Laguna Niguel Stairs

Laguna Niguel Stair Replacement

Laguna Niguel Stairs

Project Description

Client: Rancho Sub-Association
Location:  Laguna Niguel, California

Two wooden stairs, supported on concrete pedestals, had been constructed over a graded slope for pedestrians to travel between 2 residential streets. The stairs had been in use for about 20 years. During those years surficial soil had migrated down the slope. Some soil collected against wood framing, eventually resulting in wood rot.

The Challenges

Rancho Sub-Association, the HOA for this Laguna Niguel, CA, neighborhood, asked our company to investigate the condition of the old stairs and design preplacement stairs that would last a long time and be aesthetically pleasing. We were also asked to prepare construction plans, contractor bid packages, review bids, offer our recommendation for contractor, obtain a construction permit with the City of Laguna Niguel, and to provide inspection during demolition of the old stairs and during construction of the two new stairs.

During the investigation of the old stairs the conditions of the existing wood framing and concrete pedestals were assessed. The wood framing was found to be heavily weathered and abundant areas had wood rot, especially at the ends close to, and in contact with, the slope face. Using hand-augers, the embedment depths of the concrete pedestals were determined. Other elements of the stairs were observed and evaluated for reuse.

It was determined that the concrete pedestals were adequate to support new and heavier structures, and that the rest of the stairs were too weathered or under-designed to be structurally sound, except for the concrete landings at the upper and lower terminus ends. Our recommendation to the client was for total replacement, except for the pedestals.

We prepared a stairs repair plan, designing two replacement stairs, one with an overall rise of about 29 feet, and one with a rise of about 20 feet. The surveyed locations of the upper and lower concrete landings and of the tops of the concrete pedestals were the control points for the designs. 3” x 12” urethane-sealed glue-lam beams were specified for the frame members. Short concrete block retaining walls were designed under the stairs to protect the glue-lam frame from contact with the dirt slope. Pre-cast lightweight concrete steps were specified for the stair risers, and components by Trex, a decking material company, were specified for the railings. The Trex elements are made from recycled plastic, reclaimed sawdust, and a binder material, making them eco-friendly and highly resistant to weathering. The construction plan was reviewed and approved by the City Building Department.

With an approved repair plan in hand, our company prepared contractor bid packages for the construction and solicited various local contractors to submit bids for the work. Construction bids were reviewed, and at our recommendation, Seashore Construction, Inc., of Santa Ana was awarded the contract.

La Floresta

La Floresta
LaFloresta

Project Description

Client:   Chevron Land Development
Location:   Brea, California
Surface Area: 124 acres

La Floresta was a Chevron Land Development project in Brea, California, that comprised approximately 124 acres in what was once Unocal’s Hartley Center research facility and Manassero Farms. The site was developed primarily as a community of single family detached homes, courtyard homes, condominiums, and apartments. The project required more than 14 years to complete. Albus & Associates, Inc. (AAI), was involved from the beginning, during site characterization and feasibility studies, to final paving of the streets.

The Challenges

Challenges encountered and overcome during site development included demolition of the research facility, including oil processing systems, abandonment of oil wells, removal and remediation of soil impacted by oil production contaminants, protection of a live 96-inch-diameter MWD water line, and the typical daily challenges of grading the site and the construction of the residential structures and associated improvements. AAI was there every step of the way.

Grading the site required the removal of contaminated soil and surficial soil deemed unsuitable to support the proposed improvements. Removals and filling of excavations were accomplished using heavy equipment.

AAI geologists monitored and mapped removals and our field technicians monitored fill operations and performed field density testing to assure adequate compaction criteria was being met.

One of the biggest challenges was protecting an existing 96-inch-diameter MWD water line that was to have up to 5 additional feet of fill placed over it. AAI investigated the soil conditions around and under the pipe and determined that earth materials below the pipe were prone to consolidation under the weight of the additional fill. AAI designed a system that replaced up to 8 feet of existing soil over the pipe with geo-foam, reducing the weight of the existing materials over the pipe and allowing the safe placement of additional fill to design grades. The geo-foam system incorporated elements to prevent the trapping of water under the foam. The client was pleased with the outcome and a paved road into the development has been constructed over the geo-foam.

OMYA, Inc.

OMYA Inc.
OMYA Inc.

Project Description

Client:  OMYA, Inc.
Location:  Lucerne Valley, California
Project: OMYA Mine

Our firm was contacted by OMYA, Inc., to help them with mitigating a safety issue at one of their calcium carbonate surface mines in Lucerne Valley. To satisfy the safety requirements of their mining permit OMYA needed to provide minimum haul road widths for their 50-ton and 100-ton rock trucks that transported crushed materials from the mine to their processing facility. There was an area approximately 160 feet long at one of their haul roads where the width was not wide enough and the topography above and below the road was too steep to safely grade the road wider. We were asked to assess the area and come up with a means to widen the road from the existing 15 feet to the required minimum width of 20 feet and provide a required 4-foot-tall berm along the downhill side.

