【正文】
監(jiān)測(cè)系統(tǒng)( GEOMOS)是一個(gè)典型的、每天 24小時(shí)運(yùn)行的邊坡監(jiān)測(cè)網(wǎng)絡(luò)。人為失誤,棱鏡損害或測(cè)站的移動(dòng)同樣可以影響測(cè)量精度。斜坡頂部形成的裂縫是一個(gè)明顯的不穩(wěn)定的標(biāo)志。 另一個(gè)常用監(jiān)測(cè)裂紋運(yùn)動(dòng)的方法是用便攜式有線延伸儀。長(zhǎng)度太大的線由于下降或熱膨脹產(chǎn)生誤差,所以調(diào)整和修正很有必要。電子延伸儀可以鏈接到一個(gè)報(bào)警系統(tǒng)。額外的裂縫,通過地面松動(dòng)將有可能削弱整個(gè)區(qū)域,同時(shí)也會(huì)導(dǎo)致測(cè)量不準(zhǔn)確。因此,宜不斷監(jiān)測(cè)地下水水位,以及孔隙水壓力,以助于評(píng)價(jià)邊坡穩(wěn)定性 [5]。水壓力的信息對(duì)斜坡設(shè)計(jì)和安全維護(hù)是至關(guān)重要的。一個(gè)測(cè)斜儀是由一個(gè)放置在地面上穿過預(yù)期運(yùn)動(dòng)區(qū)域的套管組成。 [10]表示,從收集到的關(guān)于傾斜儀資料可用于下列各項(xiàng): 1)找到剪切帶; 2)確定是否是平面的剪切或旋轉(zhuǎn)的; 3)確定是否沿剪切帶運(yùn)動(dòng)是不變的,加速,或減速。時(shí)域反射儀是一種新的來監(jiān)測(cè)斜坡運(yùn)動(dòng)方法 [11 14]。 TDR 的基 本原理類似于雷達(dá)的。脈沖信號(hào)的大小隨著運(yùn)動(dòng)規(guī)模變化。所有 TDR監(jiān)測(cè)設(shè)備都在表面; 快速和遠(yuǎn)程監(jiān)控: TDR數(shù)據(jù)可以通過遠(yuǎn)程通訊傳輸, [16]間隔性的記錄和掃描可進(jìn)行遠(yuǎn)程操控來檢驗(yàn)區(qū)域利益。在安裝上已經(jīng)取代了傳統(tǒng)的測(cè)斜儀。激光掃描儀是一個(gè)獨(dú)立有效的測(cè)量工具。它記錄了小到可達(dá) 10毫米到 1000米的斜坡表面的運(yùn)動(dòng)。該系統(tǒng)在該公司在巖土小組確定的地點(diǎn)進(jìn)行連續(xù)的 24 小時(shí)的遠(yuǎn)程掃描,每天收集測(cè)量點(diǎn)數(shù)百個(gè)。 SiteMonitor 同樣用在德比爾斯公司南非金伯利鉆石礦進(jìn)行高精度斜坡測(cè)量,同時(shí)可幫助確定在坑墻壁的潛在故障。 4)大量點(diǎn)迅速進(jìn)行監(jiān)控,而不是單棱鏡的測(cè)量 。如果被監(jiān)視的站點(diǎn)分布太廣或 站點(diǎn)之間如果發(fā)生位移,一個(gè)邊坡失穩(wěn)的早期跡象可能被忽視。此外,巖壁植被減少了該位置的位移測(cè)量精度,困擾用戶,使得在其他測(cè)量工作時(shí)缺乏信心。 邊坡監(jiān)測(cè)雷達(dá)在異常檢測(cè)和校正模塊時(shí),邊坡監(jiān)測(cè)系統(tǒng)包括:大氣校正模塊,可校正用于大氣變化;擾動(dòng)檢測(cè)模塊,當(dāng)在斜坡運(yùn)動(dòng)測(cè)量時(shí),測(cè)量誤差導(dǎo)致的干擾識(shí)別引起的。 英文原文: Surface Mine Slope Monitoring Techniques Kayode S. Osasana,b and Thomas B. Afenia,b Abstract:Excavation of rock initiates a reaction of movements in the rock mass. if this movement, which is a precursorto mine slope failure is timely and accurately monitored, accidents, destruction of equipment, loss of ore reserves, closure of the mine and sometimes loss of life that are the resultant effects of surface mine slope failure will be averted. Laser scanner, total station, crack meter, visual inspection, sirovision and lately monitoring radar are some of the techniques that have been developed for monitoring the displacement (. movement) of mine slope. This paper reviewed the importance of slope monitoring vis224。 (3) to serve as a warning system as to which areas of the pit are unstable。 provide additional geotechnical information regarding slope behavior. Slope Monitoring Steps Slope monitoring process normally constitutes five steps. It starts with monitoring requirements. This is to establish the objectives, need, advantages (both economic and safety advantages), researching historic problems as case studies and finally preparing a report to decisionmakers motivating the need for monitoring and identifying the benefits that can be expected [4]. The second step is to establish the project requirements, which follows from the pit design and a risk assessment. The oute of this will state the probability of failure and the variables that will most likely contribute to such failure. The third step will take account of these variables in designing the monitoring system, considering instrumentation and implementing the monitoring system [5]. The fourth step is the actual measurement and recording of field data. Measuring techniques and frequencies, accuracy, precision and personnel responsibilities are very important at this stage. Fortunately, this would have been taken care off during the design of the monitoring system. The fifth and final step is interpretation and reporting of monitoring data. The reporting of results and documenting of events, decisions, design changes and costbenefit analysis plete the monitoring process. Surface Measurement The surface measurement involves some techniques among which are: survey work and tension crack mapping. Survey Network. A survey work consists of target prisms placed on and around areas of anticipated instability on the pit slopes with one or more control points for survey stations. These stations need to be located close enough to the pit crest so that all prisms can be readily seen。 3) Determine whether movement along a shear zone is constant, accelerating, or decelerating. Time Domain Reflectometry (TDR). Time domain reflectometry is a new approach to monitoring slope movement [11 – 14]. Originally developed to locate breaks and faults in munication and power lines. TDR is used to locate and monitor slope failures. The technology uses coaxial cable and a cable tester. The basic principle of TDR is similar to that of radar. The cable tester sends an electrical pulse down a coaxial cable grouted in a borehole, when the pulse encounters a break or deformation in the cable, it is reflected. The reflection shows as a “spike” in the cable signature. The relative magnitude, rate of displacement and the location of the zone of deformation can be determined immediately and accurately. The size of the spike increase correlates with the magnitude of movement。 (4)immediate deformation determinations: Locations of any movement are determined immediately using TDR. Additional data reduction is generally not necessary and the cables can be used to quantify rock movement as well as distinguish shear and tension [17]。 4) thousand of points are monitored rapidly rather than single prism locat