作者

盧志杰、柯永彥

摘要

2022年關山–池上地震主要包含分別發生於9月17日與9月18日、震央位於關山與池上兩地、芮氏規模為6.6與6.8之兩起強震。為了留下寶貴之地震特性與災損資料，供各界參考與研究，基金會特針對此地震發行專刊。 本次專刊共納入11篇文章，內容包含地體構造、震源機制、地表破壞觀察、地工災害踏勘調查、震害區大地環境特性調查以及災後復舊策略與工程等，由地震學出發，涵蓋地震引致現象與其衝擊，並及於工程層面。各篇作者透過實際觀測、調查、研究或復舊工程之參與，分享其對於此次關山–池上地震的見解與看法，相信其寶貴的經驗及成果對從事地震研究與地震防災工程之學界與工程界朋友深具參考價值。

作者

周中哲

摘要

臺灣位於環太平洋地震帶，地震威脅無可避免，約每二十年即發生一次大災型地震；尤其東部地區因地質上屬歐亞大陸板塊與菲律賓海板塊之聚合邊界，地震發生率高於他處。歷年來多起地震災害已造成可觀之人員傷亡與經濟損失，包括死傷最慘重的1935年新竹-台中烈震，死亡達3,276人，房屋全倒達17,907戶；經濟損失最高之1999年集集地震，死亡達2,415人、建築物全倒達51,711戶；近年則有造成台南維冠大樓倒塌及百人以上傷亡，並造成多處土壤液化災情之2016年美濃地震，與2018年造成雲門翠堤大樓等建築物崩塌與人員傷亡之花蓮地震等。2022年9月17日與18日間，在台東地區又發生芮氏規模各為6.4與6.8之關山地震與池上地震，造成花蓮南部與台東北部數棟建築與數座橋梁全倒或受損，一人死亡及逾百人受傷，並於玉里斷層與池上斷層沿線引致多處地表破裂，造成鋪面與工程構造物損傷與地下管線斷裂。
前述地震中之傷亡主因為建築物之倒塌，其同時造成民眾失去家園、公共服務(如學校、醫院)與產業營運受影響甚至停擺；此外，橋梁、管線、電力設備等基礎建設之受損亦對民生與經濟有莫大衝擊。因此，必須確保建築物與橋梁等工程結構物具備足夠耐震能力，以降低震災對社會之衝擊。對於新建結構物，可由耐震設計規範著手，對地震力進行合理之考量，並對結構物耐震性能之要求與技術提出完善規定。國震中心多年積極修訂建築物與橋梁耐震設計規範，除基於過去地震災害經驗及研究成果進行必要調整外，也導入性能設計理念，使耐震設計能更全面且合理，達到安全性、修復性、使用性之平衡。近年國震中心亦成立設備管線組，投入民生經濟至為重要之設備與管線耐震研發，期能更進一步提升國家社會之整體防災韌性。
另一方面，眾多的既有工程構造物因建造年代不一，可能有耐震能力無法符合現行規範之情況，拆除重建因費用高、工期長、又有居民安置問題，故耐震補強為常採用的方案。臺灣從十多年前即積極推動公有建築物耐震補強，以校舍為例，國震中心於2003年全力投入校舍耐震補強計畫之準備工作，後續由教育部申請專案經費，由2009年至2022年間投入新臺幣約1,284億，在縣市教育局處與各級學校行政人員努力與國震中心協助下，共協助各縣市完成約一萬棟校舍之耐震能力提昇工程，今年可全面完成公立高中職以下校舍結構耐震能力補強。
然而，對於私有建築，其屬私人財產而不易強制執行耐震能力提升工作，且常因所有權人眾多而較難達共識。但私有建築也常有老劣化或結構不良等情況，如前述維冠大樓、雲門翠堤大樓、與此次池上地震之建物倒塌均與軟弱底層有關。國震中心在2005至2006年間曾參與「既有建築物耐震評估及補強促進條例」草案之研擬；在2016年美濃地震後，國震中心將具軟弱底層之住商混合大樓評估為優先耐震補強對象；2018年花蓮地震與2022年池上地震又接連發生軟弱底層建物倒塌，有鑑於此，國震中心曾邀集產學界共同商討，建議應對私有供公眾使用且具一定規模以上之軟弱底層老舊建築物進行耐震評估與補強。目前建築物耐震補強技術研發已臻成熟，期許透過產官學研界共同創造有利環境，促進我國私有建築耐震評估與補強工作之推展，建立安全耐震的家園。
此次關山-池上地震也提醒我們花東縱谷諸多斷層的威脅。事實上，1951年在花蓮、台東一系列規模7左右的強震，共造成近百人死亡與超過千人輕重傷，房屋全倒與毀損達四千棟。因此，花東縱谷的地震風險與震災防治課題，需要地震科學界與工程界持續的關注與投入。國震中心設有地球科學與大地工程組，對於地震學、地震危害度、場址效應等議題均持續進行相關研發，此次地震所造成之災害不如1951年地震序列嚴重，但所提供之資訊將能對提升研究者對花東縱谷地區地震特性之瞭解。
地工技術基金會成立以來，戮力投入大地工程技術與議題分享交流，貢獻良多。國震中心亦關注工程地震學與大地地震工程，與國內外地震觀測網與地震學研究機構均有合作，在臺北與臺南設有能重現各類地震運動之高性能地震模擬振動台與模擬土質地盤之大型剪力盒，因應離岸風場地質調查需求在臺南設立土壤力學實驗室，並與中央大學土木系離心模型實驗室持續合作。為發展臺灣綠能產業，國震中心2021年起積極與國科會、國研院、經濟部、氣象局、台電、海洋中心，學界及產業界商討國內研發量能，研擬2024~2027年中長期發展規劃，獲國科會支持並匡列113年預算於「離岸風機結構智慧防災監測平台建置」新興政策計畫，內含綠能設施測試新實驗室建置，包括480g-ton地工離心機及20~40m長之風機結構葉片測試等新研究設備。前述計畫規劃過程受許多大地、海洋及結構工程界朋友協助才能順利推動，未來非常歡迎土木與海工界朋友共同參與及支持國震中心新實驗室建置，讓臺灣能有更巨大研發量能來發展地工技術、深海地質、地震、綠能風機、及AI防災監測等跨領域相關研究及人才培育。

