【正文】 在 Oakland 機場的高速公路上，在沿著 Pajaro and Salinas 和的橋上，在 Moss Landing 的 San Jose State Marine 站都被液化破壞了。在近來的 Loma Prieta 地震的破裂中，不僅僅包括這種水平成分的位移，也包括一個西南和東北方向的上推，斷層陡峭地插入這個地區(qū)的西南端。 歷史地震 San Andreas Fault 是朝著西北方向延伸的，從 California 灣向 San Francisco 北部的 Cape Mendocino 延伸 了 800 英里。這個區(qū)域是受到最嚴重破壞的地區(qū)。 地震和地質(zhì) 里氏 級地震的震中位于 Santa Cruz 的東南部 10 英里處，沿著 San Andreas Fault，在 Santa Cruz 山接近 Loma Prieta 的地方。這些建造很多都完全崩潰了，更多的已經(jīng)完全不能修理了。它剛剛被升級，有一個新的地基。在 Santa Cruz，損壞發(fā)生在土質(zhì)較差的地方。在 Santa Cruz 的煙囪損壞沒有那么頻繁，主要限制在舊的，不牢固的煙囪上。老住宅樓（尤其是 40 年代以前的），由于它們?nèi)狈εc地基的正確連接，或者它們的地板上升，這些地板是由相對較脆弱的跛墻支撐的。有的結(jié)構(gòu)不適當?shù)慕ㄖ镏詻]有遭受嚴重破壞，是因為它們所在的大多數(shù)地區(qū)地殼的運動都不是很劇烈。由于它和在 Hollister 的上傾斜建筑是一起的，這個番茄加工公司的鋼架結(jié)構(gòu)和遭受了嚴重的破壞，貨物也受到了嚴重損失。有一個建筑物，它一半的屋頂都居住著人的，也倒塌了，引起了內(nèi)部的廣泛的破壞。 上千棟上傾斜建筑物位于受影響的地區(qū)。這座建筑近來被加以防震措施，在它周圍加上了鋼筋帶。 外文翻譯 指導教師： 趙同峰 專業(yè)班級：土木 07— 3 班 學 號： 0702090306 姓 名： 王巍 沈陽建筑大學 土木工程學院 英文資料 The October 17, 1989 Loma Prieta Earthquake October 1989 Commercial Structures The Loma Prieta Earthquake and its subsequent aftershocks resulted in widespread damage to a variety of mercial structures. A large geographical area was affected, as is typical for an earthquake of this magnitude. The affected area enpasses eight counties, from Monterey and San Benito in the south to San Francisco, Alameda, and Contra Costa in the north. In total, building structures experienced damage over an area of approximately 3,000 square miles. Although damage was widespread, it was also quite sporadic. As would be expected, areas closest to the epicenter including Hollister, Los Gatos, Santa Cruz, and Watsonville experienced the most concentrated damage. Farther away, heavy damage was generally limited to buildings of very poor construction founded on soft soils that failed or amplified the earthquake ground motions. This is similar to the effects noted in the 1985 Mexico City Earthquake. Earthquake effects also tended to be highly directional. Most damage occurred within a narrow band that extends northwest to southeast, approximately paralleling the San Andreas Fault. Thus many munities along the margins of San Francisco Bay escaped serious damage. Unreinforced Masonry Buildings As has been observed in past California earthquakes, the most concentrated and severe damage to building structures occurred in unreinforced masonry (URM) bearingwall buildings. URM buildings, constructed of woodframe roof and floor systems supported by thick unreinforced brick walls, were monly constructed throughout California until the 1930s, when the adoption of building codes with seismicresistive provisions prevented their further development. As a result, URM buildings are typically found in the central business districts of older California cities Failures of URM buildings result from inadequate anchorage of the masonry walls to roof and floor diaphragms, as well as the limited strength and ductility of the basic building materials and poor construction workmanship. Deterioration of the sandlime mortar and wood framing due to weather exposure frequently contributes to poor performance. California has recently enacted legislation (SB 547) requiring cities to identify URM buildings and develop plans to reduce the risk they present. Damage to URM buildings in the Loma Prieta Earthquake ranged from dramatic collapses near the epicenter to fallen parapets in Martinez, more than 70 miles away. Lifethreatening collapses also occurred in Hollister, Los Gatos, Oakland, and the San Francisco financial district. The roofs and floors in many buildings with collapsed walls seemingly defied gravity by continuing to stand after losing their loadbearing support. Generally, buildings with throughwall anchorage to floor and roof framing performed better than buildings without this feature. Most URM buildings in the region survived the earthquake without collapse or obvious substantial damage. However, field investigations show that many of these structures have experienced extensive cracking of the masonry and are therefore weakened. If not repaired, some of these buildings are likely to collapse in future earthquakes. URM buildings with more than three or four stories were generally constructed with steel frames to carry the gravity loads. Masonry walls in these buildings were primarily provided for building closure and partitions and to add lateral shearresistance to the structure. These steelframe infill masonry buildings have generally performed better in past California earthquakes than the smaller bearingwall buildings. Noheless, these buildings were included in California legislation addressing the unreinforced masonry hazard. In the Loma Prieta Earthquake, many steelframe buildings with infill masonry walls performed quite poorly, although no collapses occurred. Several major structures of this type in San Francisco and Oakland experienced extensive damage including partial loss of the exterior masonry walls, shattering of interior clay tile partitions, and cracking and spalling of terracotta veneers. Concrete Buildings Many older reinforced concrete structures have very limited seismic resistance. These buildings tend to be quite heavy, resulting in large seismic forces. In addition, concrete itself is quite brittle and requires extensive amounts of reinforcing steel to perform properly in earthquakes. Most concrete structures designed prior to the mid1970s do not have adequate reinforcing steel to ensure good performance. Termed nonductile concrete structures by engineers, these structures have collapsed in past earthquakes. The Cypress Viaduct structure that dramatically collapsed was a nonductile concrete structure. Fortunately, there are relatively few nonductile c