The Challenges

Working with HI-TECH Rockfall Construction Inc., a plan was developed to accomplish the road widening by constructing a retaining system along the downhill side of the road. The retaining system used 7-inch-diameter, 0.75-inch-thick, steel pipe posts, embedded in drilled holes at least 5 feet into solid rock, connected with 0.75-inch-thick wire rope. The space between posts were faced with wire rope net by Geobrugg that was covered with Tencate Mirafi filter fabric. To prevent overturning, each post was anchored in front with wire rope tie-back struts anchored in drilled holes. Posts and anchors were secured in the drilled holes using 6,000 psi non-shrink Rapid Set grout.
At the upper end where the retained height exceeded 15 feet, the post tie-back struts were anchored to an 8-foot by 20-foot, 1-inch-thick steel plate that was buried after connections were made.

The retained height ranged from 8.5 to 21 feet from competent rock to top of berm. HI-TECH Rockfall Construction Inc. completed the construction of the retaining system and grading of the road in front of it. We had an engineer on site every day to verify embedment depth of the posts and to monitor the various stages of construction. The result was a semi-temporary robust retention system that help up the widened portion of the haul road and the berm.
Challenges were faced daily during construction. The greatest challenges were safety issues, and after just a few hours on the side of the giant hillside one realized that there are many hazards and constant vigilance was required.
Falling rocks from the 240’ high rock face above the road was a constant hazard. To minimize rock falls, HI-TECH personnel rappelled from the top to bottom and removed loose rocks before any work started on the road. Still, rocks occasionally fell, and personnel were reminded to stay on the outside of the road whenever possible.

The hazard of working along the outside of the road was falling over the edge. The descent to the bottom of the steep hillside was about 130 feet. HI-TECH had a crew member dedicated to watching the others working along the edge.

The nature of the calcium carbonate rock and soil presented a few unique hazards. Being predominately white, the soil and rock faces reflected the sun quite well and fatigued the eyes and beat on exposed skin. This was an issue until about 2 PM when the sun moved behind the ascending rock face. Sunglasses, long-sleeved shirts, and sunblock helped. The crystalline nature of the rock and soil made it very sharp, which would cause abrasions to exposed skin in a fall, even from the dust from the almost constant wind. Wearing gloves and long-sleeved shirts helped to protect against this.

OMYA had their own safety protocols for vehicles traveling on the 5 plus miles of the haul road between their office facility and the work site. All vehicles were required to sign in at the office and check out a radio to broadcast their location at every mile marker. Rock trucks traversing the haul road would request vehicle to stop in turnouts at designated mile markers until the truck passed. Radios were turned in and vehicles signed out at the end of each day. At the work site, a blast of the horn would notify the crew that one of the massive trucks was about to drive though the area, and all work would stop until the truck had moved on.

Signal Hill

Signal Hill Petroleum Company

Signal Hill
Signal Hill

Project Description

Client: Signal Hill Petroleum Company
Location: Signal Hill, California
Project: Fault Investigations

Signal Hill has a long history of oil production, and a longer history of bedrock faulting. This firm has been investigating fault locations since 1999, when we were the Geotechnical firm of record during development of the hilltop from oil fields to residential homes by Comstock, Crosser & Associates. In the years since we have investigated numerous properties for the Signal Hill Petroleum Company and for private owners of properties wanting to develop their properties. Fault studies provided the property owners the locations of active and inactive fault locations, or the absence of faults, on their properties so that they could design their site development with safe buffer zones between the faults and proposed habitable structures. After years of fault investigations by us and various other geotechnical firms, we developed the composite Fault Location Map presented below for the Signal Hill Petroleum Company, a major owner of properties in Signal Hill, so that their planning team can anticipate the limitations that active faults may present on their properties not yet developed.

The Challenges

A typical fault trench investigation involved the excavation of trenches semi-perpendicular across the anticipated location and trend of a fault. These trenched were excavated with excavators to depths of 20 feet or more, with the sides laid back and benched to provide safe access for our geologists. The trench sidewalls were cleaned off to expose the geologic formations and characteristics that showed the history of ancient and near geologically recent activity.

Our geologists painstakingly mapped, with pencil on graph paper, at least one sidewall of the trench, concentrating on areas showing faulting and fracturing, and on areas near surface which might give clues to how recent of how far in the past the faulting and fracturing occurred. The field trench logs were then illustrated using AutoCad to produce the graphic trench logs like the one shown here.

