SHEAR STRENGTH (YULINDASARI, NURLY GOFAR)
ISBN No. : 978€02-17221-1-4
HIMPUNAhI AHLI TEKNIK TANAH INDONESIA
INDOtIESIAN SO(;lETY FOR GEOTECHNICAL ENGINEERING (ISGE)
MEMBER SOCIEY OF INTERNAT]ONAL SOCIETY FOR SOIL MECHANICS
AND GEOTECHNTCAL ENGTNEERTNG {TSSMGE}
SffiArewwMWMw36W
KGeotechnical Solution in Indonesia to Respond
the Challenge of Urbano Industry,
Infrastructure and Mining Developmentn'
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Proceedin g
l7'' Annual Scientific Meeting
Jakarta, l3-14 November 2013
('Geotechnical
Solution in Indonesia to Respond
the Challenge of Urban, fndustry,
Infrastructure and Mining Developmenttt
Editor
:
Hasbullah Nawir
Bigman Marihat Hutapea
YP. Chandra
Widjojo Adhi Prakoso
Hendra Jitno
Agus Setyo Muntohar
HIMPUNAN AHLI TEKNIK TANAH INDONESIA
INDONESIAN SOCIETY FOR GEOTECHNICAL ENGINEERING (ISGE)
Basement Aldevco Octagon, Jl. Warung Jati Barat Raya No. 75
Jakarta Selatan 12740
I7tt' Annual Scientifc Meeting
Jakarta. I 3-11 November 201 3
KATA PENGANTAR
Assalamulaikum Wr. Wb.
Para undangan, para pengurus Pusat dan Daerah Himpunan Ahli Teknik Tanah Indonesia.
para pembicara dan peserta Pertemuan Ilmiah Tahunan HATTI yang kami hormati,
Pertemuan llmiah HATTI tahun ini mengambil tema .6Geotechnical Solution in Indonesia
to Respond the Challenge of Urban, Industry, Infrastructure and Mining Development".
Saat ini pemerintah dan swasta semakin giat melakukan investasi pada sektor konstruksi, baik
untuk bangunan pekantoran, apartemen, MRT, pelabuhan, jalan bebas hambatan maupun
inlrastruktur untuk perlambangan. Hal ini berhubungan dengan program pemerintah clalam
konteks percepatan pembangunan ekonomi Indonesia. Terobosan baru dalam meniawab
masalah geoteknik berkembang semakin pesat dan menjadikan keterlibatan serta peran
Geotechnical Engineers semakin penting.
Selain mengangkat topik seminar yang berkaitan dengan aspek geoteknik dan perkembangan
riset serta teknologi terbaru sebagai pendukungnya, PIT XVII inijuga menggelar Workshop
GROUND IMPROVEMENT FOR DIFFICULT SUBSOIL CONDITIoNS.
Kegiatan seminar dan workshop ini diharapkan dapat memberi kesempatan kepada seluruh
peserta untuk berbagi informasi dengan para praktisi konstruksi khususnya di bidane
SAtu haTi tentang
geoteknik.
Fada kesempatan ini, atas nama seluruh anggota panitia penyelenggara, kami meneucapkan
terima kasih kepada GEOHARBOUR GROUP sebagai sponsor utama seminar dan trrirksht p
Fertemuan
Ilmiah HATTI tahun 2013. Ucapan terimakasih juga kepada para pembicara.
penulis makalah, para sponsor dan para peserta yang telah berpartisipasi untuk suksesn\a
PIT-XVII ini. Kami mohon maaf apabila dalam penyelenggaraan pertemLran ini eJa
kekurangan yang tidak berkenan.
Selamat berdiskusi dan semoga Pertemuan Ilmiah Tahunan
perkembangan profesi Geoteknik di tanah air.
Wassalamualaikum Wr Wb,
Panitia PIT - XVII
Dr. Ir. Wiwit nanayu
Ketua
ini dapat bermant-aat
basi
Annual Scienti/ic Nleeling
Jckarta, I 3-11 November 2013
l7'1'
SAMBUTAN KETUA UMUM
Assalamu'alaikurn Wr. Wb.
Salam Sejahtera bagi kita semua'
pembicara, dan saudara-saudara
Bapak wakil Menteri, Bapak Dirjen, para undangan, para
hormati, atas nama Pengurus
saya
peserta Peftemuan llmiah Tahunan XVII HATTI.yang
pusat HATl'l saya ucapkan terima kasih atas kedatangan Bapak/lbu sekalian di acara ini'
saya menyampaikan
yang merupakan event tahunan HATTI. Secara khusus perkenankan
Wakil Menteri
Bapak
kesediaan
atas
terima kasih dan penghargaan yang setinggi-tingginya
ini'
Tahunan
perhubungan dan PU L.tuungkan waktu untuk menghacliri Pertemuan Ilmiah
"Geotechnical Solution in
Hadirin yang saya hormati, dalam PIT kali ini diusung tema
and Mining
Indonesia to Responcl the Challenge of Urban, Industry Infiastructure
'l'ema ini diharapkan Japat mengantisipasi perkembangan yang makin pesat
Development".
