CA_FLAP_CRS4018(1)_Whitney_Portal_Final_Geotech_Report_-_March_2015.pdf

WHITNEY PORTAL ROAD

CA FLAP CRS4018(1)

FINAL GEOTECHNICAL REPORT

Report # CA-FX-4018-15-01

Geotechnical Section

Technical Services Branch

March, 2015

Table of Contents

SECTION ONE--INTRODUCTION

1.1 SITE CONDITIONS

1.1.1 Segment 1 Station 99+50 to 279+00

1.1.2 Segments 2 and 3 Station 297+00 to 690+75

1.2 PROPOSED CONSTRUCTION

1.3 OBJECTIVE AND SCOPE

SECTION TWO--GEOLOGY AND SEISMICITY

2.1 GEOLOGY

2.1.1 Regional Geology

2.1.2 Site Geology

2.2 GEOLOGIC HAZARDS

2.3 SEISMICITY

2.4 SEISMIC DESIGN PARAMETERS

SECTION THREE—FIELD INVESTIGATION

3.1 ROCKFALL OCCURANCE

3.2 SUMMARY OF SUBSURFACE EXPLORATION

3.3 LABORATORY TESTING

SECTION FOUR RCOMMENDATIONS

4.1 ROCKFALL MITIGATION ALTERNATIVES

4.2 ROADWAY REALIGNMENT AND ROCKFALL CATCHMENT DITCHES

4.2.1 Alignment Shifts

4.2.2 Engineered Catchment Ditches

4.3 SLOPE SCALING

4.3.1 SLOPE ROUNDING

4.4 SHOULDER STABILIZATION

4.5 CUT SLOPE RECOMMENDATIONS

4.6 SUBEXCAVATION

4.7 CORROSION

4.8 SHRINK/SWELL RECOMMENDATIONS

4.9 SPECIFICATIONS

4.10 LIMITATIONS

SECTION FIVE -- REFERENCES

TABLES

TABLE 1: FAULT DATA

TABLE 2: SUMMARY OF SEISMIC PARAMETERS CORRECTED FOR SITE CLASS C

TABLE 3: SUMMARY OF SOIL CLASSIFICATION INDEX TESTS

TABLE 4: RECOMMENDED ROCKFALL MITIGATION ALTERNATIVES

TABLE 5: SUMMARY OF EXISTING PERCENT ROCKFALL CONTAINMENT TO

PROPOSED PERCENT ROCKFALL CONTAINMENT

TABLE 6: ESTIMATED SCALING EFFORT AND QUANTITY

TABLE 7: RECOMMENDED CUT SLOPE RATIOS BY STATION

FIGURES

FIGURE 1: PROJECT LOCATION AND SITE MAP

FIGURE 2: GEOLOGIC MAP OF THE WHITNEY PORTAL ROAD PROJECT AND THE

SURROUNDING REGION

FIGURE 2.1: DESCRIPTION OF GEOLOGIC UNITS

FIGURE 3: GENERAL SLOPE GEOMETRY USED IN THE RCAD ANALYSIS

FIGURE 4: PHOTOGRAPH OF TYPICAL EXISTING DITCH CONDITIONS

APPENDICES

APPENDIX A: GEOLOGIC MAP AND LEGEND

APPENDIX B: LABORATORY TEST RESULTS

APPENDIX C: PHOTOGRAPHIC DEPICTIONS OF SLOPE SCALING LOCATIONS

APPENDIX D: ROCK FALL AREA CATCHMENT DATA

SECTION ONE--INTRODUCTION

This report presents the geotechnical engineering study and recommendations pertaining to the rockfall issues, erodible embankments, proposed alignment, cut slope recommendations, and roadway subexcavation locations on the Whitney Portal Road, CA CRS FLAP 4018(1) project.

The project limits begin just east of the Whitney Portal trailhead at an approximate elevation of

8300 feet and continues east 11.2 miles toward the town of Lone Pine, CA down to an approximate elevation of 3700 feet. The roadway is the primary access route to Mount Whitney in the Inyo National Forest and the Alabama Hills managed by the Bureau of Land Management

(BLM). Outside Inyo National Forest the roadway is managed by Inyo County. Figure 1 displays the project location and site map.

FIGURE 1:- Project Location and Site Map

1.1 SITE CONDITIONS

1.1.1 SEGMENT 1 STATION 99+50 TO 279+00

From the beginning of the project at station 99+50 just east of the Whitney Portal trailhead parking area the roadway descends down a series of hair pin-turns confined to an average 22-foot paved section. Significant roadway cut slopes are present in both granitic bedrock and colluvial overburden with 1-5 foot boulders common (boulders up to 12 feet are also present in some locations). The bedrock is homogeneous and cut near-vertical in many locations. Generally, cut slopes in colluvial overburden range from 30 to 100 feet in vertical height with slope angles of

35 to 65 degrees. These unconsolidated cuts and native slopes are known to produce regular rockfall and are a continual maintenance issue requiring removal of fallen rock from the roadway and roadside ditches. Evidence of rockfall can be seen as divots in the existing asphalt surface or the presence of relatively new asphalt patches repairing damaged sections. Over-steepened outboard embankment slopes are common and are highly erodible. Roadway drainage is poor and frequently runs unimpeded over the outboard slopes leading to localized erosional rivulets encroaching the roadway. The subgrade material is typically comprised of a few feet of loose sand and gravel with cobbles and boulders up to three feet in diameter overlying granite bedrock.

Bedrock may be directly below the pavement surface in some areas as described in the CFLHD

Pavements and Materials Report Dated June 2014 (Report #14-02).

1.1.2 SEGMENTS 2 AND 3 STATION 297+00 TO 690+75.

As the roadway enters the Owens Valley floor the project has been divided into Segments 2 and

3. Within these segments the embankments are relatively stable with minor shoulder erosion from poor surface drainage. Several cuts are up to 40-feet tall and are comprised of boulders varying in size and up to 5-feet in diameter in a sand, gravel and cobble matrix. Although these slopes are over-steepened (up to 70 degrees in some locations); they are considered relatively stable due do the partially cemented matrix and grain-to-grain contact of the cobbles and boulder material. The roadway subgrade soils consist mainly of loose sand, gravels, cobbles and up to boulder-sized material as described in the CFLHD Pavements and Materials Report Dated June

2014 (Report #14-02).

