第一章 土的物理性质及工程分类(教材习题)
1-1 解
(1)A曲线:卵石或碎石 (>20mm)占100﹣77=23% 砾粒 (20-2mm)占 77﹣50=27% 砂粒 (2-0.075mm)占 50﹣10=40%
粉粒 (<0.075mm)占 10%
(2)A曲线较平缓,说明A土土粒粒度分布范围广,颗粒不均匀,故级配良好;而B土曲线较A土曲线陡,说明其粒度分布范围窄,土粒均匀,故级配不良。 (3)A土
d10?0.08 d30?0.6 d60?3.6 Cu?d60/d10?3.6/0.08?45?5
22 Cc?(d30)/(d10?d60)?(0.6)/(3.6?0.08)?1.25
在1-3之间,故A土级配好 B土
d10?0.15 d30?0.35 d60?0.74
54.9?5 Cu?d60/d10?0.74/0.1?22/(0.7?40.15?)1.10 Cc?(d30)/(d10?d60)?(0.35)
只满足一个条件,故级配不良
1-2 解:
ms?119g mw?m?ms?127-119?8g w?mw/ms?8/119?6.72% e?Gsρw(1?w)/ρ?1?2.7?1?(1?0.0672)/1.76-1?0.637 ρ?m/V?127/72?1.76g/cm3
ρsat?(Gs?e)?w/(1?e)?(2.7?0.637)/(1?0.637)?2.04g/cm3 ρ'??sat??w?1.04g/cm3 ρd?ms/V?119/72?1.65g/cm3
n?e/(1?e)?0.637/(1?0.637)?38.9% Sr?wGs/e?0.0672?2.7/0.637?28.5%
比较密度:ρsat>ρ>ρd>ρ'
1-3 解
Vv?Vs , e?Vv/Vs?1
?d?Gs?w/(1?e)?2.68?10/(1?1)?13.4kN/m3
Vv?Vw?sat?(Gs?Vv)?w/(1?e)?(ds?e)?w/(1?e)?(2.68?1)?10/(1?1)?18.4kN/m3
w?Ww/Ws?Vw?w/VsGs?w?1v/Gs?1/2.68?37.3%
1-4 解 设V?1m
3Ws??d?V?11kN
Vs?Ws/(ds?w)?11/(2.7?10)?0.407m3
Vv?V?Vs?1?0.407?0.593m3
w?Ww/Ws Ww?w?Ws?0.5?11?5.5kN Vw?Ww/?w?5.5/10?0.55m3Va?Vv?Vw?0.593?0.55?0.043m3
1-5 解:
饱和土 e?w?Gs ?sat?(Gs?e)?w/(1?e) 即 e?0.4Gs 18?(Gs?e)/(1?e)?10 以上两式联立求解 解得 e?1.05 Gs?2.65
1-6解
w?Ww/Ws?(W?Ws)/Ws 可求得w?16%时,W?21.64N时土粒的质量Ws?W/(1?w)?21.64/(1?0.16)?18.655N
其中水量为Ww?w?WS?0.16?18.655?2.985N
'当w'?25%时,土中水量为Ww?w'?Ws?0.25?18.655?4.664N
因此增加的水量?Ww?4.664?2.985?1.679N
1-7 解:
3设饱和土为V?1m V?Vs?Vw?1
饱和土w?Ww/Ws?Vw/VsGs?0.6 由上两式联立可得: Vs?0.382 Vw?0.618
Ws?VsGs?w?0.382?2.7?10?10.314kN
Ww?w?WS?0.60?10.31?6.186kN
当w?15%时, 需要土W?(w?1)WS?1.15?10.314?11.86kN 其中水量 Ww?wWS?0.15?10.314?1.547kN 故增加水的重量为?W?6.186?1.547?4.64kN
1-8 解:
e?1 e?Vv/Vs Vv?VS V?1m3 Vv?VS?0.5m3
Sr?Vw/Vv Vw?Sr?Vv?0.8?0.5?0.4m3
3''当水蒸发掉一半时Vw?Vw/2?0.4/2?0.2m Vv?Vw/sr?0.2/0.9
V?0.5?0.2/0.9?0.722?72.2%
1-9 证:
?/?d?1?(W/V)/(Ws/V)?1?W/Ws?1?(W?Ws)/Ws?Ww/Ws?w
1-10 解:
e?Gs?w(1?w)/??1?(2.65?10?(1?0.073))/17.1?1?0.663
?dmin?Ws/V?29.85/2000?0.0149N/cm3?14.9kN/m3
?dmin?GS/?w/(1?emax) 14.9?2.65?10/(1?emax) emax?0.779 ?dmin?Ws/V?32.5/2000?0.0163N/cm3?16.3kN/m3
?dmin?GS/?w/(1?emin) 16.3?2.65?10/(1?emin) emi?n0.62 6Dr?(emax?e)/(emax?emin)?(0.770?0.663)/(0.779?0.626)?0.758 Sr?Gs??w/e?2.65?0.073/0.663?29.2%
1-11 解:
在压实以前 n?e/(1?e)?0.72/(1?0.72)?0.419
3在1m2的地基面积中,土粒体积为VS?(1?n)V?(1?0.419)?5?2.91m
在压实以后,土粒体积减少0.3m
3n?(V?VS)/V?(5?0.3?2.91)/(5?0.3)?0.381
e?n/(1?n)?0.381/(1?0.381)?0.616
此时Dr?(emax?e)/(emax?emin)?(0.75?0.616)/(0.75?0.52)?0.583
1-12 解:
mw?23?15?8g w?mw/ms?8/15?0.533?53.3%
Ip?wL?wP?40?24?16 IL?(w?wP)/(wL?wP)?(53?24)/16?1.813
10?IP?17 粉质粘土 IL?1 流态
1-13 解:
(1)A土IP?30 > B土IP?11 故A土粘粒含量多
(2)由??Gs??w(1?w)/(1?e)?ds??w(1?w)/(1?w?Gs/Sr) 因为是饱和土 Sr?100%?1
A土 ??2.69?10(1?0.53)/(1?0.53?2.69)?16.97kN/m B土 ??2.71?10(1?0.26)/(1?0.26?2.71)?20.03kN/m B土的天然重度大 (3)?d??/(1?w)
3A土 ?d?16.97/(1?0.53)?11.09kN/m 3B土 ?d?20.03/(1?0.26)?15.89kN/m
33B土的干重度大
(4)因为是饱和土 e?w?Gs A土 e?0.53?2.69?1.43 B土 e?0.26?2.71?0.70 A土的孔隙比大
1-14 解:
因为大于2mm粒径的土粒占总质量的(11?5)?16%?50%。按表1-7颗粒级配所示属砂土,而>2mm粒径的颗粒只占总质量16%?25%,故该土样不是砾砂,而>0.5mm粒径的颗粒占总质量(16?39)?55%?50%,故该土样定名为粗砂。
第二章 地基的应力部分习题解答
3.1 细砂、粗砂分界线处:?CZ?16.4?3?49.2kPa 粗砂 n?en?e??2/3 1?e1?nG?(1?w)2.65?10?(1?0.2)??Sw??19.08kN/m3
1?e1?2/3 水位线处?CZ?49.2?19.08?2.4?94.8kPa 粗砂与粘土分界处?sat?(GS?e)?w(2.65?2/3)?10??19.9kN/m3
1?e1?2/3 ?CZ?94.8?(19.9?10)?2.1?115.6kPa 粘土w?mwVwV??0.6?e?w?0.6?2.73?1.638 msGS?VSVS
?sat?(GS?e)?w(2.73?1.638)?10??16.56kN/m3
1?e1?1.638 粘土与泥岩分界处?CZ?115.6?(16.56?10)?3?135.28kPa 泥岩顶面?CZ?135.28?10?5.1?186.28kPa
搜索“diyifanwen.net”或“第一范文网”即可找到本站免费阅读全部范文。收藏本站方便下次阅读,第一范文网,提供最新小学教育土力学课后习题部分答案(重庆大学出版社)(1)[1] 全文阅读和word下载服务。
相关推荐: