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California bearing ratio

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The California Bearing Ratio ( CBR ) is a measure of the strength of the subgrade of a road or other paved area, and of the materials used in its construction.

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41-567: The ratio is measured using a standardized penetration test first developed by the California Division of Highways for highway engineering . Empirical tests measure the strength of the material and are not a true representation of the resilient modulus . The CBR is the ratio of the bearing load that penetrates a material to a specific depth compared with the load giving the same penetration into crushed stone . The test measures neither Stiffness Modulus nor Shear Strength directly, but gives

82-552: A Task Force Committee on Transportation to study the state transportation system and recommend major reforms. One of the proposals of the task force was the creation of a State Transportation Board as a permanent advisory board on state transportation policy; the board would later merge into the California Transportation Commission in 1978. In September 1971, the State Transportation Board proposed

123-756: A combined measure of both. Penetration is measured by applying the bearing load on the sample using a standard plunger of diameter 50 mm at the rate of 1.25 mm/min. The CBR is expressed as a percentage of the actual load causing the penetrations of 2.5 mm or 5.0 mm to the standard loads on crushed stone. A load penetration curve is drawn. The load values on standard crushed stones are 1,370 kgf (13.44 kN) and 2,055 kgf (20.15 kN) at 2.5 mm and 5.0 mm penetrations respectively. The CBR can be mathematically expressed as: C B R = p p s ⋅ 100 % {\displaystyle CBR={\frac {p}{p_{s}}}\cdot 100\%} The CBR test

164-407: A mould of 150 mm diameter with a base plate and a collar, a loading frame and dial gauges for measuring the penetration values and the expansion on soaking. If a soaked (wet) measurement is desired, the specimen in the mould is soaked in water for four days and the swelling and water absorption values are noted. The surcharge weight is placed on the top of the specimen in the mould and the assembly

205-513: A new mission statement: "Provide a safe, sustainable, integrated and efficient transportation system to enhance California's economy and livability." The earliest predecessor of Caltrans was the Bureau of Highways, which was created by the California Legislature and signed into law by Governor James Budd in 1895. This agency consisted of three commissioners who were charged with analyzing

246-469: A reduction in service from ten trainsets operating 27 daily trains to seven trainsets operating 20 daily trains. Trainsets used for regular service are composed from a fleet of 52 bi-level Surfliner coaches (39 owned by Amtrak and 13 by Caltrans ), plus nine leased Amtrak Superliner long-distance coaches modified for push-pull operation. These Superliners are called flex cars, as they can be used for additional business class or coach seating, depending on

287-650: Is 79 to 90 miles per hour (127 to 145 km/h). Much of the Pacific Surfliner ' s scenic route follows the Pacific coast , with the tracks being less than 100 feet (30 m) from the ocean in some locations. However, trains travel inland through expansive farmlands in Ventura County and industrial areas in the Los Angeles Basin , San Fernando Valley , and parts of Orange County . As of October 2023 ,

328-440: Is a penetration test in which a standard piston, with a diameter of 50 mm (1.969 in), is used to penetrate the soil at a standard rate of 1.25 mm/minute. Although the force increases with the depth of penetration, in most cases, it does not increase as quickly as it does for the standard crushed rock, so the ratio decreases. In some cases, the ratio at 5 mm may be greater than that at 2.5 mm. If this occurs,

369-737: Is an executive department of the U.S. state of California . The department is part of the cabinet -level California State Transportation Agency (CalSTA). Caltrans is headquartered in Sacramento . Caltrans manages the state's highway system , which includes the California Freeway and Expressway System , supports public transportation systems throughout the state and provides funding and oversight for three state-supported Amtrak intercity rail routes ( Capitol Corridor , Pacific Surfliner and San Joaquins ) which are collectively branded as Amtrak California . In 2015, Caltrans released

410-488: Is covered by District 3. Pacific Surfliner [REDACTED] All stations are accessible The Pacific Surfliner is a 350-mile (560 km) passenger train service serving the communities on the coast of Southern California between San Diego and San Luis Obispo . The Pacific Surfliner is Amtrak's third-busiest service (exceeded in ridership only by the Northeast Regional and Acela ), and