1.2 PROPOSED CONSTRUCTION

The Federal Highway Administration (FHWA) Central Federal Lands Highway Division

(CFLHD), in cooperation with the Inyo National Forest, Bureau of Land Management and Inyo

County is proposing the roadway receive a 3R construction treatment (restoration, resurfacing and rehabilitation) including minor amounts of roadway widening, grading and drainage improvements. The proposed construction will also include minor amounts of scaling, shoulder stabilization, subexcavation, and alignment corrections identified during the 30 percent field review.

1.3 OBJECTIVE AND SCOPE

The objectives of this study are specifically to develop recommendations concerning rockfall-prone slopes, shoulder stabilization, cut slope recommendations, and roadway subexcavation areas identified during the 30 percent field review. In accomplishing these objectives, the scope of work included field exploration and sampling, correlation of available data, engineering analysis, and recommendations. The field exploration included visual site reconnaissance, surface hand sampling and lab testing.

SECTION TWO--GEOLOGY AND SEISMICITY

2.1 GEOLOGY

2.1.1 REGIONAL GEOLOGY

Whitney Portal Road is located on the eastern edge of the Sierra Nevada geologic province near the transitional zone with the Basin and Range geologic province to the east. The Sierra Nevada is comprised of a single large westward tilted granitic batholith, predominantly of Jurassic and

Cretaceous age characterized by steep slopes and granitic rock. A batholith is an intrusive igneous rock that is formed by magma cooling slowly at depth. This is the result of a subduction zone along California’s coast wherein the Pacific plate sank under the less dense North American plate, heating the subducted plate at depth and producing magma that ascended through the overlying lithosphere. These granitic rocks are primarily granite, granodiorite, quartz diorite and monzonite of various degrees of weathering.

During the last 10 million years, at least four periods of glacial advance have coated the mountains in a thick mantle of ice. Today, a few small glaciers remain representing the southern-most glaciers in North America. The extensive history of glaciation within the range coupled with the erosion resistant nature of the granitic rocks that make up most of the Sierra Nevada have created a landscape of hanging valleys, towering waterfalls, craggy peaks, alpine lakes and gigantic glacial canyons.

The Sierra Nevada Range is still growing today gaining height during earthquakes near Bishop and Lone Pine. Rain and winter snows combined with the steep character of the landscape create an environment that includes massive movements of sediment and rapid erosion. The mountains are being removed by erosion almost as quickly as they grow. This erosion has created and deposited sediments thousands of feet thick on the floor of the nearby valleys.

2.1.2 SITE GEOLOGY

From the beginning of the project at station 99+50 the roadway traverses steep terrain comprised predominantly of Quaternary-aged colluvial deposits of small to large boulders in a sand and gravel matrix overlying Late Cretaceous-aged dark granodiorite to approximate station 279+00.

Here at station 279+00 the Sierra Nevada Frontal Fault has thrust the granitic bedrock of the

Sierra Nevada’s above the alluvial and debris flow deposits which comprise the floor of the

Owens Valley. Heading east (up-station) the roadway crosses alluvial and colluvial deposits predominantly comprised of cobbles and boulders (5-foot boulders are common) in a sand and gravel matrix. Throughout the bottom third of the alignment the roadway passes through the

Alabama Hills; a pale-pink, medium-grained biotite monzogranite. Near the end of the project outcrops from lower part of the Alabama Hills are present and are described as a volcanogenic sedimentary subunit with rhyolite tuff. The outcrop of this unit (near station 640+00) is highly fractured with adversely oriented jointing daylighting to the roadway Figure 2 displays the proposed alignment superimposed upon the USGS Geologic Map of the region .

Figure 2: Geologic Map of the Whitney Portal Road Project and the Surrounding Region

2.2 GEOLOGIC HAZARDS

Geologic hazards exist from both the natural environment of the project sites and from existing and proposed construction of the roadway. The main geologic hazards that may exist within the vicinity of the project limits include:rockfall, erodible granular soils, seismic events, and debris flows. Rockfall, in particular is likely to be encountered during construction along the route.

Section 3 discusses the rockfall along the route and Section 4 of this report discusses short-term and long-term rockfall mitigation alternatives.

2.3 SEISMICITY

The Whitney Portal Road Project area is located in an active seismic region. The closest active faults to the project site are listed in Table 1, Fault Data. The major fault zones within a 40-mile range to the project location are the, White Mountains Faults, Birch Creek Faults, and Panamint

Valley Faults. The faults that cross within the project limits are the Independence Faults, Owens

Valley Faults, Hunter Mountain Connected Faults, and Southern Sierra Nevada Faults. These faults are strike-slip to normal with slip-rates of 0.004 to 0.10 inches per year, (0.1 to 2.5 millimeters per year) and vary in length from 10 miles, as seen in the Birch Creek faults, to 116 miles in the Hunter Mountain Connected Faults. The overall trend of the faults within 40 miles of the project location is Northwest by Southeast with a dip direction to the east. Table 1 displays the fault data and the Maximum Moment Magnitude of each of these faults.

TABLE 1: – Fault Data

Fault Name Fault Zone

Maximum

Moment

Magnitude

(Mmax)

Distance

From End of project

(Miles)

Approximate

Station Fault crosses

Roadway

Fault Parallel

Slip Rate

(INCH/Year)

Length

(Miles)

Age

(years)

Owens Valley/

Lone Pine

Owens

Valley (1)

7.3 0.1 to 0.5 683+00 0.06 53 < 150

Independence

Sierra

Nevada

Frontal

7.2 1.0 279+00 0.01 30 < 15,000

Hunter

Mountain

Connected

Sierra

Nevada

7.6 8.6 279+00 0.10 116 < 15,000

Southern Sierra

Nevada

Sierra

Nevada

7.5 16.7 279+00 0.004 70 < 15,000

White

Mountains

Inyo-White

Mountains

7.4 18.2 N/A 0.04 69 < 15,000

Birch Creek Owens

6.6 18.5 N/A 0.03 10 < 15,000

Panamint

Valley

Owens

7.4 23.6 N/A 0.10 68 < 15,000

Notes:

(1) These fault zones are shown on Figure 2- Geologic Map of the Whitney Portal Road Project Map and the Surrounding

Area

2.4 SEISMIC DESIGN PARAMETERS

Recommended seismic response parameters for the Whitney Portal Road Project design are based on the (AASHTO) LRFD Bridge Design Specifications, 6th edition, 2012, and represents horizontal peak ground acceleration (PGA) with 7 percent probability of exceedance in 75 years

(approximately 1000-year return period). The 1000-year return period uniform hazard spectrum for the Whitney Portal Road Project site was taken at the end of the project just outside the town of Lone Pine, located at 36.60404º N latitude and -118.065º W longitudinal, was obtained in accordance with the AASHTO ground motion maps for the probabilistic horizontal acceleration values corresponding to specific peak ground acceleration (PGA) and the spectral coefficients, namely the short- and long- period ground acceleration (Ss and S1 respectively) and corrected for the soil profile at the end project.