Bagaimanapun'
dan dibutuhkan pada sektor iniiastruktur dan pertambangan di lndonesia'
dengan konstruksi
perkembangan kedepan akan membawa kita pada kebutuhan pembangunan
jernbatan dan terowongan. Untuk dapat rnewujudkan ini, bagaimanapun
,kulu b"ruiseperti
tidak dapat dihindari suatu tahap yang kritis dimana masalah-masalah geoteknik harus
solusi yang
diselesaikan terlebih dahulu. Para ahli geoteknik diharapkarr dapat memberikan
dapat
terbaik. Dalam kerangka inilah para ahli geoteknik dituntut untuk secara terus menerus
di
meningkatkan kompetensinya agar dapat mengikuti perkembangan dan kebutuhan
lapangan.
HATTI yang saya cintai, perkenankan saya untuk mengingatkan kembali bahwa
tahun 2015 tidak terasa semakin mendekat, dimana akan dimulai pasar bebas ASEAN. Mulai
para anggota
tahun tersebut, pekerjaan jasa konstruksi termasuk geoteknik akan dipasarkan secara bebas di
seluruh negara-negara ASEAN, artinya setiap orang atau badan usaha akan memiliki
kesempatan yang sama untuk memperebutkan lapangan pekerjaan geoteknik di negara-negara
ASEAN termasuk di Indonesia.
para anggota HATTI yang saya cintai, sungguh akan sangat ironis apabila pekerjaan
geoteknik di Indonesia justru dikerjakan oleh orang-orang bukan Indonesia. Adalah menjadi
iunggung jawab kita semua untuk mempertahankan eksistensi profesi geoteknik di Indonesia
sehingga mampu menjadi tuan rumah di negeri sendiri dan bukannya tamu di negeri sendiri.
Oleh karena itu marilah kita persiapkan diri kita masing-masing dalam menghadapi pasar
bebas ASEAN 2015 nanti.
Sebagai penutup, saya ucapkan banyak terima kasih atas kehadiran Bapak/lbu semua'
khususnya saya tujukan pada sponsor utama kali ini, GE,OHARBOUR, dan sponsor-sponsor
lainnla ).ang telah turut berpartisipasi sehingga PIT ini dapat berlangsung dan berakhir
denoan sukses dari mulai hari ini sampai besok. Selamat mengikuti PIT.
',\ :ss.rlamu'alaikum Wr. Wb.
i.',.::;:. I -l \or ember 2013
"
-
\"1:s.':.'rir Irslanr. \{SE.. Ph.D
I7'h
Annual Scientific Meeling
Jakarta, I 3-14 November
201 3
Agus Darmawan
11.
Adi
Analisa Mikrotremor dengan Metode HVSR (Horizontal to Vertical Spectral
Ratio) untuk Pemetaan Mikrozonasi di Kelurahan Kejawan Putih Tambak
Surabaya
Ria Asih Aryani Soemitro; Trihanyndio Rendy Satrya; Dwa Desa I4/arnana;
Reza Agus Parlindungan Harahap; Laily Endah Fatmawati
12.
Application of 25 m Height of MSE Wall for Road Widening
Rivai Sargawi; Endra Susila
13.
Research on Eartiquakes Induces Liquefaction in Padang and Yogyakarta
211-l1f
I I '-ll-l
Area
Agus SetyoMuntohar..
14.
Analisa Beban Gempa pada Dinding Besmen dengan Plaxis 2D
Gouw TL, Ferry Aryonto, Irpan
15. Clay Stabilisation
16.
vlll
With Stillage for Subgrade
Stabilisasi Tanah Lempung dengan Stillage untuk Lapisan DASAR TANAH
Ibrahirn, Muhammad Ar.fan
ll-r-:.xt
Different Types of Ground Source Heat Pump and its Usage.
GUNAIilA|V Anrhony ... ..
l+r-:::
I7'h Annual
Scientific Meeting
Jakarta, I3-11 November 20t3
4.
5.
Setianto Samingan Agus; Nicholas Mace
135-140
Studi Eksperintal Potensi Penggunaan BakteriBacillus Subtilis untuk
Meningkatkan Kuat Geser Tanah Pasir
Yustian Heri Suprapto; Wiwik Rahayu; Hussein Mroueh
141-146
Karakteristik Kimia, Fisis dan Mekanis Abu Sawit dalam Aplikasi
Geoteknik
Muhardi; Ferry Fatnanta; Rizqy Yuliana
147-152
Other Session
1.
2"
3.
4.
5"
6.
7.
8"
9"
10.
