/Tidewater

Prime Subcontractor:

AGRA Foundations, Inc.

AGRA’s Scope of WorkAGRA’s Scope of Work

``

66” Dia. CIDH Piles

150” Dia. CIDH Piles

Substructure Micropiles

Superstructure Micropiles

Substructure MicropilesSubstructure Micropiles

Pile Data Micropiles This table

represents 31 pier locations

with 476 production piles

and 5 performance

piles.Load range

from 290 kips to 1140 kips

Substructure MicropileSubstructure Micropile

Note Spirals at base of pile and rings at Micropile top (inside the bell)

Typical CRIP

Prerequisites to MicropilesPrerequisites to Micropiles

Work Platforms

Micropile Installation TemplatesMicropile Installation Templates

Hinge Locations

Templates were constructed to accurately locate the micropiles

Micropile Installation TemplatesMicropile Installation Templates

Completed Templates and Completed Templates and Conductor CasingConductor Casing

Templates in place on Bridge

Template Connector

Micropile InstallationMicropile Installation

Conductor Casing

Rubber Seat

Bell

Coring

Grooving

Pipe placed from bottom of bell and socketted into bedrock (not shown)

Foundation Bell

Steel Bell Casing

Pipe Reinforcement

14” Dia. Cored Holewith Groves

Seal

Bed Rock

Bedrock Socket

Mud line

PermanentSteel Casing

12” Dia.

Geological DescriptionGeological Description

The Franciscan Formation is a heterogeneous unit of sedimentary and volcanic rock deposited in an offshore, deep-marine trough at the base of the continental slope. The formation consists of massive graywacke sandstone, dark shale, minor chert and limestone, altered volcanic rock, and various metamorphic rocks. All of the rock is intruded by serpentine. The Franciscan Formation is believed to be as thick as 50,000 feet and typically found as fault-bound blocks accreted onto the western shoreline of California by plate movement .

Bed Rock Topographic Contours

Log of Test BoreLog of Test Bore

Working Drawing Load Capacity Calculations

Micropile TestingMicropile Testing

Micropile TestingMicropile Testing

Load Test Result SummaryLoad Test Result Summary

Construction MethodsConstruction Methods

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