Ground motions caused by earthquakes are influenced not only by the distance from the fault planes, but also by the geology and soils found at the site. Subsurface profiles similar to the ones within the project, with soil layers overlaying bedrock that significantly differ in stiffness and density, will have amplified ground motions and a resonant period governed by the layer thickness and shear wave velocity of the materials. The damage potential of strong ground motions with respect to a structure is typically affected by the period of the strong earthquake motion and the resonant period of both the soil and the structure. Based on the material within the Owens Valley, the average time-weighted shear wave velocity for the top 100 feet (VS100) of subsurface materials was estimated between 1,200 and 2,500 feet per second. Therefore, the site is classified as Class C according to the site class definitions specified in Table 3.10.3.1-1 of

AASHTO.

The recommended spectral acceleration coefficient values for probabilistic design with a return period of 1000 years were calculated using the program provided with the AASHTO LRFD

Bridge Design Manual developed by the USGS (2008) entitled “Seismic Design Parameters”, version 2.10 and are summarized in Table 2, Summary of Seismic Parameters Corrected for Site

Class C.

TABLE 2: – Summary of Seismic Parameters Corrected for Site Class C.

Seismic Parameters

Horizontal Peak Ground Acceleration, (As) 0.383g

Horizontal Response Spectral Acceleration at Period of 0.2 sec, (SDs) 0.909g

Horizontal Response Spectral Acceleration at Period of 1.0 sec, (SD1) 0.457g

Site Factor at Zero-Period of Acceleration Spectrum, (Fpga) 1.04

Site Factor at Short-Period Range of Acceleration Spectrum, (Fa) 1.05

Site Factor at Long-Period Range of Acceleration Spectrum, (Fv) 1.50

Based on the long acceleration coefficient SD1 value of 0.457 calculated as Fv.S1, the alignment is assigned to seismic hazard Zone 3 according to Table 3.10.6-1 in AASHTO. Seismic hazard zones reflect the variation in seismic risk in different regions needing different requirements for design as depicted in Table 4.7.4.3.1-1 in AASHTO.

SECTION THREE—FIELD INVESTIGATION

A visual investigation of the slope and roadway conditions was performed during the 30 percent design site visit on April 22 nd and 24 th

, 2014. The investigation involved a visual inspection of the existing roadway elements (rockfall-prone slopes, embankments and roadway surface) as well as the proposed construction’s cut and fill slopes. Hand samples of the soil were taken at various locations during the visual investigation.

3.1 ROCKFALL OCCURANCE

Visual field investigations revealed that rockfall events occurring within the constructed (or engineered) limits along the Whitney Portal Road corridor originate from following two sources:

1. Fractured or jointed rock outcrops where rockfall events can result from freeze-thaw weathering and levering of boulders and blocks from the rock, and the general systematic process of weathering within joints and cracks lead to the eventual movement of slope material. Rockfall produced from these slopes are principally a natural occurrence, emanating higher up on the slopes beyond the original road cuts.

2. Largely unconsolidated slopes deposited from glacial moraines or colluvial slopes where erosion of the soil around boulders contained in a colluvial mass creates rockfall events. In contradiction with the rockfall from the fractured or jointed rock outcrops; rockfall produced from the unconsolidated slopes is primarily from within the man-made roadway cuts. During original construction of the alignment these slopes were cut at an over-steepened angle.

The unconsolidated slopes were identified as the main sources of rockfall identified within the approved program and scope with the funding available and will be the focus of this study.

3.2 SUMMARY OF SUBSURFACE EXPLORATION

A geotechnical subsurface investigation was not performed as there are no proposed structures or significant cuts or fills planed as part of this project. However subsurface data was obtained in

November of 2013 as part of CFLHD pavements investigation which consisted of 45 borings excavated to a maximum depth of 5 feet. Neglecting the cobble and boulder fraction, the pavements investigation revealed the subgrade and embankment materials to be classified as non-plastic gravely silty SAND (SM to SW-SM in USCS). The investigation also reached auger refusal in 15 of the 45 borings within 22 inches of the pavement surface likely due to the presence of cobbles, boulders or near-surface bedrock comprising the subgrade or embankment.

Please refer to the Pavements and Materials Report Dated June 2014 (Report #14-02) including the test results obtained.

During the site visit in April of 2014 two near-surface hand samples were taken to classify potential sources of embankment materials if necessary during construction as well as evaluate cut slope stability. The samples were taken at station 353+50 and 366+50 where a substantial through-cut was shown on the 30 percent design plans. Both samples were taken at the top of an existing cut approximately 40 feet from the existing centerline and within a foot of the surface.

3.3 LABORATORY TESTING

Laboratory testing was conducted on soil samples obtained during the field visit to estimate the materials parameters. Laboratory test procedures and results, along with grain size curves are presented in Appendix B, Laboratory Test Results and summarized in Table 3, Summary of Soil

Classification Index Tests. However due to the nature of the sampling and testing performed, it was impracticable or impossible to incorporate the larger sized material into the sample obtained and it should be made clear that these slopes do contain an estimated abundance of cobbles and boulders (up to 30 percent of the total material) that are not represented in the laboratory summary.

Table 3: Summary of Soil Classification Index Tests

Station Offset Sample Depth (feet) Percent

Passing 200

LL PI USCS AASHTO

353+50 40 FT LT and RT of

Centerline

0-1 11 NV NP SP-SM A-2-4 (0)

366+50 40 FT Right of

Centerline

0-1 19 NV NP SM A-2-4 (0)

Notes: NV = No Value, NP = Non-Plastic, NA = Not Applicable/no test conducted

SECTION FOUR RCOMMENDATIONS

This section provides mitigation alternatives pertaining to the rockfall-prone slopes, shoulder stabilization, cut slopes, roadway subexcavation and soil corrosion potential.