:
Application of Vacuum preloading Method in lndonesia
Yu Liu
I
Some New Ground Improvement Techniqr_res in China
Xiaoming Lou; Jihong Cu...
r59-r66
Perhitungan Praktis Perenca naan Pondasi Tiang Terhadap Beban Lateral
Hadi Rusjanto Tanuwidj ajct
167
53-l 58
-172
Sudut Keruntuhan Galian Vertikal dari Beberapa Skala pengamatan
Berbeda
Herman Wahvudi
173-178
Studi Parametrik Perilaku MSEW Dengan Material Granular Terhadap
Beban Dinarnik
William Y. Sormin; Widjojo A. Prakoso
l7g_lg4
Power Spectrum Density of wavelet (psDw) Technique for Determining
Attenuation Factor of Soil Structures.
Sri Atmaja P. Rosyidi
l g5_ I92
Korelasi Hasil Uji Mackintosh probe dengan Kuat Geser Undrained dari
pengujian Vane shear Lapangan
Soewignjo Agus l+tugroho; Ferry Fatnanta; Rizka Safitrt ... ......
t9i-198
studi Eksperimental Potensi Likuifaksi di Kali opak Imogiri Daerah
Istimewa Yogyakarta
Lindung Zalbuin Mase; Teuku Fai,sal Fathani; Agus Darmawan Atli
199_l0l
Liquefaction Potential Analysis on Bantul Regency and yogyakarta
Area
Bonifacius Adiguna Yogatama; Teuku Faisal Fathani,
105_210
cin
Identifikasi potensi likuifaksi tanah untuk penyiapan pengembansan lahan
VII
r,l
:
L'-i-r,r-iir? k
dkk-Institut Teknologi Bandung
67-72
K.-rnparasi vs30 Berdasarkan Metode Downhole Seismik dan Metode
\I.\S\\'
:.
Il'icliojo A. Prakoso; I Nyoman Sukanta; Damrizal Damoerin
13-76
Pengembangan Metode Zonifikasi Penggunaan PondasiDangkal untuk
Bangunan Sederhana Tahan Gempa
Ria Asih Aryani Soemitro; Trihanyndio Rendy Satrya; Dwa Desa Warnano;
Reza Agus Parlindungan Harahap
77 -84
Session
1
2.
3.
II
:
Impact of Wet-Dry Cycles to Shear Strength and Swelling Behavior in
Expansive Clay Using Artificial Soil
Yonathan Setiawan: Edwin Laurencis; Hasbullah Nowir........ .....
Individu Test Sistem Cakar Ayarn Modifikasi Pada Tanah Ekspansif Model
Skala Penuh di Lapangan
Bambang Setiawan; Hary Christady Hardiyatmo; Bambang Suhendro;
AEys Darmawan Adi...
.
2.
s
ar
i,
I'{ur
ly
G
oft,
Metode dan Prosedur Analisis Hitung Balik Pada Kasus Kelongsoran Lereng
R[vai Sargavti; Anton Junaidi
Session
I
101- I 08
Shear Strength and Long Term Compressibility of TropicalPeat
Yu I i n da
5,
9l-100
Bearing Capacity Improvement by Grid and Woven Bamboo Reinforcernent
Ratna Dewi; Yulindasari Sutejo; Hanafiah...
4.
85-90
III
109-l l4
1
l5-120
:
Perfonnance of Storage Tanks Supported on Deep Vibro Techniques
Leong Kam [4/eng; Hendy l'l/iyono; Giovanni Ahmad
121-t26
Experimental Study of Stabilization Expansive Clay Soils by Using
Electrokinetics Process
lrlahesson Hotmarama Panjaitan; Ahmad Rifu'I; Agus Darmawan Adi,'
P. Sumardi
127
Design and performance of a reclamation work in Singapore
-134
Annual Scientific Meeting
Jakarta. I3-14 November 201 3
I7'h
TABLE OF CONTEI.{TS
Preface Committee Chairman
Message from President of Indonesian Society for Geotechnical Engineering
(rsGE) ..................
Organizing Committee
Iil
Table of Contents
tv
Keynote Speakers
I
Innovative Soft Soil Improvement Method through Intelligent use
Vacuum De-Watering and Dynamic Compaction Techniques
Prof. Robert Y. Liang, Prof. Tuncer B. Edil
2
"
2'
3"
4.
5.
of
Methods of soft ground treatment and rigid bored pile foundation for
offshore structure.
Mr. Thomas Domanski / Regional Manager, BAUER southeast Asia pacific
9qssion
I
:
I
l-18
l9-34
:
The study of strip Footing Bearing capacity on Layered clay Soils Using
"Meyerhof and Hanna" Method and Finite Element Method (plaxis
Program)
Arief Budi Parsatya; Aswin Lim,. Siska Rustiani lrawan
35-41
Pengaruh Pre-Boring pada Kapasitas Friksi Tiang pancang
Bigman M Hutapea, Aksan Kawanda, Edwin Laurencis, Achmad Arifin,
Abdi Pasya, Bagaskara Kusuma
4l -50
Kapasitas cabut Jangkar Pelat Tipe Bintang pada Tanah Kohesiv
Abdul Rachman; Lawalenna Samang; A.M. Imran,.Achmad Bakri M..
