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    Please use this identifier to cite or link to this item: http://ir.cnu.edu.tw/handle/310902800/9270

    標題: 防墬設施安全性研究-著重於懸吊生理反應與懸掛錨定強度之研究
    A Study on the Safety of the Falling Prevention Installations--with Special Reference to the Physiological Response of Harness Suspension and the Pullout Force of Hanging Anchors
    作者: 蔡一主
    I-Chu Tsai
    貢獻者: 何先聰
    關鍵字: 防墜設施
    falling prevention installation
    pullout experiment
    embedded depth
    日期: 2007
    上傳時間: 2008-12-03 11:18:24 (UTC+8)
    摘要: 營造工作場所需進行高處作業,在無法獲得本質安全之條件下,若未設置必要且合適之防護設施,常有墜落災害發生,因此如何設置及安裝合適防墜設施,阻斷墜落之安全母索或安全網是營造業防墜計畫最重要之ㄧ環。
    懸吊量測結果由心電圖數據得知除了B種安全帶,其他安全帶在懸吊60秒至480秒時心跳、收縮壓及舒張壓均顯著差異性。安全帶在懸吊之後舒適性評估發現背負式舒適性都較佳,而繫身型(D種)及半身式(B種)安全帶在懸吊之後,全部受測者在問卷時100%全部否定,且均以腹部感到最疼痛之位置,甚至在懸吊時已有8人,當時感到不舒服或嘔吐或頭昏等症狀,實際使用上因座帶及胸帶等4個支撐點將其墜落後之衝擊力道分散,故在第ㄧ時間(墜落時)不會造成人員死亡,但仍有因衝擊力之大,造成人員心理上、生理上之極大反應; 此次研究另針對5人做持續懸吊90分鐘之試驗,以實際佐證背負式安全帶之安全性,若懸吊過久,則尚有致危之虞,值得各界注意。
    本研究以30 kN之油壓機對五種錨定裝置於不同條件下埋設於鋼筋混凝土版,進行拉拔強度試驗,紀錄錨定裝置被拉出之施力及與混凝土間之破壞模式。研究參數除五種不同類型之錨定裝置外,包括試體基材為四種混凝土抗壓強度( 13.7,20.6,27.4,34.3MPa )埋入不同深度( 63.5㎜、76.2 ㎜、101.6 ㎜ )每個試驗進行三次,合計完成204筆試驗,研究結果顯示內迫式或鎚入式錨定之拉拔強度無法達到安全母索錨定強度之要求,膨脹式及預埋螺紋式之拉拔遠高於其他錨定裝置;錨定埋入深度均不得小於76.2 ㎜ ( 3吋),否則錨定於較低混凝土強度時,抗拉強度無法達到法令之要求;各類錨定之拉拔強度與埋入深度及混凝土抗壓強度平方根成正相關,且可用線性迴歸式預測。
    Fatal work-related falls in the construction industry continue to remain one of the leading causes of the occupational accidents owing to working at unsafe high elevations or unguard opening and without using appropriated protection. It lesser obtain essential safety condition, so haw to erect the fitable and necessary fall arrest installation (safety nets, safety line and harness) is one of the most important of the fall accident prevention plan in the construction industry. The purpose of this study is to investigate the comfortable wear of harnesses by the suspended physiological responses and the legality of the anchors fastening to concrete member by pullout forces experiments.
    The research of the physiological response be divided two stages, first, is to measure the changes of ECG during the course of harness suspension and second, is to evaluate the comfort index and the sites of pain after harness suspension by questionaire. Sixty workers are recruited and divided into three groups equally in this study. There are five types of harnesses, including the economic whole-body harness(A-type), the half-body harness (B-type), the leg-belt whole-body harness(C-type), the waist-belt harness (D-type), and the abdomen whole-body harness (E-type). These harnesses are dressed for the individual and the ECG are monitored by the Multi-channel electrocardiography before and after hanging as well as at the time period of 60s, 120s, 180s, and 480 s during hanging. The comfort index and the sites of pain after harness suspension are also recorded by questionaire. The heart rate all accelerated significantly, during hanging at the time period of 60s, 120s, 180s, and 480s and recovered quickly after hanging but in C type harness it took 60s to 120s delay for heart rate to increase significantly. Also the heartbeat increased more in the B type harness than the other types during hanging at the time period of 60s, 120s, 180s, and 480s. The systolic pressure and the diastolic pressure were elevated during hanging at the time period of 60s, 120s, 180s, and 480s. These responses were very similar to the response of heart rate. And all of the workers tested denied the comfort ness of the B and D type in the questionaire. The most uncomfortably painful site is located at the abdomen. Ten of the workers felt uncomfortable or dizzy or vomited during the test, therefore the application of the B and D type should be highly careful and had better be aware. Though the full-body type harness can disperse the falling force to prevent death of the user in first time, but if the impact force is very large, it will also bring a huge psychological and physiological trauma to the user. Besides, five of the volunteers persisting suspensions of 90 minutes were also tested by using the type C harness in this study. The results revealed that though the whole-body type harness could save life for the instant of falling, but it could lead to severe condition for hanging longer than 90 minutes if there is no suitable auxiliary process to rescue the user as soon as possible.
    The anchor pullout experiments have finished 204 cases in this study. There are seven kind anchors , three of pre-erected anchors and four of post-installed anchors, fastened at the RC specimen with four compressive strength(13.7, 20.6, 27.4, 34.3 MPa) and three embeded depth( 63.5, 76.2, 101.6 ㎜) respectively. Each Group test with three times, are experimented by the movable hydraulic jack with loading capacity of 30 kN. The current research showed that the pullout force of the drop-in type anchors and knock-in type anchors, lesser than the legal necessary strength and should not be applied on the safety devices, came only from the friction between the bolt and concrete. The pullout force of the expansive type anchor and pre-erected spiral type anchor are not only far higher consistently than the other type anchors and appear stability. The imbedded depth of anchor cannot be smaller than 76.2 mm(3 inches), otherwise when the anchor is erected in the lower strength of concrete member,the pullout strength should not meet the legal necessary strength. The results revealed that the pullout force of all kinds of anchor in this study will positive correlation and can predict with emdedding depth and concrete compressive strength square root with the linear regression .
    關聯: 校內公開,校外永不公開
    Appears in Collections:[環境工程與科學系(所)] 博碩士論文

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