4.1 ROCKFALL MITIGATION ALTERNATIVES

The following four alternatives can be considered to mitigate rockfall along the route:

1. Alignment shifts to provide the maximum allowable distance from the rockfall source slope to the edge of the traveled way.

2. Engineered rockfall ditch to increase the percent of retained rockfall thereby decreasing the likelihood of fallen rock will reaching the traveled way.

3. Slope scaling to remove the loose rock that presents a hazard as a future potential rockfall.

4. Minor slope rounding at the crest or brow of over steepened slopes to alleviate the additional potential of rockfall by flattening the top of the existing cut.

The most practical recommended alternative is a combination of three or all of the aforementioned items on any given slope and/or adjacent roadway elements. Coupling the alternatives of crest rounding, ditch improvements, and slope scaling, which utilizes the same equipment and crews, may greatly reduce rockfall frequency. As there is a direct relationship between roadway alignment and available ditch width these two mitigation alternatives will be discussed simultaneously. This report will address slope scaling and slope rounding individually.

As discussed in Section 3, unconsolidated slopes were selected to receive rockfall mitigation as they are the main source of rockfall that can be mitigated within the scope and budget of this project. The selection of specific unconsolidated slopes for rockfall mitigation was based on several factors including, but not limited to:

Input from Inyo County on frequently maintained rockfall areas. Meaning, where the county has frequent issues clearing the roadway of fallen rocks or where ditches must be cleared of fallen rock often.

Existing roadway condition. Often areas susceptible to rockfall can be determined by the condition of adjacent roadway features. Along the route rockfall impacts have resulted in divots and damage to the existing pavement surface.

Experience with similar slopes with rockfall potential hazard and the associated risk.

Table 4 presents the four selected slopes and their recommended rockfall mitigation alternatives.

Table 4: Recommended Rockfall Mitigation Alternatives

Station to Station

Rockfall Mitigation Alternative

1) Roadway

Realignment

2) Engineered Rockfall

Ditch

3) Slope Scaling 4) Slope Rounding

132+50 - 133+50 -- X X X

136+00 - 136+25 -- X X X

155+00 - 158+50 X X X --

168+00 - 174+00 X X X X

Alignment shifts from Station 132+50 to 136+25 were not pursued at the request of the partner agency as realignment at these locations would eliminate campground parking on the outboard roadway shoulder. Shifting the roadway and eliminating parking areas could invite parking below the rockfall-prone slope.

Slope rounding denoted in the above table is anticipated to be minimal and should be performed as part of the scaling operation. Feasibility of the slope rounding should be evaluated during the pre-scaling meeting.

4.2 ROADWAY REALIGNMENT AND ROCKFALL CATCHMENT DITCHES

4.2.1 ALIGNMENT SHIFTS

At all rockfall locations the ditch widths are limited to non-existent, resulting in rockfall reaching the paved surface. To increase ditch width and thereby rockfall catchment capacity; two measures can be implemented. The first is performing cut slope excavation to move the slope further from the roadway, or shifting the roadway further from the existing cutslope.

Excavation of the unconsolidated slopes to produce sufficient ditch width in addition to laying the slope back to a lesser angle to reduce long-term rockfall is not considered feasible or within the original scope of the project because it would require a vast amount of material be excavated and moved off-site. Fortunately, at many rockfall locations it is feasible to shift the roadway away from the cutslope to create the maximum possible inboard ditch catchment area without requiring an outboard retaining structure for additional roadway bench width.

4.2.2 ENGINEERED CATCHMENT DITCHES

Engineered catchment ditches are recommended at all rockfall locations to provide effective measures for controlling the amount of rock falling onto the roadway. State-of-the-practice catchment ditch design currently follows the guidance provided in the 2001 Oregon Dept. of

Transportation (ODOT) manual, entitled “Rockfall Catchment Area Design Guide” (RCAD). In the ODOT study, over 11,000 rocks ranging 1-3 ft in diameter, were rolled from slopes of various heights and slope ratios to catchment ditches of varying width and inclinations of

1V:4H, 1V:6H and Flat (0V:1H) to determine rockfall retention percentages. Figure 3 below displays the geometry conditions used in the RCAD rockfall criteria. The 1V:4H foreslope ratio proved to be the most effective foreslope configuration tested to retain rockfall and was the ratio used in percent retained analysis in the following discussion.

Figure 3: General slope geometry used in the RCAD analysis

Traditionally the RCAD is used to achieve a targeted percentage of retained rockfall. For example if an objective to catch 50 percent of the rockfall originating from the top of a 70 foot high, 53 degree cutslope was set then according to design criteria presented in the RCAD manual a 13-foot wide ditch with a 1V:4H foreslope must be constructed (RCAD Figure 5.19).

Constructing a 13-foot catchment ditch along the route in many cases would dictate that the alignment be shifted so far to the outboard side that a retaining structure must be constructed to acquire the necessary bench width. However, given the scope of the project it was not feasible to assign a desired percent catchment to each existing cutslope and design the alignment around that, but rather provide the maximum possible percent retained by maximizing the ditch width coupled with a 1V:4H foreslope while remaining on the existing roadway bench. Quantification in the percent retained of the existing conditions verses the proposed percent retained was performed to verify the added improvements in alignment shifts and engineered catchment ditches were improving the rockfall catchment at the rockfall prone slopes. A summary of this data is presented in Table 5 below. The full set of measurements and data used in this comparison is presented in Appendix D.

Varies

Average 3.6 ft to 8 ft feet

Varies 40 ft to 80 ft

Slope Angle Varies 1V:1H to 1V:0.5H

Table 5: Summary of Existing Percent Rockfall Containment to Proposed Percent Rockfall Containment

Station to Station

Slope Geometry Existing Alignment Proposed Alignment

Improvement

In Percent

Containment

Maximum

Slope

Angle

Maximum

Height Of

Potential

Rockfall

Average

Ditch

Width

(ft)

Foreslope

Estimated

Percent

Containment

Average

Ditch

Width

(ft)

Foreslope

Estimated

Percent

Containment

132+00 - 137+00 1V:1H 50 3.6 Flat 6% 3.6 1V:4H 23% 17%

148+00 - 150+00 1V:1H 40 4.2 Flat 2% 5.6 1V:4H 43% 41%

150+00 - 159+50 1V:0.5H 80 5.8 Flat 8% 8.0 1V:4H 34% 27%

167+00 - 175+00 1V:0.5H 50 6.6 Flat 13% 6.9 1V:4H 45% 32%

The ODOT design guidance provides a good index for catchment ditch design and expected performance. However, factors such as rock shape and density, slope roughness, slope hardness, and slope profile configuration (e.g., linear, benched) will also affect ditch catchment performance.

Figure 4: Photograph showing typical existing ditch conditions. Removing debris and duff and reestablishing all ditches along the route will improve the overall rockfall catchment.

It is recommended to reestablish ditch widths, depths and profiles wherever possible and that an item be added to the contract to cover all the ditch rehabilitation throughout the Whitney Portal

Road. This will improve the retention of minor rockfall-prone areas with minimal required effort.

Performing regular maintenance of the ditches after construction will also provide some degree of effective rockfall mitigation for all the cut slopes along the roadway.

4.3 SLOPE SCALING

Slope scaling is the removal of loose, broken, or partially detached rock from the slope using manual methods, or excavation equipment. Manual, or “hand-scaling”, methods commonly involve 3 man crews consisting of experienced scalers skilled at systematically removing loose, isolated rockfall hazards with a variety of specialized hand tools, manual and pneumatic jacks.

Scaling crews typically work off ropes, but may occasionally work from crane baskets or lifts, and always require spotters on the roadway to continually survey the slope for unsafe working conditions. Slope excavation, or “machine-scaling”, methods commonly involve excavators using buckets to pry rock from the slope, hydraulic hammers to bring down larger unstable rock masses, and/or heavy chains to brush large quantities of loose debris from the slope. Machine scaling uses similar crew sizes and clean-up/haul equipment as hand-scaling, and also relies on roadway spotters to ensure operation safety. Hand-scaling and machine-scaling may be done in tandem on raveling slopes where high, localized rockfall exists outside the reach of common excavators (30-40 ft). For high slopes with substantial rockfall hazard, long-reach excavators are available that extend to well over 70 ft.

As previously stated four locations have been identified for rockfall scaling treatment. Table 6 specifically addresses the estimated crew hours and volume of material the scaling operation will produce within each station range. The table also provides an approximate location where the scaling will be performed on each slope and the anticipated effort (“Light” to “Heavy”) of scaling the operation. Appendix C photographically depicts the areas of scaling interest or specific rocks that the scaling operation should address. The highlighted areas may be adjusted as they are general locations of the proposed scaling operation. All proposed scaling locations should be discussed on-site during the scaling pre-work meeting with a member of the CFLHD

Geotechnical team.

It is recommended that the scaling operation be accomplished by means of hand tools only.

Unless the contractor can successfully demonstrate the use of machinery (long-reach excavators) to the satisfaction of the CFLHD Geotechnical engineer, scaling should not incorporate machinery as their use could easily loosen additional rock within the colluvial slopes that was not intended to be removed. Equipment used during the scaling operation and ditch clean-up work should be sufficiently armored for the operator’s safety. As with any construction operation, it is the contractor’s responsibility to independently access the safety of the scaling operation and provide necessary measures to protect all construction personal, traveling public and roadway elements from harm.

Table 6: Estimated Scaling Effort and Quantity

Station to Station Crew Hours Estimated Scaling Volume (CUYD)

Anticipated Scaling Effort & Particular Location On Each Slope (2)

For info only

132+50 - 133+50 8 40 Heavy scaling at slope brow approximately 40-50 vertical feet on the slope.

136+00 - 136+25 4 20 Heavy scaling at slope brow approximately 20-30 vertical feet on the slope.

155+00 - 156+50

12 60

Light scaling at slope brow approximately 70-90 vertical feet on the slope and intermittent boulders on slope.

156+50 - 158+50 Heavy scaling at slope brow approximately 70-90 vertical feet on the slope and intermittent boulders on slope.

168+00 - 169+00

12 60

Heavy scaling at slope brow approximately 40-50 vertical feet on the slope.

169+00 - 170+00 Light scaling at slope brow approximately 40-50 vertical feet on the slope.

170+00 - 171+50 Heavy scaling at slope brow approximately 40-50 feet vertical feet on the slope and intermittent boulders on slope.

171+50 - 174+00 Light scaling at slope brow approximately 40-50 vertical feet on the slope.

Notes:

(1): Stations, quantities and measurements presented are approximate and may be adjusted during the pre-scaling meeting and/or during scaling operations after mutual agreements between the contractor and the FHWA.

(2): Vertical distance is measured from top of existing pavement on the in-board ditch side and projected onto slope. Slope distance is not presented in the above table but will be greater than vertical distance.

Assumptions of the slope scaling recommendations include:

For slopes with moderate to low volumes of loose rock, scaling crews can quickly dress slopes with minimal delays to traffic. For slopes with large rockfall volumes, large localized rock masses to be removed, dangerous rockfall exposures high on the slope, or requiring slope crest excavation, roadway closures may be required.

Scaling cannot be expected to remove the entire loose rock hazard from the slope. Hand-scalers will generally do a better job of removing small, loose rock to ensure safe overhead conditions as work progresses downslope. Machine-scaling operations typically remove larger volumes of larger rock from the slope, but tend to leave small slope debris behind.

“Chaining” or “brushing” by dragging chains over the slope can be effective in removing small rock debris.

Hand scaling should not progress downslope if stable conditions cannot be obtained within the upper reaches of the slope. If unstable conditions cannot be remedied, the scaling operation should be abandoned or machine scaled after discussions with a member of the

CFLHD Geotechnical staff.

Scaling results are proportional to the skill and experience of the scalers. Experienced crews cost more, but typically work faster and produce higher quality results (buying years of slope performance in many cases).

Unsupervised scaling may result in substantial over-excavation and significant overruns in scaling quantities if expected results are not well communicated and closely monitored.

Scaling is not a permanent solution to rockfall. Scaling frequency is dependent on many factors, including the erosional/weathering durability of the slope, extent and persistence of structural features producing loose rock, and presence of other effective mitigation measures such as catchment ditches or barriers.

