2007級本科生巖石力學大作業(yè)題目

《巖石力學》大作業(yè)1.作業(yè)題目結合所學的《巖石力學》課程及相關知識，利用給出的測井數據，對地層力學參數、地應力、地層坍塌壓力與破裂壓力進行分析計算，作出地層力學參數、地應力、地層坍塌、破裂壓力剖面，形成結課作業(yè)報告。2.已知條件地層測井數據（見附表）；地層孔隙壓力當量密度為1.03g/cm3上覆主應力在3000m處地層當量密度為2.23g/cm3；地應力實測值：在3025m處實測水平最大主應力大約59MPa，水平最小主應力大約49MPa；測井過程中鉆井液密度為1.35g/cm3；巖心抗壓強度試驗結果：井深（m）圍壓值（MPa）破壞強度（MPa）3030016.125106.53110022.630127.13.要求利用自然伽馬測井數據簡單分析地層巖性，合理設定或求取Biot系數；利用測井數據計算分析地層的彈性模量、泊松比；根據抗壓試驗結果，依據莫爾-庫侖準則計算單點的粘聚力和內摩擦角，根據實驗結果調整合理的系數，利用測井數據計算粘聚力、內摩擦角與地層抗拉強度的連續(xù)剖面；采用地層密度積分方法計算上覆主應力，根據地應力實測數據分析水平構造應力系數，采用適當模型計算水平主應力大小，得出上覆地層應力、水平最大和最小主應力剖面；采用直井完整性地層坍塌、破裂壓力計算模型，不考慮滲流作用，計算地層坍塌壓力和破裂壓力；輸出結果中單位的使用：地層強度參數采用MPa為單位，地應力、坍塌壓力、破裂壓力采用當量泥漿密度為單位；巖石力學作業(yè)說明1.利用自然伽馬測井數據簡單分析地層巖性，合理設定或求取Biot系數根據自然伽瑪測井數據，由公式（1）、（2）可計算出不同井深處巖石的泥質含量。式中，——泥質的體積含量；IGR——泥質含量指數；GR，GRmin，GRmax——分別表示目的層的、純砂巖層的和純泥巖層的自然伽瑪讀數值，這里取GRmin=30，GRmax=140。GUCR——希爾奇指數，對于第三系地層取3.7，老地層取2。這里取GCUR=3.7。關于Biot系數的設定：當；；。2.利用測井數據計算分析地層的彈性模量、泊松比由聲波時差數據算出縱、橫聲波速度，然后求出，。并通過動靜轉換得到，。（km/s）（3）（4）（5）（6）（7）式中，、——分別為縱波速度與橫波速度。、——動態(tài)、靜態(tài)彈性模量；、——動態(tài)、靜態(tài)泊松比。3.利用測井數據計算粘聚力、內摩擦角與地層抗拉強度的連續(xù)剖面。C---粘聚力，----內摩察角A，a，b為經驗系數，根據實測數據反算地層單軸抗拉強度和抗壓強度。4.計算地應力（1）上覆巖層壓力的計算上覆巖層壓力梯度一般分段計算，密度和巖性接近的層段作為一個沉積層，即（2）水平主應力的計算（使用黃榮樽法（六五）：式中：是反應兩個水平方向上構造應力大小的常數，即構造應力系數。由實測地應力反算5.地層坍塌壓力和破裂壓力（1）坍塌壓力保持井壁穩(wěn)定的坍塌壓力公式式中,（2）破裂壓力附件：測井數據井深(m)聲波時差（us/ft）伽馬測井密度(g/cm3)300088.34191.8662.3914300189.14389.0472.3867300290.46997.2972.3789300393.84697.4732.3597300494.66298.0542.3552300594.33297.0582.357300694.732107.432.3548300794.99490.2022.3533300895.04290.4772.3531300994.71499.392.3549301093.91990.8732.3593301193.86399.9832.3596301294.025101.422.3587301394.593103.212.3555301496.535109.062.345301596.74100.412.3439301697.264102.832.3411301798.259104.672.3358301896.26197.8122.3465301995.957101.12.3481302095.098107.812.3528302195.35994.9612.3514302295.01195.7152.3533302395.512104.892.3505302496.04996.1512.3476302596.233105.92.3466302696.12396.0092.3472302795.61699.0592.35302895.85598.2572.3487302994.896102.992.3539303095.79790.6582.349303195.731101.112.3493303294.83598.7022.3542303395.05991.3182.353303496.15103.252.3471303596.4897.6192.3453303696.16594.1162.347303796.38697.5862.3458303897.178101.22.3416303998.283102.322.3357304095.903101.342.3484304198.32104.822.3355304296.877104.42.3432304397.289107.972.341304498.078100.982.3368304597.79394.6892.3383304699.919100.252.3272304799.04797.6582.3317304899.10697.922.3314304999.106100.42.3314305099.097106.892.3315305198.417103.62.335305298.718102.082.3334305396.935105.032.3429305496.50492.3142.3452305597.092107.542.342305696.03994.0382.3477305795.90794.3712.3484305896.36998.7282.3459305995.715100.182.3494306096.759102.232.3438306199.152107.512.3312306296.50399.8312.3452306394.593.3182.3561306494.717101.192.3549306594.29198.3682.3572306694.70297.7812.355306795.64596.2542.3498306896.648100.122.3444306998.94495.1552.3323307097.973102.512.3374307196.324103.482.3461307295.13796.7372.3526307395.06287.152.353307495.97893.4362.348307595.65196.3722.3498307694.87699.6012.354307795.629104.412.3499307895.28187.1042.3518307996.144105.412.3471308095.27298.2852.3518308195.45899.2182.3508308295.292101.892.3517308395.99193.072.3479308496.375100.642.3459308596.64391.2932.3444308696.80495.8262.3436308798.09995.0442.3367308896.85697.372.3433308995.688109.832.3496309096.743102.212.3439309197.802102.982.3383309296.435105.592.3455309396.67696.2952.3442309496.677104.482.3442309596.61294.7162.3446309695.914103.422.3483309795.53893.912.3504309896.578101.072.3448309997.025100.612.3424310096.492100.892.3452310196.45994.9622.3454310296.751100.532.3438310396.299.0382.3468310497.339100.492.3407310596.284107.582.3463310694.38395.7612.3567310792.77288.3642.3657310893.86793.1272.3596310995.918109.782.3483311097.765103.122.3384311197.66996.8112.339311295.59299.9572.3501311399.029103.082.3318311499.03107.752.3318311599.03104.722.3318311699.05599.62.3317311798.969101.222.3321311899.132103.162.3313311998.458100.832.3348312096.421106.392.3456312196.3231052.3461312294.2396.762.3575312398.206103.292.3361312497.71198.5632.3387312597.214103.712.3414312696.324108.042.3461312796.35396.7592.346312896.11897.2092.3472312997.47893.0372.34313097.194103.512.3415313198.655114.852.3338313296.467107.232.3454313396.81296.9172.3435313495.6105.832.35313596.526101.262.345313696.735103.572.3439313796.47497.1742.3453313896.639100.612.3444313996.04795.592.34763