5l-58
Estimasi Bearing Stratum untuk Desain pondasi riang dengan Menggunakan
Geostatistik
Ardy Arsyad, M. Ihdam, M. Iskandar ......
59-66
Pengembangan Peta Klasifikasi Tanah dan Kedalaman Bantuan Dasar untuk
Menunjang Pembuatan Peta Mikrozonsi Jakarta Dengan Mengsunakan
Mikrotremor Arrav.
l7'h Annual Scientific
.lakarla, I 3-l
I
Meeting
Novemher 20 I 3
Shear Strength and Long Term Compressibility of Tropical
Peat
Yulindasari Sutejor
'Dos"n Jurusan Teknik Sipil, Fakultas Teknik, Universitas Sriwiiaya
Jl. Raya Praburnulih KM 32 Indralaya, Sunratera Selatan, r-mail: [email protected]
Nurtv Gofar
2
'Dosen Jurusan Teknik Sipil, Fakultas Teknik, [Jniversitas lndo Global Mandiri, Jl. Jend. Sudirman,
No. 629, Km 4, Palembang, 30128, Sumatera Selatan, e-mail: nurrygof-ar@)rahoo.c'm
ABS'|RACT : Ahnost 1.5 million hectare (20.60 Yi) of South Sumatra is covered by peat overlaying soft
cohesive soil. Thus, the knowledge on the compression behavior of peat soil is essentfal fbr the aesfun of
infiastructures in the area. This paper discusses the shear strength and long tenn compression behavior of
preat" 'lhe sheal strength is assessed by field vane shear test ancl laboratory direct shear test while
the long
trerm eompression behavior is analyzed based on data obtained frorn consolidation test perforrned in Rowe
eell with excess pore water pressLrre measllrerlent. Study shorvs that the peat has very low shear strength
indicated by low cohesion while the high internal friction angle was derived from the flber content.
Fufthernore, the results indicate that the peat has a significant secondary compression stage which is not
rj;onstant with the logarithmic of tin"re. The secondary compressic,n stafied as early as 65 oh degree of primary
t,lrnsolidation. The consolidation test with pore water pressure measllrement using Rowe cell enables the
cbservation of the large deformation and better assessment olthe long term compression behavior of fibrous
peat"
Keyrvords: peal, shear strenglh, contpression behavior, pore-v)a,ier pressure mec.tsLrrement
ABSTRAK : Hampir
1.5 jLrta hektar (20.60%) luas
propinsi Surnatra Selatan ditutupi oleh tanah garnbut di
atas tanah lernpung lunak. Oleh karena itu pengetalruan mengenai sifat kompresibilitas tanah gambut sangat
periting bagi perencanaan infrastruktur di daerah ini. Artikel ini rnembahas kekuatan geser dan
k-r.rnrpnesibilitas tanalr garnbut. Kekuatan geser diukr-rr dengan uji geser baling di lapangan dan uji geser
iangsung
di
laboratorium, sedangkan kornpresibilitas dianalisis berdasarkan hasil pengujian koniolidasi
rnenggunakan sel Rowe dengan pengr:kuran tekanan pori. Hasil str-rdi menunjukkan bahwa tanah mempunyai
Isir-rn trl paniu-les. but also rhe plastic
f ielding of solid ntarerial t Sanrson and La
Rochell:. l9-l r. Sr,rti r.searr'hers including
ill
I 7'h Annual Scientifc Meet ing
Jakarta. I3-l4 November 20I3
Fox and Edil (1994) argued that the tertiary
compression can be neglected because it
generally started after the design life of
structures.
The time-compression curves derived from
results of one-dimensional consolidation test
on peat usually resemble the Type 2 curve
(Figure 2) in which the primary consolidation
is very rapid and secondary compression does
not vary linearly with logarithmic of time.
Therefore the qr-rantification of secondary
compression based on conventional
compression-logarithmic of time method
proposed by Cassagrande (1936) which was
later extended by Dhowian and Edil (1980)
fiequently under-estimates the settlement.
In some cases, the time compression curve
peat
of
follows Type 3 curve (Figure 2) where
no inflection point was identified, thus tlre end
of primary consolidation (tp) cannot
be
predicted by Cassagrande method.
Robinson (1999) pointed out that the end of
primary consolidation is actually the tirne
pressure curves was proposed by Robinson
(2003).
If the primary consolidation and secondary
compression were separated in the timecompression curve, the e-log p' curve can be
constructed for primary consolidation only
(Fox, 2003). The curve is required for the
determination of compression index (c") and
pre-consolidation pressure (cr'") of the soil.