Effective scaling programs require clearly communicated expectations during contracting (pre-bid on-site meetings and special contact specifications), and supervised operations by knowledgeable construction management staff. Scaling measures for each slope identified should be evaluated early in the scaling program for continuity of work products.

4.3.1 SLOPE ROUNDING

Although it is not recommended to perform any large-scale cut slope excavations to alleviate rockfall potential, smaller excavations to round the slope at the slope’s brow or crest can be performed just prior to rock scaling operations. Slope rounding involves flattening or rounding of the upper reaches of the cut. Top-of-cut areas are commonly comprised of surficial soils and often a vegetated profile creating near-vertical scarps. These areas retain rock within the scarp that can be easily released with added moisture or loss of the vegetated cover. Removing these scarps to create a rounded profile will reduce the risk of a high-potential energy rock being released with greater chance of making it to the roadway surface. Once the slope has been rounded it is recommended that these areas are seeded and if required covered with erosion control matting. If possible the removal of furrows and rivulets should be performed at the top of the cuts/ rounding locations to promote sheet flows over the slope rather than concentrated flows.

4.4 SHOULDER STABILIZATION

Two shoulder embankment stabilization methods were developed to repair and protect the roadway embankment lost from surface drainage erosion.

Stabilization Method 1- Constructed of mechanically placed boulders according to Section 252 of the SCR’s and 705.04(a) of the FP-03. The rock should be placed to match the surrounding slopes but should not exceed a 1V:1.5H slope face. The rock should bench into the slope with vertical steps not to exceed 4 feet and minimum bench widths of 4 feet to 8 feet, depending on the height of the proposed repair.

Stabilization Method 2 – Used when a slope steeper than a 1V:1.5H is needed to match existing topography. Use mechanically placed boulders in concrete or grout according to Section 252 of the SCR’s and 705.04(a) of the FP-03. Place rock at a maximum slope face of 2V:1H and 4-foot maximum height, including a minimum foot of embedment and minimum footing width of 4 feet. To ensure long-term stability of the rock face, at least 15% of the voids within the placed rock mass must be filled with concrete or grout.

4.5 CUT SLOPE RECOMMENDATIONS

In general, the maximum recommended slope ratios for proposed cut slopes vary between

1V:1.5H to 1V:3H for the cut slopes constructed in soil or colluvial slopes (block in matrix). The recommended slope ratio is dependent on the nature of the observed material and the existing stability of the slope. During the excavation of cut slopes on the project large boulders up to 5 feet (or larger) should be expected within the proposed excavation limits. Care should be taken to avoid over excavation by removing (or destabilizing) large boulders found to be crossing the proposed finished slope “neat line”.

The cut slope ratio of 1V:1.35H from station 619+40 to 620+00 is intended to retreat the top of the proposed cut at least 4 to 5 feet away from the power pole elements on the bench above the slope, specifically a boulder to which a power pole’s guy wire is attached. If during construction survey and slope staking it is revealed that top of the cut will come within the 4 to 5 foot clear distance, the FHWA construction staff should be notified of the actual slope ratio required to meet the clear distance for evaluation of slope stability. A station-by-station recommended cutslope ratio is presented in Table 7. These recommendations are based off of the 30 percent design alignment.

A slope ratio of 1V:2H is recommended as the maximum slope ratio for proposed fill slopes.

Table 7: Recommended Cut Slope Ratios by Station

Station to Station Side Slope Type Maximum Recommended Cut Slope

Ratio (V:H)

279+00 - 335+00 LT & RT Boulders in Matrix- Predominantly Matrix 1:3

355+00 - 370+00 LT & RT

Boulders in Matrix Weathered Granite in lower half of slope

- Predominantly Matrix 1:2

561+50 - 563+00 RT Boulders in Matrix- Predominantly Boulders 1:1.5

617+00 - 619+40 LT Boulders in Matrix- Predominantly Boulders 1:1.5

619+40 - 620+00 LT Boulders in Matrix- Predominantly Boulders 1:1.35

624+50 - 626+50 LT Boulders in Matrix- Predominantly Boulders 1:1.5

640+00 - 641+00 RT Adversely Jointed Rock Outcrop DO NOT CUT

Notes:

(1) The cut transition at station 619+40 from a 1V:1.5H to a 1V:1.35H is intended to retreat the top-of-cut at least 5 feet from the base of the boulder containing the power pole guy wire anchor at approximate station 619+50.

4.6 SUBEXCAVATION

Subexcavation may be required in several areas along the roadway. These areas can be identified by wheel rutting and alligator cracking in the pavement surface. A minimum of 1 foot of standard subexcavation was identified for Station 245+00 to 247+00 left. This will entail excavation and re-compaction or complete replacement (at the discretion of the CO) of a minimum of 1 foot of material below the pavements structural section. The bottom of the excavation should be lined with separation geotextile. It is recommended that the contract provide a provisional subexcavation quantity (in addition the aforementioned station range) to be used at the CO’s discretion in event that additional subexcavation locations arise during construction.

4.7 CORROSION

Corrosion tests were conducted as part of the Pavements and Materials investigation. Refer to the Pavements and Materials Report Dated June 2014 (Report #14-02) detailing the recommendations for corrosion mitigation and supporting laboratory testing.

4.8 SHRINK/SWELL RECOMMENDATIONS

The proposed Whitney Portal will require cuts in slopes comprised of sands and gravels with cobbles and boulders. Many of the fill slopes are overlain with a veneer of loose, uncompacted granular side-cast material with cobbles and boulders up to several feet thick.

For the purpose of estimating shrink/swell values, sands and gravels with cobbles and boulders are assumed to be the predominate material located in permanent cuts and excavations for shoulder stabilization below the roadway. The recommended shrink/swell factors are based on a combination of standard tabled values for common materials in the FLH Technical Guidance

Manual (2006) and experience with other CFLHD projects in similar materials.

The estimated shrink/swell values for the sands and gravels with cobbles and boulders of the cut slopes are assumed to Shrink 5percent (Shrink Factor 0.95) if reused as embankment.

4.9 SPECIFICATIONS

Special provisions were developed to be consistent with geotechnical recommendations stated above and should be incorporated into the special contract requirements (SCR). The following

SCR’s were added for this project:

Section 252 – Special Rock Embankment

Section 623 – Special Labor Slope Scaling

4.10 LIMITATIONS

The recommendations in this report are based on the data obtained from visual investigations, field review, and laboratory test results. The results of these explorations and tests represent conditions at the specific locations indicated. Subsurface variations across the site are likely and may not become evident until excavation is performed. The Analysis and Recommendations sections in this report include interpretations and recommendations developed by the

Government in the process of preparing the design. These interpretations are not intended as a substitute for the personal investigation, independent interpretation, and judgment of the

Contractor.

SECTION FIVE -- REFERENCES

American Association of State Highway and Transportation Officials (AASHTO), 2012, LRFD

Bridge Design Specifications, 6th Edition.

Beanland, S., and Clark, M., “The Owens Valley Fault Zone, Eastern California, and Surface

Faulting Associated with the 1872 Earthquake”, U.S. Geological Survey Bulletin, Denver, 1982

Federal Lands Highway (FLH), Project Development and Design Manual (PDDM), FHWA, 2008, dated March.

Federal Lands Highways (FLH), 2006, Technical Guidance Manual (TGM), A geotechnical supplement to the FLH Project Development and Design Manual.

Pierson, L.A., C.F. Gullixson, and R.G. Chassie, 2001, Rockfall Catchment Area Design Guide –

Final Report, Oregon Dept. of Transportation Research Group pub. No. SPR-3(032), November 2001, pp.92.

United States Geological Survey (USGS) 2008 National Seismic Hazard Maps http://geohazards.usgs.gov/cfusion/hazfaults_search/hf_search_main.cfm

APPENDIX A

FIGURES

FIGURE 1- PROJECT LOCATION AND SITE MAP

FIGURE 2- GEOLOGIC MAP OF THE WHITNEY PORTAL ROAD PROJECT AND SURROUNDING

REGION

FIGURE 2.1- DESCRIPTION OF GEOLOGIC UNITS

Dominic.Monarco Callout Station 279+00 End Segment 1 Start Segment 2

Dominic.Monarco Callout Station 373+00 End Segment 2 Start Segment 3

Dominic.Monarco Text Box Begin Segment 1

Dominic.Monarco Text Box End Segment 3

Dominic.Monarco Text Box

FIGURE 1- PROJECT LOCATION AND SITE MAP

Figure 2- Geologic Map of the Whitney Portal Road Project and Surrounding Region.

Dominic.Monarco Callout Whitney Portal Road

Dominic.Monarco Text Box Approximate Scaling Locations

Dominic.Monarco Line

Dominic.Monarco Line

Dominic.Monarco Line

Dominic.Monarco Callout U.S. Hwy 395

Dominic.Monarco Callout Faults belonging to the Sierra Nevada Frontal Fault Zone

Dominic.Monarco Callout Faults belonging to the Owens Valley Fault Zone

Dominic.Monarco Line

Dominic.Monarco Line

Dominic.Monarco Text Box Lone Pine, CA

Line

Figure 2.1- Description of Geologic Units

APPENDIX B

LABORATORY TESTING

APPENDIX B

LABORATORY TEST RESULTS

B.1 INTRODUCTION

Laboratory tests were completed on select soil samples recovered for the field exploration program in general accordance with the American Association of State Highway and

Transportation Officials (AASHTO) and American Society for Testing and Materials (ASTM) testing methods. The laboratory testing program was completed to provide data for engineering studies and to classify the materials into similar geologic groups. The testing program included soil physical properties. Individual test results are summarized in Table B-1, and gradation plots of samples from each location are presented in Figures B1 and B2.

The following sections describe the laboratory testing procedures.

B.2 SOIL PHYSICAL PROPERTIES TESTS

Physical properties testing included soil identification by visual and manual means, and tests to determine grain size distribution, fines content, and Atterberg limits. When sufficient laboratory testing was completed, select samples from borings were classified using the Unified Soil

Classification System (USCS) and American Association of State Highway and Transportation

Officials (AASHTO) soil classification system. Both the visual soil identification system and the referenced soil classification systems are summarized in the Soil Classification Field Reference in Appendix A. Test results are presented in the attached laboratory reports.

The following sections describe the individual physical properties test procedures.

Gradation

The grain size distribution of selected samples was determined in general accordance with the

AASHTO T 311 and ASTM D 1140. These tests aid in the classification of soils and provide correlating data with engineering properties of soils, such as permeability, strength, swelling potential, and susceptibility to frost action.

Atterberg Limits

Liquid and plastic limit tests were performed on selected fine-grained samples. The tests were completed in general accordance with AASHTO T 89 and T 90 (ASTM D 4318). The Atterberg limits include liquid limit (LL), plastic limit (PL), and plasticity index (PI), which is the plastic limit subtracted from the liquid limit. These limits are generally used to assist in classification of soils, to indicate soil consistency, and to provide correlation to engineering properties.

Table B-1: Summary of Laboratory Test Results

Station Field

Number

Offset from

CL (ft)

Depth

Interval

(ft)

Grain Size Distribution (%)

L iq u id

L im it

P la st ic it y I n d ex

Soil Classification

F ig u re

N o

G ra v el

S an d

F in es

USCS AASHTO

353+50 353+50 40 0 - 1 11 78 11 NP NP SP-SM A-2-4 (0) B1

366+50 366+50 40 0 - 1 5 76 19 NP NP SM A-2-4 (0) B2

0 0 5 6 5 22 51 11 mm

75.0

37.5 PL= NP LL= NP PI= NP

25.0

19.0

12.5 USCS (D 2487)= SP-SM AASHTO (M 145)= A-2-4 (0)

9.5

4.75

2.00 D10= D30= D60= Cu= Cc=

1.18

0.43

0.15 The sample is from the top of an existing cut.

0.08

PROJECT NUMBER: CA FLAP CRS 4018(1) Reported by: Darrell Harding

PROJECT NAME: Whitney Portal Road Title: CFL Laboratory Manager

PROJECT LOCATION: Inyo National Forest, Inyo County, California Date Tested:

STATION: 353+50, 40 feet from centerline

HOLE NUMBER: -

FIELD NUMBER: 353+50 FIGURE: B1

SAMPLE DEPTH: 0-1 foot

TEST RESULTS

Opening

Size

Percent

Finer

Material Description

Poorly Graded Sand with Silt inches %

3 Atterberg Limits (ASTM D 4318)

1-1/2 100

1 95

3/4 95 Classification

1/2 93

3/8 92

#4 89 Coefficients

#10 84 ~0.07 0.16 0.4 ~5.7 ~0.9

#16 80

#40 62 Remarks

#100 28

#200 11

5/20/2014

0.0010.010.11101001000

P E

R C

E N

T R

E T

A

IN

E D

B

Y W

E

IG

H T

P E

R C

E N

T P

A S

S

IN

G

B Y

W E

IG

H

T

GRAIN SIZE IN MILLIMETERS

PARTICLE SIZE DISTRIBUTION REPORT

SIEVE ANALYSIS HYDROMETER ANALYSIS

BOULDERS COBBLES

% GRAVEL

COARSE FINE

% SAND

COARSE MEDIUM FINE

% FINES

36" 24" 12" 6" 3" 1 1/2" 3/4" 3/8" #4 #16#8 #30#10 #40 #50 #100 #200

915 610 305 152 75 37.5 19 9.5 4.75 2.36 2 1.18 .6 .425 .3 .15 .075 .037 .019 .009 .005 .002 .001

1 MIN 4 MIN 19 MIN 60 MIN

7 HR-

15 MIN

25 HR-

45 MIN

TIME READINGSSIZE IN INCHES

U.S. STANDARD SIEVE

OPENING IN INCHES

U.S. STANDARD SIEVE

NUMBERS

1"

12.5

1/2"

SILT CLAY

% +3"

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

CENTRAL FEDERAL LANDS HIGHWAY DIVISION

0 0 0 5 5 21 50 19 mm

75.0

37.5 PL= NP LL= NP PI= NP

25.0

19.0

12.5 USCS (D 2487)= SM AASHTO (M 145)= A-2-4 (0)

9.5

4.75

2.00 D10= D30= D60= Cu= Cc=

1.18

0.43

0.15 The sample is from the top of an existing cut.

0.08

PROJECT NUMBER: CA FLAP CRS 4018(1) Reported by: Darrell Harding

PROJECT NAME: Whitney Portal Road Title: CFL Laboratory Manager

PROJECT LOCATION: Inyo National Forest, Inyo County, California Date Tested:

STATION: 366+50, 40 feet from centerline

HOLE NUMBER: -

FIELD NUMBER: 366+50 FIGURE: B2

SAMPLE DEPTH: 0-1 foot

#100 33

#200 19

5/20/2014

~11 ~4.5

#16 87

#40 69 Remarks

3/8 99

#4 95 Coefficients

#10 90 ~0.02 0.14 0.22

3/4 100 Classification

1/2 99 inches %

3 Atterberg Limits (ASTM D 4318)

1-1/2

TEST RESULTS

Opening

Size

Percent

Finer

Material Description

Silty Sand

0.0010.010.11101001000

P E

R C

E N

T R

E T

A

IN

E D

B

Y W

E

IG

H T

P E

R C

E N

T P

A S

S

IN

G

B Y

W E

IG

H

T

GRAIN SIZE IN MILLIMETERS

PARTICLE SIZE DISTRIBUTION REPORT

SIEVE ANALYSIS HYDROMETER ANALYSIS

BOULDERS COBBLES

% GRAVEL

COARSE FINE

% SAND

COARSE MEDIUM FINE

% FINES

36" 24" 12" 6" 3" 1 1/2" 3/4" 3/8" #4 #16#8 #30#10 #40 #50 #100 #200

915 610 305 152 75 37.5 19 9.5 4.75 2.36 2 1.18 .6 .425 .3 .15 .075 .037 .019 .009 .005 .002 .001

1 MIN 4 MIN 19 MIN 60 MIN

7 HR-

15 MIN

25 HR-

45 MIN

TIME READINGSSIZE IN INCHES

U.S. STANDARD SIEVE

OPENING IN INCHES

U.S. STANDARD SIEVE

NUMBERS

1"

12.5

1/2"

SILT CLAY

% +3"

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

CENTRAL FEDERAL LANDS HIGHWAY DIVISION

APPENDIX C

SLOPE SCALING

FIGURE C1- STATION 132+50 to 133+50

FIGURE C2- STATION 136+00 to 136+25

FIGURE C3- STATION 155+00 to 156+50

FIGURE C4- STATION 156+50 to 158+50

FIGURE C5- STATION 168+00 to 174+00

Polygon

Dominic.Monarco Text Box FIGURE C1- STATION 132+50 to 133+50

Dominic.Monarco Text Box

(1) Scaling locations may be adjusted after pre-scaling meeting.

Dominic.Monarco Text Box Areas of Scaling interest (1)

Dominic.Monarco Polygon

Dominic.Monarco Polygon

Dominic.Monarco Polygon

FIGURE C2- STATION 136+00 to 136+25

Dominic.Monarco Text Box

(1) Scaling locations may be adjusted after pre-scaling meeting.

Dominic.Monarco Text Box Areas of Scaling interest (1)

Dominic.Monarco Polygon

Dominic.Monarco Polygon

FIGURE C3- STATION 155+00 to 156+50

Dominic.Monarco Polygon

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Text Box Areas of Scaling interest (1)

Dominic.Monarco Polygon

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Sticky Note Unmarked set by Dominic.Monarco

Dominic.Monarco Text Box

(1) Scaling locations may be adjusted after pre-scaling meeting.

Oval

FIGURE C4- STATION 156+50 to 158+50

Dominic.Monarco Text Box

(1) Scaling locations may be adjusted after pre-scaling meeting.

Dominic.Monarco Text Box Areas of Scaling interest (1)

Dominic.Monarco Polygon

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Oval

Dominic.Monarco Polygon

(1) Scaling locations may be adjusted after pre-scaling meeting.

(2) Remove tree debris at center of photograph

Dominic.Monarco Oval

Dominic.Monarco Polygon

Dominic.Monarco Text Box FIGURE C5- STATION 168+00 to 174+00

Dominic.Monarco Text Box Areas of Scaling interest (1)

Dominic.Monarco Oval

Dominic.Monarco Polygon

Dominic.Monarco Polygon

Dominic.Monarco Polygon

Dominic.Monarco Polygon

APPENDIX D

ROCKFALL AREA CATCHMENT DATA

Max Height of Potential

Rockfall Slope W

(ft)

Catchment Area Slope

(RCAD

Designation)

Est % Catchment

W (ft)

Catchment Area Slope

(RCAD

Designation)

Est % Catchment

132+00…