第一章
1-1:
已知:V=72cm3 m=129.1g ms=121.5g Gs=2.70 则: w?m?ms129.1?121.5??6.3%ms121.5
m129.1g?*10?17.9KN/m3v72m121.5Vs?s??45cm3?s2.7???g?
VV?V?Vs?72?45?27cm3?sat??satg?msat?V?ms1.0*27?121.5g?wVg?*10?20.6KN/m3VV72????sat??w?20.6?10?10.6KN/m3ms121.5g?*10?16.9KN/m3 V72则?sat????d????d?1-2:
已知:Gs=2.72 设Vs=1cm3
?s?2.72g/cm3ms?2.72gms2.72g?*10?16KN/m3V1.7m?V?2.72?0.7*1???g?sVwg?*10?20.1KN/m3V1.7则??????w?20.1?10?10.1KN/m3
?d??dg?当Sr?75%时,mw??wVVSr?1.0*0.7*75%?0.525gw?mw0.525??19.3%ms2.72mw?ms0.525?2.72g?*10?19.1KN/m3V1.7???g?1-3:
ms??dV?1.70*103*8*104?13.6*107kgmw?msw?13.6*107*20%?2.72*107kgV挖?ms?mw
?13.6*107?2.72*107?85000m331.92*101-4:
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甲:
Ip?wL?wP?40?25?15设Vs?1则ms??s*Vs?2.7gmw?2.7*30%?0.81g又因为 Sr?100%?VV?mw?0.81?w??ms?mw2.7?0.81??1.94g/cm3Vs?Vw1?0.81ms2.7??1.48g/cm3Vs?Vw1.81
???g?19.4KN/m3?d??d??dg?14.8KN/m3e?Vv?0.81Vs乙:
Ip?wL?wp?8设Vs?1则ms??sVs?2.68gmw?msw?2.68*22%?0.4796g则VV?0.4796cm3ms?mw2.68?0.4796??2.14g/cm3
Vs?VV1?0.4796ms2.68??1.84g/cm3Vs?Vw1.4796?????g?2.14*10?21.4KN/m3?d??d??dg?1.84*10?18.4KN/m3e?VV?0.4796Vs??甲??乙 ?d甲??d乙 e甲?e乙 Ip甲?Ip乙 则(1)、(4)正确 1-5:
G??d?sw 则
1?e2 / 22
e?Gs?w
Sr??d?1?2.7*1?1?0.591.70wGs22%*2.7??1?85à.59
所以该料场的土料不适合筑坝,建议翻晒,使其含水率降低。
1-6:
Dr?(?d??dmin)?dmax
(?dmax??dmin)?d3式中Dr=0.7 ?dmax?1.96g/cm3 ?dmin?1.4g 6c/m则可得:?d?1.78g/cm3 1-7:
设 S=1, 则Vs?Sh?h 则压缩后:
则Vw?ms?VsGs?2.7h mw?msw?2.7h*28%mw?w?2.7h*28%
Vs?Vw?2.7h*28%?h?1.95 则 h?1.11cm ?hV?2.0?1.11?0.89cm
e?VVhV0.89???0.8 Vsh1.111-8: 甲:IL?w?wpwL?wpw?wpwL?wp?45?25?1.33 流塑状态
40?2520?25??0.33 坚硬(半固态)
40?25乙:IL??Ip?wL?wp?15 属于粉质粘土(中液限粘质土) 乙土较适合作天然地基 1-9:
A甲?Ip甲P0.002甲Ip乙P0.002乙?53?36?0.31?0.75 属非活性粘土 5570?35?1.3?1.25 属活性粘土 273 / 22
A乙??乙土活动性高,可能为伊利石,及少量的高岭石,工程性质乙土的可能较
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第二章
2-1解:
根据渗流连续原理,流经三种土样的渗透速度v应相等,即vA?vB?vC 根据达西定律,得:RA?h?hA?h?RBB?RCC LALBLC??hA:?hB:?hC?1:2:4
又
?hA??hB??hC?35cm
??hA?5cm,?hB?10cm,?hC?20cm
V?kA?hA?1*10?3cm/s LAV加水?V*A*t=0.1cm3
2-2解:
icr?Gs?12.70?1??1.076 1?e1?0.58?h20?1*9.8*?6.53N L302-3解:
(1)土样单位体积所受的渗透力j?1*rw(2)icr?Gs?12.72?1??1.055 1?e1?0.63?h20i???0.667
L30i?icr 则土体处于稳定状态,不会发生流土现象
(3)当i?icr时,会发生流土破坏,即h?icr时 Lh?L*icr?30*1.055?31.65cm
水头差值为32cm时就可使土样发生流土破坏 2-4解:
(1)hA?6m,hC?7.5m,hB?hA?hC?6.75m 2rw*?h?3.675kN/m3 l?h?0.625 (2)若要保持水深1m,i?Lj?rw*i?而Q?Akv?20*10*1.5*10*0.625?1.875*10m/s
?8?635 / 22