Story highlights Authorities cite three people who try to enter the freeway 
 
 The feared traffic tie-ups do not materialize 
 
 A 10-mile section of Interstate 405 was closed for the weekend 
 
 A portion of a bridge came down as workers were demolishing another part of it 
 
 Southern California motorists honked their horns cheerfully as authorities reopened 10 miles of the nation's busiest highway ahead of schedule late Sunday night. 
 
 The latest phase in a massive project that led to the weekend closure of a large swath of Interstate 405 ended hours ahead of the Monday morning commute. 
 
 Southern California officials had dubbed the project "Carmageddon II." But the nightmare traffic tie-ups that prompted the fittingly Hollywood-worthy name did not materialize as motorists either stayed home or chose alternate routes. 
 
 California Highway Patrol said it cited three people who tried to enter the closed section of the freeway early Sunday. But overall, Los Angeles Mayor Antonio Villaraigosa declared the project a "resounding success." 
 
 "Our hope and expectation was that it would be Carmaheaven 2," Villaraigosa said, noting that a weekend-long highway shutdown last year had proceeded without a hitch, despite dire forecasts. "That hope and expectation came to be realized." 
 
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 The 405, as it's locally called, connects suburban San Fernando Valley with Los Angeles International Airport. It also stretches into the well-to-do neighborhoods of west Los Angeles, such as Bel Air and Brentwood. 
 
 The massive transportation project's main aim is to install what Villaraigosa said would be the "longest ... carpool lane in the nation" on the oft-packed highway. 
 
 The project did see an unscripted moment Saturday, when a section of the famed 50-year-old Mulholland Drive Bridge -- a fixture in the Los Angeles freeway-scape -- narrowly missed workers demolishing another part of it. 
 
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 Crews had planned to take down part of the bridge to make room for a wider roadway. The bridge will be reconstructed. 
 
 "On an operation of this size, of this magnitude, pieces come down of all different sizes and shapes," Dan Kulka of Kiewit Construction told CNN affiliate KABC. "We did not anticipate this, although it's not unusual for a big piece to come down like that." 
 
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 Governor signs law to make California home to nation's first truly high-speed rail ||||| Carmageddon Redux came to an end according to plan before Monday's commute got underway. But unlike last year's freeway closure, which wrapped up an unexpected 17 hours ahead of schedule, this time construction crews used most of their allotted time to make as many improvements to the 405 Freeway as possible, officials said. 
 
 While motorists opted for alternate routes, alternate modes of transportation or just stayed home, transportation officials deployed extra crews along the Sepulveda Pass to fill potholes, trim trees and pave three Southbound lanes — weeks of work squeezed into a two-day time frame. 
 
 Work crews also contended with a considerably bigger job. The northern span of the Mulholland Bridge over the 405 Freeway that was demolished this weekend was longer than the southern span knocked down last year, and the entire undertaking was more delicate because workers had to protect the newly built portion. 
 
 Photos: Carmageddon II 
 
 "This was the mother of all public works projects in Los Angeles," said Los Angeles County Supervisor Zev Yaroslavsky, whose district includes the Sepulveda Pass. "This has not been easy." 
 
 Workers began removing barriers to the northbound 405 onramps between the 10 and 101 freeways around 8:30 p.m. A slow-moving motorcade of CHP cruisers, lights flashing, led the first procession of vehicles on the newly reopened freeway. 
 
 Los Angeles Mayor Antonio Villaraigosa declared the weekend "a resounding success," speaking in English and Spanish at a press conference at "Camp Carmageddon" overlooking the nation's busiest freeway. It was not just that work crews kept on schedule despite 100-degree heat and other challenges, but that freeway-loving Southern Californians showed once again that they could handle the temporary blockage of a major artery without suffering a heart attack. 
 
 "People understood they needed to stay away from the area," Villaraigosa said. "They did what they needed to do to make sure it went as smoothly as it did." 
 
 The two-day closure of the 10-mile stretch of the 405 was part of a $1-billion, four-year project to expand the often-choked freeway with a northbound carpool lane. Most of the work requires only an occasional closure of a lane or two. But demolishing the 80-foot-high Mulholland Bridge to make room for the extra lane necessitated a complete closure. 
 
 This time, construction crews had to take apart a span that was nearly one-third bigger, said Mike Barbour, director of the 405 widening project for the Metropolitan Transportation Authority. 
 