英文篇名

The Central Range Fault System: Knowledge from the Surface Rupture Characteristics of the September 2022 Guanshan-Chihshang Earthquake Series

作者

徐澔德、王昱、周海寧

關鍵字

縱谷斷層、中央山脈斷層、玉里斷層、關山－池上地震、地表破裂

摘要

臺灣東部花東縱谷中，除了大家所熟知的縱谷斷層系統之外，位於縱谷西側，中央山脈東麓前緣的中央山脈斷層存在與否，以及其可能的構造特性長期以來一直是學界的一大爭議。2022年9月在縱谷南段發生了關山－池上地震，藉由此次地震的地表破裂特性，我們認為中央山脈斷層不但存在，其特性亦較過去的認知複雜許多。過去由1951年11月縱谷中南段地震地表破裂所繪製的玉里斷層，實則為中央山脈斷層系統中，一個向西傾，具有左移分量的逆斷層分支。本次地震的震源可能位在中央山脈斷層系統中一個較深部的分支上，除了在玉里斷層上出現了地表破裂之外，在縱谷斷層系統的淺部也產生了誘發變形。縱谷中南段的兩個主要斷層系統皆有在未來產生地震災害的可能，需要多加注意。

英文摘要

Along the Longitudinal Valley in eastern Taiwan, the well-known Longitudinal Valley fault system is a major active fault of Taiwan. However, except for this fault, whether there is a Central Range fault along the western edge of the valley or not has long been debated. Based on the observations of surface rupture characteristics of the September 2022 Guanshan-Chihshang earthquake, we suggest that not only does the Central Range fault exist, but the fault may also be a more complex system than previously thought. The Yuli fault, which was identified based on surface ruptures of the November 1951 earthquakes in the south-central Longitudinal Valley, is likely a branch of the Central Range fault system, with left-lateral and reverse motion. The hypocenter of the 2022 earthquake was likely located on a deeper branch of the system, and was accompanied by surface ruptures on the Yuli fault and induced deformations on the Longitudinal Valley fault. The two major active fault systems in the south-central Longitudinal Valley both pose important earthquake hazard potentials in the future.