As shown on the FT-4 trench log above, main fault traces can be identified by having different bedrock units on either side of a fracture, such as San Pedro Formation of the left side and Lakewood Formation on the right side of the Cherry Hill Fault Main Trace. Other identifying evidence could be the offset of sand and gravel beds, offset of near surface features such as krotovinas (infilled rodent burrows). The development of argillic soil horizons, which in a simple definition is the weathering of bedrock into soil, can give an indication of how long ago a fracture occurred. Our firm has employed experts in determining the age of argillic soil to visit the site and determine if a fault can be considered inactive or not. This can be a very important determination. A fault considered active required a structural setback restricting the construction of habitable structures, where a fault considered inactive would not require any restrictions.

When mapping and assessment has been completed, the trenches are backfilled using the materials excavated from the trenches, The backfill is placed in moisture-conditioned and compacted lifts of about 8- to 12-inches in thickness. A soil technician from our firm observes the backfill operations and performs field density tests to demonstrate that the backfill in properly compacted.

Unocal Land Development

Unocal Land Development

Unocal Land Development

Project Description

Client: Unocal Land Development
Location: Fullerton, CA
Project: Rehabilitation of E. Bastanchury Road

Bastanchury Road is a 4-lane arterial roadway traversing through the city of Fullerton, CA.  Extensive development along this corridor resulted in a significant increase in traffic volume above the original design criteria.  As a result, portions of this important transportation route became structurally damaged and required rehabilitation.  A section of roadway approximately 1 mile in length was selected for evaluation and rehabilitation in connection with a proposed residential project.

The Challenges

Albus & Associates, Inc., was retained to perform a comprehensive evaluation of the existing roadway in order to develop recommendations for rehabilitation.  Our evaluation consisted of visual observations of the pavement conditions to record types and extents of damage to the pavement.  The pavement was then evaluated by performing a falling-weight deflectometer test to measure the pavement’s resistance to traffic loads.  This test was followed by coring of the existing pavement and sampling of the underlying soils.  With the data gathered, the roadway was divided into zones with similar conditions and overlay rehabilitation was developed.  During construction, representatives of Albus & Associates, Inc., were present to observe and test the contractor’s work to verify compliance with our recommendations.  Asphaltic concrete was checked for thickness, temperature, and in-place relative compaction.  Construction materials were sampled and then tested in our laboratory facilities to verify compliance with required specifications.

Centex Homes

Centex Homes

Centex Homes

Project Description

Client: Centex Homes/ San Bernardino County Flood Control District
Location: Fontana, CA
Project: Hawker-Crawford Flood Control Channel

The Hawker-Crawford Channel is located in the city of Fontana and consists of approximately 2 miles of concrete box and open trapezoidal channel.  The project extends the storm drain box in Summit Avenue and Frontage Road to San Bernardino Flood Control Basin No. 5.   The project also included the construction of several levies to divert drainage from local tributaries of Lytle Creek to the Hawker-Crawford Channel.

The Challenges

Albus & Associates, Inc., was retained to prepare a soils investigation of the project area that was used in the design of the Hawker-Crawford channel and associates levies.  This investigation included numerous backhoe test pits and borings to examine the underlying soil conditions and collect soil samples for laboratory testing.  Samples were tested in our laboratory to determine engineering characteristics and design parameters.  

During construction, representatives of Albus & Associates, Inc., were present to observe and test the contractor’s work for compliance to our recommendations.  Our services consisted of providing soils engineering and materials testing for construction of the channel and associated levies.  Our services included verification of suitable ground for support of the structures; inspection and sampling of fresh concrete placed for the box and trapezoidal structures, preparation of concrete compression specimens, performing concrete compression tests to verify specified strengths, and observation and testing of the structural backfill placed around the structures and levies.

Interstate 15 Sewer and Water Undercrossing

Interstate 15 Undercrossing

Interstate 15 Sewer and Water Undercrossing

Project Description

Client: Centex Homes/Elsinore Valley Municipal Water District.
Location: Lake Elsinore, CA
Project: Interstate 15 Sewer and Water Undercrossing at Third St., Lake Elsinore

The I-15 undercrossing project involved 417 feet of sewer and water at the terminus of Third Street in the city of Lake Elsinore.  Installation of the lines was prompted by large residential developments by Centex Homes east of the freeway that required connection to existing infrastructure west of the freeway.  The crossing involved the installation of 44-inch steel casing for a 30-inch ductile-iron water line and 30-inch steel casing for a 15-inch PVC sewer line.  The casings were installed using a jack and bore method.  The jacking pit was located westerly of the Caltrans right-of-way at the terminus of Third street while the receiving pit was located easterly of the right-of-way.  The lines were installed nearly 40 feet below the travel lanes of I-15.

The Challenges

Albus & Associates, Inc., was retained to investigate the proposed jack and bore alignment in order to characterize the subsurface conditions and develop design recommendations.  Our investigation included exploratory borings and laboratory testing of representative soil samples.  Our analyses of data included estimation of potential ground displacement and distortion in the travel lanes overlying the proposed alignment, shoring parameters, temporary excavation stability, and corrosion. 