The typical time-compression curve
obtained from consolidation test on soil used
in this study is shown in Figure 3. The shape
of the compression curve resembles the Type 2
curve (Figure 2) which is typical of
compression of peat soil. The shape of the
time-compression curve indicates that the
deformation process of the peat deviates from
the simple model used ir-r Terzaghi's
consolidation equation, which is the basis for
the Cassagrande and Taylor's evaluations of
primary consolidation and the estimation of
the coefficient of consolidation.
when full dissipation of excess pore water
pressure is achieved; thus, measurentent of
excess pore water pressure
-a/!-
durin-e
,i;
in:
bl
corrsolidation test is required. His observation
showed that the excess pore water pressure
dissipation is completed earlier than tlre tinre
t._Ad:
-
predicted from the inflection point of the
settlement curve. Further anall sis by
Robinson (2003) supported the argunrent made
by previous researchers that the secondary
compression of some soils actuallv stafis
Alog/
{r.
i/
/
tJ:
r a !tirr
I
r
,l*.rr",r*,_1,"n*.r,
during the dissipation of excess pore water
r{ir
ri'.,
3 Typical Time Compression Curve
pressure from the soil.
Figure
Terzaghi's one dimensional consolidation
theory stated that the compression during
primary consolidation is linearlr correlated
with the dissipation of excess pore water
pressure. Conversely, the actual cun e derived
from laboratory consolidation test on peat soil
was not actually follows a straight line because
the settlement was actually due to the
combination of excess pore water pressure
dissipation on primary consolidation and creep
or secondary compression. A method for
separating the primary consolidation and
secondary compression that occur- during the
Consolidation Test
compression, even though less
significant than the primary consolidation in
term of magnitude, could be very important in
term of the design life of a structure. The
secondary compression may have started
during the process of excess pore water
consolidation process based
pressure dissipation.
on
timecompression and the time-excess pore water
112
from
The curve indicates that the primary
is dominant in term of
consolidation
magnitude and the rate is high. The secondary
compression occurred at a slower rate and is
non-linear with logarithmic of time. This part
of the
Method suggested by Robinson is used in
evaluating the time compression curve in
Figure 3. The procedure is as follows:
I 7'h Annual Scientific Meeting
Jakarta, I3-ll November 201 3
L
]
l.
Plot the compression versus log time (in
minutes)
Plot the degree of consolidation U
o%
vs
log time, the time where at U reach
100Yo is the end of primary
i
Figure 4 shows that the compression index
(cc) for primary consolidation is 3.15 which
slightly lower than the slope evaluated based
on total settlement i.e 5.0.
consolidation (ttoo)
-1. Plot the compression versus degree of
-l
consolidation.
J. Draw a curve
and a straight line through
the points. The point where the curve
deviates from linearity is identified as
degree of consolidation where secondary
compression begin (Uo)
--i. Separate the primary consolidation curve
from the secondary compression
6. Evaluate cu and c. based on primary
consolidation curve only (Figure 4)
7. Evaluate 3o based on secondary
compression curve which stafi at tp
(Here the secondary compression curve
is drawn on linear or log scale in both
AXES.
The results of the analysis of
tirne
compression curve are presented in Table l.
The results indicate that cv decreases with
increasing consolidation pressllre. This
finding is in agreernent with the theory of
consolidation, which stated that the coefficient
cf rate of consolidation decreases with
increasing consolidation pressure (Leonards
and Girault, 1961). As shown in Figure 3, the
secondary compression index co is not
constant. However, the curve can be linearized
by plotting both d" and time in linear scale as
suggested by Robinson (2003). The linear
lbrm enables the determination of m value
which increases with increasing consolidation
pressure.
l. Compression Characteristics Obtained
from Robinson Procedure
Table
p'
ttoo
tp
27.67
25.83
23.50
23.00
G't"^
19.83 61.67 5.689
t7 .67 65.00 4.947
I 5.83 69.00 4.179
I 4.33 70.50 3.259
U
w' t^' ,^t", ca
25
!0
100
204
cr
nt :
0.0109
0.0124
0.0 t 57
0.021 I
o,".Jul3,*ru, looo
Figure 4: Typical e-Log p, Curve for
Determ ination of Compression Index
4. CONCLUSIONS
The peat used in this study is of fibrous
type. The undrained shear strength obtained
from field vane test is l0 kpa, while drained
shear strength measured by direct shear test is
c: 6.4 kPa and d':22o.It should be noted
that the high internal friction angle was
derived from fiber content and not reliable.
Evaluation of time settlement curve by
Robinson (2003) method indicates that the
secondary compression started as early as 65
Yo degree of consolidation. The beginning of
secondary compression (to) is l8 minutes
while the completion of primary consolidation
(t1ss) is 26 minutes. The primary compression
parameters c, : 3.5 while the coefficient of
rate of consolidation (c,,) obtained ranges from
5.69 to 3.26 for a range of pressure from 25 to
200 kPa. The secondary compression index zir
increases from 0.0102 to 0.0304 for
consolidation pressure of 25 to 200 kpa.