451-497: Is placed under the plunger of the loading frame. CBR values for common soil subgrades can be estimated according to the USC soil types, for example: clay around 2%, sand from 7% (poorly graded) to 10% (well graded), well graded sandy gravel 15%, clayey sand 5-20%, silty gravel 20-60%, gravel from 30-60% poorly-graded to 40-80% if well-graded. California Division of Highways The California Department of Transportation ( Caltrans )

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492-652: The Federal-Aid Highway Act of 1956 for the construction of its portion of the Interstate Highway System . Over the next two decades after Collier-Burns, the state "embarked on a massive highway construction program" in which nearly all of the now-extant state highway system was either constructed or upgraded. In hindsight, the period from 1940 to 1969 can be characterized as the "Golden Age" of California's state highway construction program. The history of Caltrans and its predecessor agencies during

533-745: The National Environmental Policy Act and the California Environmental Quality Act forced Caltrans to devote significant time, money, people, and other resources to confronting issues such as "air and water quality, hazardous waste, archaeology, historic preservation, and noise abatement." The devastating 1971 San Fernando earthquake compelled the agency to recognize that its existing design standards had not adequately accounted for earthquake stress and that numerous existing structures needed expensive seismic retrofitting . Maintenance and construction costs grew at twice

574-523: The Pacific Surfliner operates ten daily round trips between Los Angeles and San Diego. Five round trips continue north of Los Angeles: two run all the way to San Luis Obispo , and three run to Goleta (near Santa Barbara), with Amtrak Thruway motorcoach service over the rest of the route to San Luis Obispo. Thruway motorcoach connections are also available to San Pedro ; to Palm Springs and Indio ; and to San Jose or Oakland (with connections to Capitol Corridor trains) via Paso Robles . Because

615-418: The "Rail 2 Rail" reciprocal pass program with Coaster , while Laguna Niguel/Mission Viejo and Orange were served under a similar program with Metrolink . Ridership on the Pacific Surfliner peaked in fiscal year 2017, when it served nearly 3 million passengers. The Pacific Surfliner uses push-pull trainsets with a diesel locomotive at one end and a cab car at the other. The COVID-19 pandemic saw

656-403: The 1970s, as its institutional focus shifted from highway construction to highway maintenance. The agency was forced to contend with declining revenues, increasing construction and maintenance costs (especially the skyrocketing cost of maintaining the vast highway system built over the past three prior decades), widespread freeway revolts , and new environmental laws . In 1970, the enactment of

697-635: The 20th century was marked by many firsts. It was one of the first agencies in the United States to paint centerlines on highways statewide; the first to build a freeway west of the Mississippi River ; the first to build a four-level stack interchange ; the first to develop and deploy non-reflective raised pavement markers, better known as Botts' dots ; and one of the first to implement dedicated freeway-to-freeway connector ramps for high-occupancy vehicle lanes . In 1967, Governor Ronald Reagan formed

738-607: The Department of Engineering into the Department of Public Works, which continued to have a Division of Highways. That same year, three additional divisions (now districts) were created, in Stockton, Bishop, and San Bernardino. In 1933, the state legislature enacted an amendment to the State Highway Classification Act of 1927, which added over 6,700 miles of county roads to the state highway system. To help manage all

779-441: The Department of Transportation, of which the most important was the Department of Public Works and its Division of Highways. The California Department of Transportation began official operations on July 1, 1973. The new agency was organized into six divisions: Highways, Mass Transportation, Aeronautics, Transportation Planning, Legal, and Administrative Services. Caltrans went through a difficult period of transformation during

820-597: The F59PHI locomotives) are painted in a blue and silver livery that is unique to the Pacific Surfliner . Additional Amtrak-owned cars are added (up to 12-car consists) during periods of high demand, including San Diego Comic-Con , the San Diego County Fair , events at the Del Mar Racetrack , and after the 2018 Southern California mudflows closed Highway 101 . For 150 mph (241 km/h) or more in

861-450: The State of California into 12 districts, supervised by district offices. Most districts cover multiple counties ; District 12 ( Orange County ) is the only district with one county. The largest districts by population are District 4 ( San Francisco Bay Area ) and District 7 ( Los Angeles and Ventura counties). Like many state agencies, Caltrans maintains its headquarters in Sacramento , which

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902-755: The additional work created by this massive expansion, an eleventh district office was founded that year in San Diego. The enactment of the Collier–Burns Highway Act of 1947 after "a lengthy and bitter legislative battle" was a watershed moment in Caltrans history. The act "placed California highway's program on a sound financial basis" by doubling vehicle registration fees and raising gasoline and diesel fuel taxes from 3 cents to 4.5 cents per gallon. All these taxes were again raised further in 1953 and 1963. The state also obtained extensive federal funding from

943-600: The busiest outside the Northeast Corridor . Like all regional trains in California, the Pacific Surfliner is operated by a joint powers authority . The LOSSAN Rail Corridor Agency is governed by a board that includes eleven elected representatives from the six counties the train travels through. LOSSAN contracts with the Orange County Transportation Authority to provide day-to-day management of

984-448: The commissioners submitted their report to the governor on November 25, 1896, the legislature replaced the Bureau with the Department of Highways. Due to the state's weak fiscal condition and corrupt politics, little progress was made until 1907, when the legislature replaced the Department of Highways with the Department of Engineering, within which there was a Division of Highways. California voters approved an $ 18 million bond issue for

1025-481: The construction of a state highway system in 1910, and the first California Highway Commission was convened in 1911. On August 7, 1912, the department broke ground on its first construction project, the section of El Camino Real between South San Francisco and Burlingame , which later became part of California State Route 82 . The year 1912 also saw the founding of the Transportation Laboratory and

1066-464: The creation of a state department of transportation charged with responsibility "for performing and integrating transportation planning for all modes ." Governor Reagan mentioned this proposal in his 1972 State of the State address , and Assemblyman Wadie P. Deddeh introduced Assembly Bill 69 to that effect, which was duly passed by the state legislature and signed into law by Reagan later that same year. AB 69 merged three existing departments to create

1107-476: The creation of seven administrative divisions, which are the predecessors of the 12 district offices in use as of 2018 . The original seven division headquarters were located in: In 1913, the California State Legislature began requiring vehicle registration and allocated the resulting funds to support regular highway maintenance, which began the next year. In 1921, the state legislature turned

1148-570: The cross-ticketing arrangement with Coaster. A 13th daily round trip was added on October 14, 2019. On September 30, 2022, all rail service between Irvine and Oceanside was suspended due to coastal erosion under the track in San Clemente . Emergency repairs were expected to take at least 90 days. Full Pacific Surfliner service resumed on April 17, 2023. Service south of Irvine was again suspended on April 27 due to further erosion at Casa Romantica . Service resumed on May 27, 2023. Service

1189-600: The demand. A typical six-car set has a business class car; one Superliner car; two coach cars; a coach/café car with food sales on the lower level; and a coach/baggage/cab car equipped with coach seating, a checked baggage space on the lower level, and engineer's operating cab. LOSSAN has expressed interest in acquiring bi-level cars from a variety of sources, such as purchasing Surfliner and Superliner cars from Amtrak, as well as receiving bi-level cars from other Amtrak California services. The Surfliner cars were introduced in 2000–02, and were designed specifically to handle

1230-609: The demands of the nation's third-busiest rail line. They replaced the California Cars which had been introduced on the San Diegan in 1996, and had been fraught with problems in the latter part of the 1990s. A dedicated fleet of 16 Caltrans-owned Siemens Charger locomotives began entering service in late 2018. The Chargers replaced a fleet of 15 Amtrak-owned EMD F59PHI locomotives, which were sold to Metra in 2019. The Surfliner cars and Charger locomotives (and previously

1271-481: The inflation rate in this era of high inflation; the reluctance of one governor after another to raise fuel taxes in accordance with inflation meant that California ranked dead last in the United States in per capita transportation spending by 1983. During the 1980s and 1990s, Caltrans concentrated on "the upgrading, rehabilitation, and maintenance of the existing system," plus occasional gap closure and realignment projects. For administrative purposes, Caltrans divides