Albus & Associates, Inc., also provided services during the installation process.  During the boring, samples of drill cuttings were evaluated to verify soil conditions were as anticipated in our investigation.  Survey points were established on the travel lanes and monitored by a land surveyor.  The data was provided to our office for review to verify ground subsidence was within tolerable limits. Field representatives of Albus & Associates were present during grouting of the annular space outside the carrier pipes to verify compliance with project specifications.

Alexan Pacific Grove

Alexan Pacific Grove

Alexan Pacific Grove

Project Description

Client: Trammel Crow Residential
Location: Orange, CA
Project: Alexan Pacific Grove Residential & Retail Project

Recently featured as one of the top 10 projects in Southern California in the magazine Real Estate & Construction Review”, the Alexan Pacific Grove project is a mixed-used redevelopment in the city of Orange, California.  The project includes approximately 200 luxury residential units and 12,000 square feet of retail space.  The complex consists of a four-story residential/retail structure surrounding a 6-level integrated parking garage.

The Challenges

Albus & Associates, Inc., was retained to perform a geotechnical investigation of the site for use in design of proposed development.  Our work included drilling of 5 borings and laboratory testing of representative soil samples.  A key issue requiring careful evaluation was differential settlements between the relatively large foundations supporting a heavy parking structure and the smaller, lighter residential foundations located immediately adjacent to the parking structure. Our geotechnical report provided recommendations for design and construction including parameters for heavily-loaded shallow spread footings, ground preparation and fill placement, underground utilities, and pavement.

During construction, representatives of Albus & Associates, Inc., were present to observe and test the contractor’s work to verify compliance with our recommendations.  Our services consisted of providing observation and testing during the preparation of ground, placement of compacted fill for general grading and utility trench backfill, compaction of paving subgrade, and placement of pavement materials.

182nd Street Bridge Expansion and Seismic Retrofit

182nd Street Bridge Expansion

182nd Street Bridge Expansion and Seismic Retrofit

Project Description

Client: City of Los Angeles
Location: Los Angeles, CA
Project: 182nd Street Bridge Expansion and Seismic Retrofit

The 182nd Street Bridge was built in 1964, and was recently upgraded to meet the current seismic codes.  The Bridge is 35-foot-wide and 226 feet in length, a 3-span (max span 74 feet) pre-tensioned concrete I- Girder construction, simply-supported on concrete pile foundations. 

The Challenges

Albus & Associates, Inc., was retained to evaluate and redesign a deep foundation system using 48-inch-diameter Cast-in-drilled-hole (CIDH) piles as part of the value engineering (VE) services.  We performed analyses for vertical and lateral pile capacities under static and seismic conditions. 

Our services also included observation, testing and consultation during construction of eight CIDH piles, four at each abutment.  Our staff logged the drilled holes to confirm subsurface conditions and to verify design assumptions.  We observed the installation of inspection pipes and concrete placement in accordance with project plans and specifications.  After concrete placement, we performed Gamma Gamma Logging (GGL) services through the pre-installed inspection pipes to verify concrete quality and pile integrity, and prepared a construction report summarizing our findings and test results.  

Xcelerator Amusement Attraction

Xcelerator Amusement Attraction

Xcelerator Amusement Attraction

Project Description

Client: Knott’s Berry Farm
Location: Knott’s Berry Farm, CA
Project: Xcelerator Amusement Attraction

The Xcelerator is a high-speed thrill ride at Knott’s Berry Farm.  The ride hydraulically launches a train holding 20 passengers to reach a top speed of 82 mph in 2.3 seconds.  The train travels through a vertical 205-foot ascent and immediate descent at a 90-degree angle.  The track encompasses a total of 2,201 feet.  The extreme speeds and changes of direction produce relatively large forces on the supporting pile foundation system.

The Challenges

Albus & Associates, Inc., was retained to investigate the site to characterize geotechnical conditions and provide design parameters.  Our investigation included drilling borings to a maximum depth of 50 feet and selected sampling of soils encountered.  Our recommendations included design parameters for single and group capacities of free- and fixed-head piles.  Each side of the tower required a pile group consisting of 20 piles in a non-symmetrical configuration.  

During construction, representatives of Albus & Associates, Inc., were present to observe and test the contractor’s work to verify compliance with our recommendations.  Our services consisted of providing soils engineering and materials testing for construction of the ride foundations, queue station, and other site improvements.  Our services included observation of excavations for CIDH piles, inspection and sampling of fresh concrete placed for the CIDH piles, preparation of concrete compression specimens, performing concrete compression tests to verify specified strengths, and observation and testing of structural backfill placed for utilities and around structures.