Consolidation test with pore water pressure
measurement is very useful for the evaluation
of compression behavior of peat. The
separation
of primary and
secondan.
consolidations is very impoftant for the
evaluation of long term contpressibilitl,
behavior of peat because the conventional
evaluation of settlement based on the timecompression curve ma), result in o\ erprediction of prirnary consolidation and underprediction of secondan consolidation.
ll3
I 7'h Annual Scientifc Meeting
Jakarta, l3-14 November 2013
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British Standards Institution.l 981 . Methods of Test for
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Fox, P. J., Edil, T. B. and Lan, L. T. 1992. colc" Concept
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Gofar N and Sutejo, Y. 2007. Long
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Head, K. H. 1982. Manual of Soil Laboratory Testing,
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and
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Huat, B. B. K. 2004. Organic and Peat Soil Engineering.
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Macfarlane, I. C. 1969. Engineering Characteristics of
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R. G.
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Coefficient of Consolidation by the Inflection Point
Method, Geotechnique , 47 (5): 1 079- I 08 I .
Robinson, R. G. 1999. Consolidation Analysis with
Pore Pressure Measurements. Geotechnique, 49(1):
127-t32.
Robinson, R. G. 2003. A Study on the Beginning of
Secondary Compression of Soils. Journal of Testing
and Evaluation, 31(5):
l-l
0.
L. and La Rochelle, P.
19'72. Design and
Performance of an Expressway Constructed Over
Peat by Preloading. Canadian Geotechnical Journal,
Samson,
9:447-466.
t1+
HIMPUNAhI AHLI TEKNIK TANAH INDONESIA
INDOtIESIAN SO(;lETY FOR GEOTECHNICAL ENGINEERING (ISGE)
MEMBER SOCIEY OF INTERNAT]ONAL SOCIETY FOR SOIL MECHANICS
AND GEOTECHNTCAL ENGTNEERTNG {TSSMGE}
SffiArewwMWMw36W
KGeotechnical Solution in Indonesia to Respond
the Challenge of Urbano Industry,
Infrastructure and Mining Developmentn'
IF{
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Proceedin g
l7'' Annual Scientific Meeting
Jakarta, l3-14 November 2013
('Geotechnical
Solution in Indonesia to Respond
the Challenge of Urban, fndustry,
Infrastructure and Mining Developmenttt
Editor
:
Hasbullah Nawir
Bigman Marihat Hutapea
YP. Chandra
Widjojo Adhi Prakoso
Hendra Jitno
Agus Setyo Muntohar
HIMPUNAN AHLI TEKNIK TANAH INDONESIA
INDONESIAN SOCIETY FOR GEOTECHNICAL ENGINEERING (ISGE)
Basement Aldevco Octagon, Jl. Warung Jati Barat Raya No. 75
Jakarta Selatan 12740
I7tt' Annual Scientifc Meeting
Jakarta. I 3-11 November 201 3
KATA PENGANTAR
Assalamulaikum Wr. Wb.
Para undangan, para pengurus Pusat dan Daerah Himpunan Ahli Teknik Tanah Indonesia.
para pembicara dan peserta Pertemuan Ilmiah Tahunan HATTI yang kami hormati,
Pertemuan llmiah HATTI tahun ini mengambil tema .6Geotechnical Solution in Indonesia
to Respond the Challenge of Urban, Industry, Infrastructure and Mining Development".
Saat ini pemerintah dan swasta semakin giat melakukan investasi pada sektor konstruksi, baik
untuk bangunan pekantoran, apartemen, MRT, pelabuhan, jalan bebas hambatan maupun
inlrastruktur untuk perlambangan. Hal ini berhubungan dengan program pemerintah clalam
konteks percepatan pembangunan ekonomi Indonesia. Terobosan baru dalam meniawab
masalah geoteknik berkembang semakin pesat dan menjadikan keterlibatan serta peran
Geotechnical Engineers semakin penting.
Selain mengangkat topik seminar yang berkaitan dengan aspek geoteknik dan perkembangan
riset serta teknologi terbaru sebagai pendukungnya, PIT XVII inijuga menggelar Workshop
GROUND IMPROVEMENT FOR DIFFICULT SUBSOIL CONDITIoNS.
Kegiatan seminar dan workshop ini diharapkan dapat memberi kesempatan kepada seluruh
peserta untuk berbagi informasi dengan para praktisi konstruksi khususnya di bidane
SAtu haTi tentang
geoteknik.
Fada kesempatan ini, atas nama seluruh anggota panitia penyelenggara, kami meneucapkan
terima kasih kepada GEOHARBOUR GROUP sebagai sponsor utama seminar dan trrirksht p
Fertemuan
Ilmiah HATTI tahun 2013. Ucapan terimakasih juga kepada para pembicara.
penulis makalah, para sponsor dan para peserta yang telah berpartisipasi untuk suksesn\a
PIT-XVII ini. Kami mohon maaf apabila dalam penyelenggaraan pertemLran ini eJa
kekurangan yang tidak berkenan.
Selamat berdiskusi dan semoga Pertemuan Ilmiah Tahunan
perkembangan profesi Geoteknik di tanah air.
Wassalamualaikum Wr Wb,
Panitia PIT - XVII
Dr. Ir. Wiwit nanayu
Ketua
ini dapat bermant-aat
basi
Annual Scienti/ic Nleeling
Jckarta, I 3-11 November 2013
l7'1'
SAMBUTAN KETUA UMUM
Assalamu'alaikurn Wr. Wb.
Salam Sejahtera bagi kita semua'
pembicara, dan saudara-saudara
Bapak wakil Menteri, Bapak Dirjen, para undangan, para
hormati, atas nama Pengurus
saya
peserta Peftemuan llmiah Tahunan XVII HATTI.yang
pusat HATl'l saya ucapkan terima kasih atas kedatangan Bapak/lbu sekalian di acara ini'
saya menyampaikan
yang merupakan event tahunan HATTI. Secara khusus perkenankan
Wakil Menteri
Bapak
kesediaan
atas
terima kasih dan penghargaan yang setinggi-tingginya
ini'
Tahunan
perhubungan dan PU L.tuungkan waktu untuk menghacliri Pertemuan Ilmiah
"Geotechnical Solution in
Hadirin yang saya hormati, dalam PIT kali ini diusung tema
and Mining
Indonesia to Responcl the Challenge of Urban, Industry Infiastructure
'l'ema ini diharapkan Japat mengantisipasi perkembangan yang makin pesat
Development".
Bagaimanapun'
dan dibutuhkan pada sektor iniiastruktur dan pertambangan di lndonesia'
dengan konstruksi
perkembangan kedepan akan membawa kita pada kebutuhan pembangunan
jernbatan dan terowongan. Untuk dapat rnewujudkan ini, bagaimanapun
,kulu b"ruiseperti
tidak dapat dihindari suatu tahap yang kritis dimana masalah-masalah geoteknik harus
solusi yang
diselesaikan terlebih dahulu. Para ahli geoteknik diharapkarr dapat memberikan
dapat
terbaik. Dalam kerangka inilah para ahli geoteknik dituntut untuk secara terus menerus
di
meningkatkan kompetensinya agar dapat mengikuti perkembangan dan kebutuhan
lapangan.
HATTI yang saya cintai, perkenankan saya untuk mengingatkan kembali bahwa
tahun 2015 tidak terasa semakin mendekat, dimana akan dimulai pasar bebas ASEAN. Mulai
para anggota
tahun tersebut, pekerjaan jasa konstruksi termasuk geoteknik akan dipasarkan secara bebas di
seluruh negara-negara ASEAN, artinya setiap orang atau badan usaha akan memiliki
kesempatan yang sama untuk memperebutkan lapangan pekerjaan geoteknik di negara-negara
ASEAN termasuk di Indonesia.
para anggota HATTI yang saya cintai, sungguh akan sangat ironis apabila pekerjaan
geoteknik di Indonesia justru dikerjakan oleh orang-orang bukan Indonesia. Adalah menjadi
iunggung jawab kita semua untuk mempertahankan eksistensi profesi geoteknik di Indonesia
sehingga mampu menjadi tuan rumah di negeri sendiri dan bukannya tamu di negeri sendiri.
Oleh karena itu marilah kita persiapkan diri kita masing-masing dalam menghadapi pasar
bebas ASEAN 2015 nanti.
Sebagai penutup, saya ucapkan banyak terima kasih atas kehadiran Bapak/lbu semua'
khususnya saya tujukan pada sponsor utama kali ini, GE,OHARBOUR, dan sponsor-sponsor
lainnla ).ang telah turut berpartisipasi sehingga PIT ini dapat berlangsung dan berakhir
denoan sukses dari mulai hari ini sampai besok. Selamat mengikuti PIT.
',\ :ss.rlamu'alaikum Wr. Wb.
i.',.::;:. I -l \or ember 2013
"
-
\"1:s.':.'rir Irslanr. \{SE.. Ph.D
I7'h
Annual Scientific Meeling
Jakarta, I 3-14 November
201 3
Agus Darmawan
11.
Adi
Analisa Mikrotremor dengan Metode HVSR (Horizontal to Vertical Spectral
Ratio) untuk Pemetaan Mikrozonasi di Kelurahan Kejawan Putih Tambak
Surabaya
Ria Asih Aryani Soemitro; Trihanyndio Rendy Satrya; Dwa Desa I4/arnana;
Reza Agus Parlindungan Harahap; Laily Endah Fatmawati
12.