英文篇名

The Preliminary Tectonic Study of Central Part of Longitudinal Valley with Guanshan-Chihshang Earthquake Surface Rupture and Subsurface Geological Data

作者

顏一勤、陳文山、顏君毅、黃韶怡、徐乙君、石乃文、陳志壕、曾雅筑、朱耀國

關鍵字

關山-池上地震、地表破裂、槽溝剖面、鑽探剖面

摘要

本文主要利用作者所調查「關山-池上地震」期間造成地表破裂現象的特徵，再考慮其地表破裂位置的延伸連續性，共劃分出二層坪-寶橋大華段、電光-竹田段、崙天-東里段、長良-松浦段、船仔山-春日段、大禹-三民段等六段地表破裂跡。並參考前人研究所發表於上述地表破裂跡位置附近的槽溝剖面與地質鑽探剖面等地下地質資料，探討本次地震的發震構造與現階段於花東縱谷中段已知的活動斷層間的關係。最後，本文認為此次的「關山-池上地震」事件應為中央山脈斷層系統再次活動所造成，且因「關山-池上地震」發生時，於池上斷層發震構造震源區並未具有規模夠大，而能造成池上斷層活動的地震，故本文推測此次地震所造成位於池上斷層位置的地表破裂，係屬於中央山脈斷層活動後，沿池上斷層面滑移，而非屬池上斷層本身的發震構造有活動的現象。

英文摘要

In this paper, authors divided six segments of the surface rupture, which caused by the Guanshan-Chihshang Earthquake, depending to the characteristics and the extending. With reference to the published data such as trenching profiles and drilling profiles , we discussed the relationship between the tectonic and the surface rupture faults in the central part of Longitudinal Valley of eastern Taiwan. Finally, we conclude that the Guanshan-Chihshang Earthquake should be caused by the reactivation of the Central Range fault system, and no evidence of reactivation of the Chishang fault in this earthquake event.

英文篇名

Source and Strong Motion Characteristics of the Guanshan and Chihshang Earthquakes in Eastern Taiwan

作者

林哲民、黃雋彥、張毓文、趙書賢

關鍵字

關山地震、池上地震、震源、強地動、近斷層速度脈衝

摘要

關山地震與池上地震在東臺灣造成最大震度6強之強烈地動，此強烈地動也造成許多嚴重地震災害，包含多座建築物及橋梁之倒塌。依據此次地震序列之震源分布、主震震源機制及區域地質構造研判，此次關山地震及池上地震之震源破裂面都是高角度向西傾之左移斷層，一般認為是由花東縱谷西邊之中央山脈斷層活動所引致，也進而誘發了縱谷斷層沿線的地震活動及地表破裂。透過強震站實測地震資料推估之全臺地動分布顯示，關山地震的強地動區域由震央往南延伸至關山、池上及鹿野一帶，池上地震則是由震央池上大範圍往北延伸至富里、玉里及瑞穗一帶，兩地震在多個近震央強震站都觀測到長週期及高地動速度之近斷層速度脈衝，而這兩次地震所引致的主要災情位置也與強地動分布有顯著之關連性。

英文摘要

The Guanshan and Chishang earthquakes induced strong motion with seismic intensity 6+ and serious damage, including several collapses of buildings and bridges, in eastern Taiwan. According to the hypocenters of the earthquake sequence, focal mechanisms of the mainshocks, and regional geology structure, the source ruptures of the two earthquakes are both a left-lateral fault with a high westward-dipping angle, which is supposed to correspond to the Central Range Fault. The earthquakes also triggered some aftershocks and surface ruptures along the Longitudinal Valley Fault. The strong motion distribution, estimated based on the observation of the strong motion station around Taiwan, shows that the high ground motion intensities of the Guanshan earthquake extended to the south from the epicenter, whereas those of the Chihshang earthquake extended to the north of the epicenter. There were several strong motion stations that observed significant near-fault velocity pulse with long period and high ground velocity. The severe damage of the earthquakes all happened near the region with high intensity or velocity pulse.

英文篇名

Remote Sensing Observation and Derivative Analysis of Surface Deformation in Guanshan Chishang Earthquake

