Dropped into train of elder brother railroad 1981 bridge accident, it is serious passenger train contingency when happened in China to become elder brother railroad on July 9, 1981, cause more than 275 people die or be missing, also be the accident with most heavy casualties of the passenger on Chinese railroad history. On July 9, 1981 before dawn 1 when make 30 minutes, benefit of the big affluent that cross a river child according to amount to channel to erupt mud-rock flow (velocity of flow is as high as 13.2m/s, unit weight amounts to 2.32t/m3, and included many Ju Li among them, diametical 8m above person amount to tens of piece [2]) , more than 100 meters 17 meters channel mouth tall, chief benefit child destroy according to Da Daqiao. Will leave for straight fast passenger train 442 times of Chengdu by the level ground in case on July 8, on July 9 before dawn 1 when 27 minutes, on schedul arrives be apart from Chengdu the Gan Luo of 236 kilometers stands, 1 when 35 minutes of stations send signal of car setting out, but train has not give station station unexpected power failure. This matter ever caused a driver to notice, but final decision still moves by convention. 1 when 41 minutes, 442 train in the Buddhist nun day station and Chengdu leave for Jin Jiang to stand (today kapok stands) 211 times express is handed in after the meeting, by the Buddhist nun day stand aside goes out. After a minute, the Buddhist nun day station stands to ahead Wu Sihe (today Chinese source stands) interrupt to the phone discovers during 442 times train signs up for a dot, circuit is illogical, cannot contact. 1 when 45 minutes, train leaves go up to cross river right bank greatly, with speed per hour 40 kilometers (25 miles) speed sails include channel into the grandma, having turninging after channel curve, the room of patrol and guard a road or railway by the gully that train driver Wang Mingru discovers to channel is exported suddenly collapses, and cannot see ahead advantage child glance according to what amount to big bridge rail, apply instantly urgent apply the brake. Because lead to a section of a highway of big bridge from channel,be declivous paragraph, gradient amounts to 14 ‰ , train fails to stop before bridge floor discontinues the position. 1 when 46 minutes, 12 13 two east wind diesel locomotive, luggage barrow, mail car and 3 cars railroad car (9 reach 11) fall from bridge dropping, among them engine and 11 in dropping to cross a river greatly to 13 cars, date and 10 9 cars are dropped in the bank, compartment of 8 semi-cushioned seat coach are bumped to give rail by powerful wallop inside the channel of either end of a bridge, capsize outside channel mouth. Incident causes 275 people to die in all or be missing, operation of the railroad that become elder brother interrupts 15 days. Concerned respect is built in accident former address temporarily railway bridge, include channel at the grandma new interest is built by the entrance child according to amount to channel. Temporarily railway bridge will restore have transport service on July 24 at of the same age. In May 1984, the profit that grows 1465 meters child according to when amounting to channel to use build complete be open to traffic 3 years. Benefit is worn below this new channel child according to the bottom hill body that amounts to channel, kept away from the mud-rock flow menace to train of by way of. Original grandma bag channel discards in postaccident and keep up to now, its rail and road block are demolished; And the profit that leave child according to Da Daqiao pier criterion still stand erect up to now.