 Crews struggled to demolish four concrete support structures — two more than last year — each encased with 3/4-inch steel to protect against earthquakes. In addition, the demolition proceeded more cautiously than last time to ensure that raining chunks of concrete and steel didn't damage the new bridge under construction. 
 
 "We knew it was going to take longer because there was 30% more bridge to demo," Barbour said. "We didn't care as much about getting it done ahead of schedule. We thought it was more important to finish as much work as we can this weekend to save future closures." 
 
 To that end, the California Department of Transportation deployed crews to conduct routine maintenance while the freeway lanes were free of cars. Villaraigosa said that decision saved $150,000. 
 
 Bonnie Spence, who lives near Sunset Boulevard and the 405, said she was happy the city was taking its time to get more work done. "Just keep going — you've already alerted everyone," she said as she took her dog for an evening walk. But she said she was mindful that the project was far from complete. 
 
 "This is going on for another year," she said. "People need to remember to be courteous to their fellow Angelenos." 
 
 By early afternoon Sunday, the last pieces of the Mulholland Bridge had been removed and crews began hauling away 2,700 cubic yards of material, including 300 tons of steel, and a four-foot-thick pad of dirt dumped on the roadway to protect it from falling debris. By nightfall, street sweepers were scouring the roadbed, and inspectors were looking for damage before giving final clearance for reopening. 
 
 The weekend freeway closure rippled through the community in surprising ways. Reports of crime dropped, as did air pollution, as people left their vehicles at home and set off on foot. 
 
 Most daredevils and free spirits resisted the temptation to exploit the empty freeway — apparently heeding the stern California Highway Patrol's warning of "zero tolerance" for pranksters. Authorities made no arrests, and by Sunday night had issued only seven citations: four to a group of inline skaters and three to pedestrians. Two of them were newlyweds hoping to extend their celebration under the pre-dawn harvest moon Sunday. 
 
 "Their wedding gift was a citation," CHP Officer Rick Quintero said. 
 
 Traffic flowed relatively smoothly throughout the Southland on Sunday as word of the closure saturated the airwaves and flashed in lights on electronic freeway alert signs as far away as the San Francisco Bay Area. 
 
 Heather Orsi and Elizabeth Wattiker of San Francisco saw flashing warning signs about the 405 Freeway closure between San Francisco and Santa Cruz before they headed to Santa Monica, where they munched on corn dogs Sunday afternoon. The L.A. stereotype of people glued to their cars hasn't "really been validated on our trip here," Wattiker said. 
 
 Yet some motorists grew frustrated when they were unexpectedly entangled in additional street closures in West Los Angeles and downtown for the Herbalife Triathlon. About 2,500 competitors swam, biked and ran from Venice Beach to the finish line at Staples Center. The triathlon was far less publicized, leading to angry denunciations of the event's timing and unsuspected congestion. 
 
 "You could just see the frustration in people's faces," said Nicole Rempola, a Santa Monica College student who was thwarted by triathlon barricades at the intersection of Fairfax and Pico. 
 
 ken.weiss@latimes.com 
 
 rick.rojas@latimes.com 
 
 alexandra.zavis@latimes.com 
 
 Contributing to this report were Times staff writers Ari Bloomekatz, Andrew Khouri, Christine Mai-Duc, Kate Mather, Laura Nelson, Joseph Serna and Matt Stevens.
– A surprise section of bridge gave way, narrowly missing construction workers during Los Angeles' "Son of Carmageddon," but the latest phase of a massive highway reconstruction project otherwise went off without a hitch—and without the predicted nightmare traffic jams. A 10-mile stretch of Interstate 405 had to be closed over the weekend so part of the 50-year-old Mulholland Drive bridge could be taken down to make way for a wider road. While the crew was working on one section of the span, another section plummeted to the earth, reports CNN. But no one was injured, and LA Mayor Antonio Villaraigosa has already labeled the work a "resounding" success. "Our hope and expectation was that it would be Carmaheaven 2," boasted Villaraigosa. The highway has already reopened today ahead of schedule, but it hasn't been easy street beating the rush-hour deadline as crews scrambled to squeeze into two days what should have taken weeks, filling potholes and paving three southbound lanes along Sepulveda Pass. "This was the mother of all public works projects," a Los Angeles County supervisor grumbled to the Los Angeles Times. The work is part of a $1 billion, four-year project to install what Villaraigosa calls the "longest carpool lane in the nation."