作者

王國隆、林俊廷、李苡宣、張為光、郭安妮

關鍵字

遙感探測、差分干涉分析、地表破裂

摘要

2022年9月發生之關山池上地震為近年來難得之案例，在災害調查使用之遙感探測研究方法與技術相較於921地震之後均有長足進步，本文以合成孔徑雷達(Synthetic Aperture Radar, SAR)分析方法為主，無人載具方法為輔，進行關山池上地震地表變形追蹤觀察與分析。
衛載合成孔徑雷達分析是近年來高度發展的遙測技術，由於雷達波為電磁波，具有不受天候影響、可大面積探測與固定周期等特性，廣泛運用於災害調查之中，SAR 紀錄相位資訊經由差分干涉(Differential Interferometric SAR, DInSAR)後有機會獲得厘米級的變形資訊。
本研究以 DInSAR 分析方法為始，利用波長23.6公分之ALOS2合成孔徑雷達資訊分析地震地表變形，輔以波長5.3公分之Sentinel-1 合成孔徑雷達衛星，成功偵測地震時之地表破裂跡位置與受力變形位置，對於DInSAR分析受限位置，以無人載具補充分析斷層推擠之結果。最後嘗試以短基線法萃取同震變形，精緻化地表變形分析結果，並嘗試提出以地表變形速率預測地震之假說。

英文摘要

The Guanshan-Chishang earthquake that occurred in September 2022 is a rare case in recent years. Compared with the 921 earthquake, the remote sensing detection research methods and technologies used in disaster investigation have made great progress. This article uses Synthetic Aperture Radar (SAR) as the main method, supplemented by the unmanned vehicle method, and the surface deformation tracking observation and analysis of the Guanshan-Chishang earthquake are carried out.
Satellite synthetic aperture radar analysis is a highly developed remote sensing technology in recent years. Because radar waves are electromagnetic waves, they are not affected by weather, can detect large areas, and have fixed periods. They are widely used in disaster investigations. SAR records phase information through Differential Interferometric SAR (DInSAR), and it is possible to obtain centimeter-level deformation information.
This research starts with the DInSAR analysis method, using the ALOS2 synthetic aperture radar with a wavelength of 23.6 cm to analyze the surface deformation of the earthquake, supplemented by the Sentinel-1 synthetic aperture radar satellite with a wavelength of 5.3 cm, successfully detecting the location of the surface rupture and the affected area during the earthquake. For the force deformation position, for the limited position of DInSAR analysis, the results of fault pushing are supplemented by unmanned vehicles. Finally, we try to extract the coseismic deformation with the short baseline method, refine the results of the surface deformation analysis, and try to put forward a hypothesis of predicting earthquakes based on the surface deformation rate.

英文篇名

Primary Exploration of the Surface Rupture and Co-seismic Deformation of the 2022 Guanshan- Chihshang Earthquake

作者

徐乙君、盧志恆、張中白、黃韶怡、顏一勤、顏君毅

關鍵字

關山-池上地震、中央山脈斷層、玉里斷層、池上斷層、同震地表變形、雷達差分干涉技術

摘要

2022年9月17日和18日分別在關山和池上發生規模6.6(ML)及6.8(ML)的淺層地震，造成花蓮及台東多處建物及橋樑損毀，並產生多處地表破裂，破裂分布從北到南長達70多公里，地表破裂發生位置除了集中於已知的玉里斷層和池上斷層沿線外，亦有許多破裂分布在非斷層跡附近。本篇文章針對此次地震造成之地表變形進行地表同震破裂調查，並配合雷達差分干涉分析結果，對大區域構造先有初步了解。透過實地考察可將同震地表破裂依發生時間和運動特性大致分成四類，第一類為主要分布於寶華-二層坪一帶，主要為0917關山地震所致；第二類主要分布在池上斷層沿線既有的斷層崖坡，產生向西逆衝的破裂，部分區域伴隨左移運動；第三類為具明顯的左移分量的地表破裂，並產生西側抬升的變形；第四類分布在玉里斷層沿線，以左移運動為主。透過不同波長的雷達衛星影像進行差分干涉，可觀察此次地震的地表變形分布情形，除了受到既有活動斷層之影響外，亦有跨越海岸山脈的變形行為，顯示縱谷下方構造可能有向外海延伸。此次地震影響範圍大，不論是餘震、地表破裂，及同震變形都相當複雜，皆需要靠後續的分析才得以獲得更多資訊。

英文摘要

Two shallow earthquakes of magnitude 6.6(ML) and 6.8(ML) occurred in the Guanshan and Chihshang areas on September 17th and 18th, 2022. The earthquake caused damage to infrastructures, the toppling of buildings and bridges, and surface ruptures. The distribution of ruptures is more than 70 kilometers long from Ruisui to Luye. In addition to the known Yuli Fault and Chihshang Fault, many ruptures are distributed near non-fault traces. In this paper, we have a preliminary understanding of the regional structure by investigating surface ruptures and the co-seismic deformation results of differential Interferometric SAR. After our field investigation, the co-seismic surface rupture can be roughly divided into four types according to the occurrence time and motion characteristics. The first type rupture was distributed in the Baohua -Ercengping area, which was mainly caused by the 0917 Guanshan Earthquake. The second type rupture was mainly distributed in the existing fault scarp along the Chihshang fault, which rupture was westward thrusting, and some areas are accompanied by left-slip movement. The third type rupture had a prominent left-slipping component and an uplifting on the west side. The fourth type rupture was distributed along the Yuli fault, mainly through left-slip movement. Through differential interference of radar satellite images of different wavelengths, we observed the distribution of co-seismic surface deformation. In addition to being affected by existing active faults, the deformation behaviors across the Coastal Range indicate that the structure below the Longitudinal valley may extend to the sea. The earthquake events affected a large area, and the distribution of aftershocks, surface rupture, and co-seismic deformation were quite complicated. More information needs to be obtained through follow-up analysis.

英文篇名

Assessing the Allowable Displacement Performance of crossing Active Fault Bridges in Dongli Area : Feedback from Guanshan-Chishang Earthquake Fault Ruptures

作者

柳鈞元、劉育良、林承翰、謝沛宸、林銘郎、詹佩臻

關鍵字

關山-池上地震、跨斷層橋梁、現地調查、容許位移、交通選線、分離元素法

摘要

2022年9月17日及18日花東地區發生2起規模6以上的地震，本次地震造成若干鐵公路橋梁受到程度不一的損壞，其中的臺鐵新秀姑巒溪橋自選線規劃到新線結構設計上都因鄰近池上斷層有諸多考量，該橋在本次地震中雖未發生落橋破壞，但15跨橋面版中最大位移量逾1.3公尺，且多數橋墩之止震塊與支承墊因橋面版位移(最大達60公分以上)而損壞斷裂。本文藉由無人機輔助調查東里地區地表破裂跡分布與鐵公路橋梁受損情形，並採用分離元素法模擬跨斷層橋梁結構型式和線型交角兩個變因，以量化分析新秀姑巒溪橋受地表破裂跡之影響，可作為未來跨活動斷層橋梁容許位移評估、鐵公路橋梁改線或減緩與調適工法等方面之參考依據。

英文摘要

On September 17th and 18th, 2022, two earthquakes of magnitude 6 or higher struck eastern Taiwan resulting in severe damage to railways and highways bridges. This study utilized unmanned aerial system to assist in investigating the distribution of surface rupture traces in the Dongli area and document the damage of the cross-fault infrastructure. Despite taking the Chishang fault into consideration during the route selection and structural design stage, the TRA New Xiuguluan bridge suffered severe damage due to the surface rupture of Guanshan-Chishang earthquake. Discrete element modeling was conducted to quantitatively evaluate the effects of route selection and structural type on the interaction between fault rupture and bridge structure. This article may serve as references for allowable displacement performance assessment, mitigation and adaption design of crossing active fault bridges in the future.

英文篇名

Is Liquefied Soil a Natural Seismic Isolation Material ? Observations on the Failure Modes of Bridge Piers during the 2022/09/18 Chihshang ML 6.8 Earthquake

作者

黃俊鴻、朱柏林、黃梓益、邱晨佑、盧志杰、楊炫智、鄧源昌、陳冠羽、周昕成、游騰瑞

關鍵字

池上地震、液化土壤、高寮大橋、新秀姑巒溪鐵路橋

摘要

本文報導2022/09/18池上地震花蓮玉里高寮大橋與鐵路新秀姑巒溪橋之橋墩受震破壞模式的觀察與相關記錄。其中，高寮大橋的EP2與EP4橋墩破壞疑似由土壤液化之基礎破壞所引起，新秀姑巒溪橋之SP3橋墩周圍亦有明顯土壤液化現象。在這些橋墩的表面與上方大梁沒有明顯的震損，推測係因土壤液化的減震效應所引致，惟尚需後續調查驗證之。本文重點包括橋墩受震破壞模式的分類，橋墩與基礎尺寸之量測，相關土壤液化現象的記錄與試驗，表面波震測與微震試驗結果等，期供後續相關研究參考。最後建議未來應進行之調查與研究工作。