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1312-507: The local agencies administering the service rather than Caltrans. California Senate Bill No. 1225, passed in 2014, allowed LOSSAN to amend the joint powers agreement and become the sponsor of state-supported intercity passenger rail service in the corridor. In mid-2015, LOSSAN assumed oversight for the Surfliner. They are also working with Caltrans to assess rail operations from Los Angeles to San Diego to develop better connections, close gaps in

1353-525: The ratio at 5 mm should be used. The CBR is a measure of resistance of a material to penetration of a standard plunger under controlled density and moisture conditions. The test procedure should be strictly adhered to if a high degree of reproducibility is desired. The CBR test may be conducted on a remolded or undisturbed specimen in the laboratory. The test is simple and has been extensively investigated for field correlations of flexible pavement thickness requirement. The laboratory CBR apparatus consists of

1394-411: The roads of the state and making recommendations for their improvement. At the time, there was no state highway system, since roads were purely a local responsibility. California's roads consisted of crude dirt roads maintained by county governments, as well as some paved streets in certain cities, and this ad hoc system was no longer adequate for the needs of the state's rapidly growing population. After

1435-564: The schedule, and optimize the assets of the railroad. The route is the successor of the San Diegan , a Los Angeles –San Diego service operated since 1938 by the Santa Fe Railway . It had been one of the Santa Fe's premier routes until Amtrak took over operations in 1971. Initially there were three daily trips, but the schedule was expanded to six round trips during the 1970s with funding from

1476-639: The service and with contracts with Amtrak to operate the service and maintain the rolling stock (locomotives and passenger cars). The California Department of Transportation (Caltrans) provides the funding to operate the service and also owns all of the locomotives and some of the rolling stock; with Amtrak owning the rest. Portions of the line in southern Orange County have been suspended four times between 2022 and 2024 due to coastal erosion . The 350-mile (563 km) San Luis Obispo–San Diego trip takes approximately 8 hours, 52 minutes at an average speed of 38.9 miles per hour (63 km/h); maximum track speed

1517-576: The state of California. In 1988 the service was extended to Santa Barbara to provide the Central Coast with an additional train to Los Angeles, followed in 1995 with one trip a day going all the way to San Luis Obispo. To better reflect the route's extent, it was renamed the Pacific Surfliner in 2000. The route is named after the Surf Line , which now comprises the route's busiest section from Los Angeles to San Diego. A stop at Old Town Transit Center

1558-784: The station. The ongoing North Coast Corridor project plans to increase rail capacity on the route of the Surfliner in North San Diego County . Local agencies along with the host railroads formed the Los Angeles–San Diego-San Luis Obispo Rail Corridor Agency (LOSSAN) in 1989. The Pacific Surfliner is operated by Amtrak under the Amtrak California brand with funding provided by the California Department of Transportation (Caltrans). Serious discussions were held in 2009 regarding

1599-575: The stations at the ends of the line do not have wyes to turn equipment, trains are operated in push-pull mode. The locomotive is at the rear of the train, pushing the train from Goleta, San Luis Obispo or San Diego to Los Angeles. At Los Angeles, the train reverses at the station, and the locomotive pulls the train to San Diego or Goleta/San Luis Obispo, respectively. Run-through tracks are under construction at Union Station in Los Angeles to ease congestion and reduce time spent waiting to enter or depart

1640-451: Was added in 2004. Stops at Orange and Laguna Niguel/Mission Viejo were added in 2007 but dropped in 2012. On October 7, 2013, stops were added at Coaster stations at Carlsbad Village , Carlsbad Poinsettia , Encinitas and Sorrento Valley . The Carlsbad Poinsettia and Encinitas stops were dropped on October 9, 2017, due to low ridership. The Carlsbad Village and Sorrento Valley stops were dropped on October 8, 2018, due to changes with

1681-633: Was suspended again on June 5 due to continued erosion at Casa Romantica and resumed on July 19. Service was suspended on January 25, 2024, due to a landslide at San Clemente. The state declared an emergency on February 1, allowing the Orange County Transportation Authority to access emergency funding. Limited service through the landslide area resumed on March 6, 2024, followed by full service on March 25. The Pacific Surfliner runs on track owned by several private railroads and public agencies: Carlsbad Poinsettia , Carlsbad Village , Encinitas and Sorrento Valley stations were previously served under

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