第
44
卷第
1
期
2012
年
1
月
四川大学学报(工程科学版)
JOURNAL
OF
SICHUAN
UNIVERSπY
(ENGINEERING
SCIENCE
E
D.町
ION)
文章编号:
1
∞
9-3087
(2012
)01
拍
69
-06
粉砂质泥岩的三轴蠕变试验研究
徐慧宁
1
,庞希斌
2
,徐进
l\
刘建锋
1
Vo
l.
44
No.1
Jan
.
2011
(1.四川大学水力学与山区河流开发保护国家重点实验室水利水电学院,四川成都
6
1(脱
5:2
.
五凌电力有限公司,湖南长沙
41
仪剧)
摘
要:为了揭示分布于北天山中西部的志留系上统紫红色粉砂质泥岩的蠕变特性,为拟建于此的某深埋越岭特
长隧洞的设计、施工,以及长期稳定问题评价提供依据,通过钻孔取样进行了三轴蠕变试验研究。试验在
5
台岩石
三轴蠕变试验机上进行,围压分别为
0
,
5
、
10
、
20
、
30
MPa
。试验取得以下主要成果:
1
)揭示了这类蒙古土岩的蠕变特
性可用西原模型加以描述,并由此建立了蠕变本构方程
;2)
采用曲线求参法求解了各流变参数
;3
)采用叠加原理与
等时曲线法获得了岩石的长期强度
;4
)各蠕变参数随围压的升高而增大,长期强度较瞬时强度降低的幅度亦随围
压升高而增大,单轴条件下降低
25%
,
30MPa
围压时降低
52%
;5)
抗剪断长期强度较瞬时强度降低了
ω%(
内聚
力)和
369
毛(内摩擦角)。这些成果为工程建设提供了科学依据,试验方法与成果整理方法可供同类工程参考。同
时,还通过常规试验获得了该类岩石的主要物理力学性能,这将有助于蠕变试验成果在其他工程中类比使用
。
关键词:粉砂质泥岩;三轴蝠变试验;西原模型;流变参数;长期强度
中图分类号
:U45
文献标志码
:A
Study
00
Triaxial Creep
T
臼
t
of Sllty Mudstooe
XU
Hui-ningl
,PANG Xi-bin
2
,
XU
lin
l
•
,
UU
lian:feni
(
1.
State
Key
l.ab.
of
Hy'
企咀
ilics
and
Mountain
Ri
ver
Eng.
,Sc
hool
of
Hydraulic
皿
d
Hydroel
回回
c
En
g.
,
Sichuan
Univ.
,
Chengdu
61α
陋,
China:2.
Wuling
Power
Co.
,
αumgsha
41α
剧,
α
lÎ
na)
Abstract:
Tri-axial creep test was carried out
on
borehole sarnpling basis in order to reveal the creep characteristics of purple silty rnud-
stone in the Upper Silurian
in
the center and
w
酬。
f
North Tianshan
,
and provide the basis
for
the designing
,
construction and long-
terrn stability evaluation of the proposed deep and long tunne
l.
Test was perforrned on five rock tri-axial creep test rnachines with the
confining pressure of 0
,
5
,
10
,
20 and
30
MPa
,
respectively.
Th
rough the study
,
the following resulted were achieved. Rock creep
characteristics
was
proved
to
be
describable
by
出
e
Xiyuan Model and a creep constitutive equation
wωestablish
for
this kind of rnud-
stone.
Th
e
cr
回
pp
缸
arneters
were gained
by
calculating them based
on
creep curves.
Lo
ng-terrn rock strength
wωobtained
by
supe
甲+
sition theorern and isochronous curve rnethod
,
and the confining pressure effect was revealed
on
the long-terrn strength.
Th
e creep pa-
rarneters increased
wi
由
the
increase of confining pressure
,
and the difference between long-terrn rock strength and instant rock strength
increased
by
259
毛
under
uni -axial
pr
,臼
sure
and
52%
under tri-axial pressure of 30
MPa
副
the
confining pressure increased.
Th
e long-
terrn
shearing
strength decreased
byω%
( cohesion) and
3~%
(intemal
friction an
g}
e)
cornpared with the instant
shearing
strength.
Th
e
回
results
provided a scientific basis
for
the engineering construction
,
and the test and result collation
rne
出
ods
were available
for
other sirnilar construction and research. Meanwhile
,
physic
a1
and rnechanic
a1
property of
silty
rnudstone was also obtained through rou-
tine tests
,
which helps
to
apply creep
test
陀
sult
to other sirnilar projects.
Key
words:
silty rnudstone; triaxial creep test; Xiyuan rnodel; rheological
p
町
arneters;
long-terrn strength
所有的工程材料都具有一定的流变特性,岩土
收稿日期
:2011
-01
-28
基金项目:国家自然科学基金资助项目
(5062013ω40)
:国际科
技合作资助项目
(2
即7D
F
B60
1
∞)
:国家重点基础研
究发展规划
"973"
资助项目
(2010C8226802)
作者简介:徐慧宁
(1983
一)
,女,博士生
.
研究方向:岩石力学与
工程.
E-mail:
huiningxu@gmai
l.
com
*通信联系人
E-mail
:
xujin@
田
u
.
edu.
cn
类材料也不例外。大量的现场量测和室内试验都表
明,对于软弱岩石以及含有泥质充填物和夹层破碎
带的松散岩体,其流变属性则更为显著;即使是比较
坚硬的岩体,如受多组节理或发育裂隙的切割,其剪
切蠕变也会达到相当的量值。用学术语言概括地
说,只要岩土介质受力后的应力水平值达到或超过
该岩土材料的流变下限,将产生随时间增长而发展
的流变变形
。
因此,在岩土工程建设中,就经常遇到