英文摘要

This paper reports the observation and related records of the earthquake damages to the the piers of the Gaoliao Bridge and to the superstructures of the Xinxiuguluanxi Railway Bridge in the 2022/09/18 Chihshang Earthquake. Among them, the damage of the EP2 and EP4 piers of the Gaoliao Bridge is suspected to be caused by the foundation failure induced by soil liquefaction. There are also traces of soil liquefaction around the SP3 pier of Xinxiuguluanxi Bridge. However, no obvious damage to the pier body and girder of these piers is found. It is presumed to be caused by the seismic-isolation effect of liquefied soil. The content focuses on the classification of pier failure modes for bridges, the measured dimensions of bridge piers and foundations, the records of soil liquefaction phenomena and the related laboratory tests, the results of MASW and micro-tremor tests. The above documents can be used as a reference for subsequent related research. Finally, it is suggested that the further investigation and research work should be carried out in the future.

英文篇名

Ground Characteristics in Hualien and Taitung using Microtremor Data

作者

劉博翔、吳建宏

關鍵字

微振、水平-垂直頻譜比、場址效應、關山-池上地震

摘要

本研究前往花東地區，調查2022年9月17日、18日發生的關山-池上地震受災區地盤之場址效應，以及建築物振動頻率和地盤動態特性之間的關係。調查地點包含高寮大橋地表、7-ELEVEN(玉明門市)、春日國小及三個臺鐵火車站(池上站、東里站、玉里站)。調查方法是量測地盤微振後，以單站水平-垂直頻譜比法評估地盤卓越頻率與放大係數。分析結果顯示，除了7-ELEVEN超商、池上車站沒有明顯場址效應，其餘地點均有放大作用引發結構破壞的可能性。另外，7-ELEVEN超商與東里車站，地盤卓越頻率接近建築物振動頻率，因此結構體與地盤之間的共振行為是日後防災的重點。

英文摘要

This study investigated the site effect and the coupling dynamic behavior of the ground and the local structures in the structural damage areas on September 23 and 24, 2022 caused by the Kuanshan-Chishang earthquake. The study sites included Gaoliao bridge, convenience store (7-ELEVEN), Chun-Rih elementary school, and three railway stations (Chi-Shang station, Dong-Li station, and Yu-Li station). The single-station Horizontal-to-Vertical Spectral Ratio (HVSR) was applied to evaluate the predominant frequency and amplification factor of the ground using in-situ microtremor measurement data. The analysis results showed that the ground in all structure damage zones has remarkable site effect, except the 7-ELEVENT convenient store and Chi-Shang station. In addition, the ground predominant frequency is close to the fundamental frequency of the buildings at the convenience store (7-ELEVEN) and Dong-Li station. Therefore, further studies are required to clarify the resonance of the ground and the damaged buildings in the next step as a key issue for the local disaster prevention.

英文篇名

Investigation and Recovery Strategy of Provincial Highway 20 after 918 Chishang Earthquake

作者

王慶雄、陳克劼、蕭秋安、張嘉興、陳俊定、徐士捷

關鍵字

917關山地震、918池上地震、邊坡重力變形、侵蝕溝

摘要

台20線南橫公路為台灣三大橫貫公路之一，貫穿東西部兩區域之重要道路，由於沿線地質條件變化大，尤其位於東側山區之路段，地形除受地質構造影響外，亦受台灣四季氣溫日夜差異大所為，因此岩體風化程度高、節理發達、非常破碎，故於98年莫拉克風災時本路段受到嚴重重創，後經過13年之修復，於111年5月1日重新有條件開放通車；然而111年9月18日發生池上地震，強大的地震力造成多處邊坡落石或岩屑崩滑等規模不一的災害，於地震後第一時間至埡口以東路段，針對地震災點進行現地勘查，並整合地震以外其他影響邊坡災損之致災原因進行探討，進一步規劃修復策略及整治構想，以及供其他類似公路案例之參考。

英文摘要

Southern Cross-Island Highway (Provincial Highway No. 20) is one of the three major highways traversing Taiwan. It is an important road running through its east and west regions. Due to the considerable variations in geological conditions along the route, especially in the mountainous road section on the east side, the terrain has not only been affected by geological structures, but also by the significant changes in Taiwan's four seasons. Due to the large temperature fluctuations between day and night, the rock mass endures a high degree of weathering, leading to well-developed joints, and a high proneness to brittleness. This section was therefore particularly severely damaged during the Typhoon Morakot in 2009. After 13 years of restoration, the highway section was completed and reopened on May 1, 2022, to be stricken again by the Chishang Earthquake which occurred on September 18, 2022. The strong earthquake force caused damage of various scales, such as falling rocks on slopes and debris avalanches. On-site surveys of the earthquake destruction points – particularly on the segment east of Yakou – were conducted; and an integrated approach proposed to consider disaster causes which result in slope damage other than the earthquake, as well as further restoration strategies planned and renovation ideas, all of which is discussed in this article to serve as reference for other projects facing a similar set of problems.

