采矿与安全工程学报
採礦與安全工程學報
채광여안전공정학보
JOURNAL OF MINING AND SAFETY ENGINEERING
2013年
4期
566-572
,共7页
刘杰%李建林%骆世威%蔡健%肖蕾%唐亮%汤天彩
劉傑%李建林%駱世威%蔡健%肖蕾%唐亮%湯天綵
류걸%리건림%락세위%채건%초뢰%당량%탕천채
载荷峰值%表观弹性模量%毫秒级%位移速率%“错峰”现象
載荷峰值%錶觀彈性模量%毫秒級%位移速率%“錯峰”現象
재하봉치%표관탄성모량%호초급%위이속솔%“착봉”현상
load peak value%apparent elastic modulus%millisecond level%displacement rate%“peak shifting”phenomenon
在加载速率随时间变化规律已知的前提下,研究得出不同载荷峰值下,表观弹性模量和加载力之间均呈线性关系,并随峰值增大,一次项系数递减、常数项递增的变化规律,指出该规律主要由岩体的压密程度和原始碎屑胶结物的强度决定。给出砂岩毫秒级位移速率的预测公式,通过计算位移速率和实测位移速率的比较证明该预测公式的合理性。比较发现,各加载段峰值点变形速率的峰值点均出现在1000和2000 ms 之间,超前于加载速率峰值时刻2500 ms,而在卸载段的峰值均出现在8000和9000 ms 之间,滞后于载荷变化速率峰值时刻7000 ms,说明“错峰”现象在不同载荷峰值下均存在,预测公式也能很好地解释和预测变载荷峰值下的“错峰”现象。根据推导公式,进一步进行岩样能量吸收统计,结果显示不同加载峰值下的预测毫秒级能量吸收过程与实测过程吻合较好,进一步说明了不同加载峰值下位移速率预测公式的适用性和合理性。
在加載速率隨時間變化規律已知的前提下,研究得齣不同載荷峰值下,錶觀彈性模量和加載力之間均呈線性關繫,併隨峰值增大,一次項繫數遞減、常數項遞增的變化規律,指齣該規律主要由巖體的壓密程度和原始碎屑膠結物的彊度決定。給齣砂巖毫秒級位移速率的預測公式,通過計算位移速率和實測位移速率的比較證明該預測公式的閤理性。比較髮現,各加載段峰值點變形速率的峰值點均齣現在1000和2000 ms 之間,超前于加載速率峰值時刻2500 ms,而在卸載段的峰值均齣現在8000和9000 ms 之間,滯後于載荷變化速率峰值時刻7000 ms,說明“錯峰”現象在不同載荷峰值下均存在,預測公式也能很好地解釋和預測變載荷峰值下的“錯峰”現象。根據推導公式,進一步進行巖樣能量吸收統計,結果顯示不同加載峰值下的預測毫秒級能量吸收過程與實測過程吻閤較好,進一步說明瞭不同加載峰值下位移速率預測公式的適用性和閤理性。
재가재속솔수시간변화규률이지적전제하,연구득출불동재하봉치하,표관탄성모량화가재력지간균정선성관계,병수봉치증대,일차항계수체감、상수항체증적변화규률,지출해규률주요유암체적압밀정도화원시쇄설효결물적강도결정。급출사암호초급위이속솔적예측공식,통과계산위이속솔화실측위이속솔적비교증명해예측공식적합이성。비교발현,각가재단봉치점변형속솔적봉치점균출현재1000화2000 ms 지간,초전우가재속솔봉치시각2500 ms,이재사재단적봉치균출현재8000화9000 ms 지간,체후우재하변화속솔봉치시각7000 ms,설명“착봉”현상재불동재하봉치하균존재,예측공식야능흔호지해석화예측변재하봉치하적“착봉”현상。근거추도공식,진일보진행암양능량흡수통계,결과현시불동가재봉치하적예측호초급능량흡수과정여실측과정문합교호,진일보설명료불동가재봉치하위이속솔예측공식적괄용성화합이성。
In this paper, under the premise that the rule of loading rate varying with time has been known, the research results show that there presents a linear relationship between the apparent elastic modulus and the loading force under different peak loadings, in which the first-order coefficient de-clines and the constant term increases as the growth of peak loadings. This rule is determined by con-solidation degree and original clastic cement strength of rock mass. Meanwhile, the predictor formula of displacement rate in millisecond level was put forward, its rationality was confirmed by comparing the calculated displacement rate and the observed values. After comparison, it suggests that the peak points of displacement rate in loading areas all appear between 1 000 ms and 2 000 ms, which is 2 500 ms ahead of the peak time of the loading rate, while the peak points of displacement rate in unloading areas appear between 8 000 ms and 9 000 ms, which is 7 000 ms lagging behind the peak time of the unload-ing rate. It explains that the ‘peak shifting’ phenomenon exists under different peak loadings and the predictor formula can well explain and predict this phenomenon. According to the derivation formula, the energy absorption statistics of rock samples were further carried out, which suggests that the pre-dicted millisecond level energy absorption process under different peak loadings agrees well with the measured process, and the applicability and rationality of the displacement rate predictor formula is fur-ther illustrated.