摩(mo)擦(ca)滑(hua)(hua)移(yi)(yi)(yi)隔(ge)(ge)震(zhen)是(shi)開發(fa)應(ying)用(yong)較早的(de)隔(ge)(ge)振技術(shu)之一,所用(yong)的(de)摩(mo)擦(ca)材料(liao)多(duo)為(wei)(wei)(wei)沙(sha)石、石墨等廉價(jia)材料(liao),標記(ji)經濟且簡單易行(xing)。摩(mo)擦(ca)滑(hua)(hua)移(yi)(yi)(yi)隔(ge)(ge)震(zhen)系(xi)統(tong)通(tong)常有(you)(you)隔(ge)(ge)離地(di)震(zhen)作用(yong)的(de)摩(mo)擦(ca)滑(hua)(hua)動(dong)機構(gou)(gou)和(he)限位(wei)(wei)復(fu)位(wei)(wei)的(de)阻(zu)尼向(xiang)心機構(gou)(gou)組成,多(duo)為(wei)(wei)(wei)平面(mian)滑(hua)(hua)移(yi)(yi)(yi)隔(ge)(ge)震(zhen)系(xi)統(tong)。該系(xi)統(tong)不(bu)能(neng)自動(dong)復(fu)位(wei)(wei),一般需要另外加設復(fu)位(wei)(wei)裝置(zhi),且滑(hua)(hua)動(dong)性(xing)能(neng)離散性(xing)大、不(bu)易控制(zhi),滑(hua)(hua)移(yi)(yi)(yi)量過大可(ke)能(neng)導致穿越隔(ge)(ge)震(zhen)層的(de)非結構(gou)(gou)構(gou)(gou)件(jian)破(po)壞,甚(shen)至可(ke)能(neng)發(fa)生滑(hua)(hua)移(yi)(yi)(yi)失穩,這極大地(di)阻(zu)礙了滑(hua)(hua)移(yi)(yi)(yi)隔(ge)(ge)震(zhen)的(de)發(fa)展。為(wei)(wei)(wei)了解決平面(mian)滑(hua)(hua)移(yi)(yi)(yi)系(xi)統(tong)不(bu)能(neng)自動(dong)復(fu)位(wei)(wei)問題(ti),Zayas等于1985年在(zai)美(mei)國加州大學伯克利分校研發(fa)了摩(mo)擦(ca)擺(bai)隔(ge)(ge)震(zhen)裝置(zhi),稱之為(wei)(wei)(wei)摩(mo)擦(ca)擺(bai)系(xi)統(tong)/支座(Friction Pendilum System/Bearing,簡稱FPS/FPB)。該裝置(zhi)不(bu)僅具有(you)(you)平面(mian)滑(hua)(hua)移(yi)(yi)(yi)隔(ge)(ge)震(zhen)裝置(zhi)的(de)對地(di)震(zhen)激(ji)勵頻(pin)率范圍的(de)低敏感(gan)性(xing)和(he)高穩定(ding)性(xing),特有(you)(you)的(de)圓弧(hu)滑(hua)(hua)動(dong)面(mian)還使其具有(you)(you)復(fu)位(wei)(wei)功能(neng),無(wu)需附設阻(zu)尼向(xiang)心機構(gou)(gou),故(gu)而在(zai)實際應(ying)用(yong)中更為(wei)(wei)(wei)簡便,且增加了隔(ge)(ge)震(zhen)裝置(zhi)的(de)可(ke)靠度。
摩(mo)擦(ca)(ca)擺(bai)隔震支(zhi)(zhi)座(zuo)(zuo)是將傳統(tong)的(de)(de)平(ping)面(mian)(mian)滑(hua)(hua)移(yi)隔震裝置的(de)(de)摩(mo)擦(ca)(ca)滑(hua)(hua)移(yi)面(mian)(mian)由平(ping)面(mian)(mian)改為球面(mian)(mian),從而可依靠自(zi)身(shen)重力自(zi)動(dong)(dong)回復。該支(zhi)(zhi)座(zuo)(zuo)主(zhu)要由上(shang)、下(xia)支(zhi)(zhi)座(zuo)(zuo)板和一個鉸接滑(hua)(hua)塊(kuai)(kuai)組(zu)成。摩(mo)擦(ca)(ca)擺(bai)隔震支(zhi)(zhi)座(zuo)(zuo)嵌在滑(hua)(hua)動(dong)(dong)容腔中的(de)(de)鉸接滑(hua)(hua)塊(kuai)(kuai)與(yu)滑(hua)(hua)動(dong)(dong)面(mian)(mian)具有相(xiang)同(tong)的(de)(de)曲(qu)率半徑,可與(yu)滑(hua)(hua)動(dong)(dong)面(mian)(mian)完(wan)全貼合,并使上(shang)支(zhi)(zhi)座(zuo)(zuo)在支(zhi)(zhi)座(zuo)(zuo)滑(hua)(hua)動(dong)(dong)時始終保(bao)持水平(ping)。滑(hua)(hua)動(dong)(dong)面(mian)(mian)上(shang)涂有低摩(mo)擦(ca)(ca)材料,如聚四氟(fu)乙烯(特氟(fu)龍)等(deng),可在滑(hua)(hua)動(dong)(dong)過(guo)程中耗散能量。當滑(hua)(hua)動(dong)(dong)界面(mian)(mian)受(shou)到的(de)(de)地震作(zuo)用超過(guo)靜摩(mo)擦(ca)(ca)力時,地面(mian)(mian)水平(ping)運(yun)動(dong)(dong)會促(cu)使滑(hua)(hua)動(dong)(dong)在其圓弧面(mian)(mian)內(nei)滑(hua)(hua)動(dong)(dong),從而迫使上(shang)部結構輕(qing)微抬高,發生單擺(bai)運(yun)動(dong)(dong)。然后(hou),支(zhi)(zhi)座(zuo)(zuo)會在自(zi)身(shen)受(shou)到的(de)(de)豎向荷載作(zuo)用下(xia)自(zi)動(dong)(dong)回復。
摩(mo)擦擺(bai)隔震(zhen)(zhen)支(zhi)座的水平力(li)為滑動(dong)面摩(mo)擦力(li)和上(shang)(shang)(shang)部結構沿滑道上(shang)(shang)(shang)升產生的恢(hui)復力(li)的合(he)力(li),而(er)(er)提供的恢(hui)復力(li)使(shi)支(zhi)座能(neng)依靠其承(cheng)受的重力(li)自(zi)(zi)動(dong)往(wang)中心位(wei)置回復,使(shi)地震(zhen)(zhen)響應得(de)到(dao)控(kong)(kong)制,并且(qie)該支(zhi)座的剛(gang)度中心有自(zi)(zi)動(dong)與(yu)隔震(zhen)(zhen)結構的質心重合(he)的趨勢,因(yin)而(er)(er)能(neng)在更大 程度上(shang)(shang)(shang)消除結構的扭轉運(yun)動(dong)。摩(mo)擦擺(bai)隔震(zhen)(zhen)支(zhi)座的周期、豎向承(cheng)載力(li)、阻尼比(bi)、側重位(wei)移和抗(kang)拉力(li)等指標可以進(jin)行單(dan)獨控(kong)(kong)制,該特性(xing)十分便于設計(ji)人員對隔震(zhen)(zhen)系統進(jin)行優化(hua)設計(ji)。