英文篇名

The Investigation and Emargency Repair Works for Laklak River Bridge and New-Xiuguluan River Bridge of TRA

作者

呂斌豪、林舜元、周行健、陳仲俊

關鍵字

池上地震、新秀姑巒溪橋、樂樂溪橋、橋梁搶修

摘要

臺鐵花東線因2022年09月18日規模6.8之地震受損，因樂樂溪橋8座橋墩損傷，新秀姑巒溪橋15跨主梁錯位，致使玉里-富里間之鐵路交通局部中斷。經震災後之現場勘查及評估後擬定兩階段之搶修目標，第一階段以盡速恢復鐵路交通運行為目標，第二階段再依據現行規範進行橋梁安全評估與補強以符合現行耐震規範之要求。基於第一階段之目標，樂樂溪橋損壞之橋梁墩帽以鋼板包覆方式進行修復，新秀姑巒溪橋則以國內軌道工程首次使用之「頂昇橫移」復位工法進行橋梁震後主梁錯位之修復。2022年12月28日已正式恢復花東線鐵路通車，並將視橋梁監測資料，逐步恢復列車之營運速度。

英文摘要

The Taiwan Railways Administration (TRA) Hualien-Taitung line was damaged by a magnitude 6.8 earthquake on September 18th, 2022. This caused damage to 8 pier caps of the Laklak River Bridge and 15 main beams of the New-Xiuguluan River Bridge, resulting in partial interruption of railway traffic between Yuli and Fuli. The repair plan includes two phases, with the first phase focused on restoring railway traffic as quickly as possible and the second phase on conducting safety evaluations and reinforcing the bridges to meet current seismic code. To achieve the main goal of first phase, the damaged pier caps of the Laklak River Bridge were repaired with covering by steel plates and the New-Xiuguluan River Bridge was repaired using a new technique, "top-lifting and transverse-shift" and steel seismic isolation blocks were installed. The emergency repairs were completed on December 28th, 2022 and the train's operating speed will be gradually restored based on monitoring data.

英文篇名

Characteristics of the 2016 Kumamoto Earthquake and the 2022 Guanshan-Chihshang Earthquakes

作者

黃有志、曾佳漢

關鍵字

熊本地震、關山-池上地震、走向滑移斷層、地表破裂

摘要

本文探討並比較2016年4月熊本地震，及2022年9月臺東關山-池上地震的特性。兩個地震序列都是先發生規模較小的有感地震，經過約一天再發生規模較大的致災性地震，並可能誘發附近的地震活動。斷層錯動以走向滑移為主，部分的斷層破裂帶較寬，可能被沖積層覆蓋而未被察覺，並伴隨不同形式的地表破裂，影響地震災情範圍。此外走向滑移斷層的地震活動、地表破裂與災害分布等特性，與臺灣常見的逆衝斷層不盡相同。期望藉由彙整兩個地震序列所獲得的資訊及啟示，對臺灣的活動斷層做更詳盡的調查，並提防在人口稠密的西部都會區，可能因許久未活動的走向滑移斷層，釀成嚴重的地震災情。

英文摘要

This article discusses and compares the characteristics of two earthquake sequences: the Kumamoto earthquakes that occurred in April 2016, and the Guanshan-Chihshang earthquakes that occurred in September 2022. In both earthquake sequences, the mainshocks occurred about one day after the first foreshocks, and nearby seismicity may have been triggered. The displacements were predominantly strike-slip and accompanied by different types of surface rupture, affecting the extent of seismic disasters. In addition, the seismicity, surface ruptures, and disaster distribution of strike-slip faults differ from those of thrust faults. By summarizing the information and insights gained from these two earthquake sequences, it is expected that more comprehensive investigations can be carried out on Taiwan's active faults. Some precautions should be taken against the potential disasters caused by future strike-slip events that may occur in densely populated urban areas in Western Taiwan.

作者

黃有志、丁權

摘要

作者

丁禕

摘要