Application of 25 m Height of MSE Wall for Road Widening
Rivai Sargawi; Endra Susila
13.
Research on Eartiquakes Induces Liquefaction in Padang and Yogyakarta
211-l1f
I I '-ll-l
Area
Agus SetyoMuntohar..
14.
Analisa Beban Gempa pada Dinding Besmen dengan Plaxis 2D
Gouw TL, Ferry Aryonto, Irpan
15. Clay Stabilisation
16.
vlll
With Stillage for Subgrade
Stabilisasi Tanah Lempung dengan Stillage untuk Lapisan DASAR TANAH
Ibrahirn, Muhammad Ar.fan
ll-r-:.xt
Different Types of Ground Source Heat Pump and its Usage.
GUNAIilA|V Anrhony ... ..
l+r-:::
I7'h Annual
Scientific Meeting
Jakarta, I3-11 November 20t3
4.
5.
Setianto Samingan Agus; Nicholas Mace
135-140
Studi Eksperintal Potensi Penggunaan BakteriBacillus Subtilis untuk
Meningkatkan Kuat Geser Tanah Pasir
Yustian Heri Suprapto; Wiwik Rahayu; Hussein Mroueh
141-146
Karakteristik Kimia, Fisis dan Mekanis Abu Sawit dalam Aplikasi
Geoteknik
Muhardi; Ferry Fatnanta; Rizqy Yuliana
147-152
Other Session
1.
2"
3.
4.
5"
6.
7.
8"
9"
10.
:
Application of Vacuum preloading Method in lndonesia
Yu Liu
I
Some New Ground Improvement Techniqr_res in China
Xiaoming Lou; Jihong Cu...
r59-r66
Perhitungan Praktis Perenca naan Pondasi Tiang Terhadap Beban Lateral
Hadi Rusjanto Tanuwidj ajct
167
53-l 58
-172
Sudut Keruntuhan Galian Vertikal dari Beberapa Skala pengamatan
Berbeda
Herman Wahvudi
173-178
Studi Parametrik Perilaku MSEW Dengan Material Granular Terhadap
Beban Dinarnik
William Y. Sormin; Widjojo A. Prakoso
l7g_lg4
Power Spectrum Density of wavelet (psDw) Technique for Determining
Attenuation Factor of Soil Structures.
Sri Atmaja P. Rosyidi
l g5_ I92
Korelasi Hasil Uji Mackintosh probe dengan Kuat Geser Undrained dari
pengujian Vane shear Lapangan
Soewignjo Agus l+tugroho; Ferry Fatnanta; Rizka Safitrt ... ......
t9i-198
studi Eksperimental Potensi Likuifaksi di Kali opak Imogiri Daerah
Istimewa Yogyakarta
Lindung Zalbuin Mase; Teuku Fai,sal Fathani; Agus Darmawan Atli
199_l0l
Liquefaction Potential Analysis on Bantul Regency and yogyakarta
Area
Bonifacius Adiguna Yogatama; Teuku Faisal Fathani,
105_210
cin
Identifikasi potensi likuifaksi tanah untuk penyiapan pengembansan lahan
VII
r,l
:
L'-i-r,r-iir? k
dkk-Institut Teknologi Bandung
67-72
K.-rnparasi vs30 Berdasarkan Metode Downhole Seismik dan Metode
\I.\S\\'
:.
Il'icliojo A. Prakoso; I Nyoman Sukanta; Damrizal Damoerin
13-76
Pengembangan Metode Zonifikasi Penggunaan PondasiDangkal untuk
Bangunan Sederhana Tahan Gempa
Ria Asih Aryani Soemitro; Trihanyndio Rendy Satrya; Dwa Desa Warnano;
Reza Agus Parlindungan Harahap
77 -84
Session
1
2.
3.
II
:
Impact of Wet-Dry Cycles to Shear Strength and Swelling Behavior in
Expansive Clay Using Artificial Soil
Yonathan Setiawan: Edwin Laurencis; Hasbullah Nowir........ .....
Individu Test Sistem Cakar Ayarn Modifikasi Pada Tanah Ekspansif Model
Skala Penuh di Lapangan
Bambang Setiawan; Hary Christady Hardiyatmo; Bambang Suhendro;
AEys Darmawan Adi...
.
2.
s
ar
i,
I'{ur
ly
G
oft,
Metode dan Prosedur Analisis Hitung Balik Pada Kasus Kelongsoran Lereng
R[vai Sargavti; Anton Junaidi
Session
I
101- I 08
Shear Strength and Long Term Compressibility of TropicalPeat
Yu I i n da
5,
9l-100
Bearing Capacity Improvement by Grid and Woven Bamboo Reinforcernent
Ratna Dewi; Yulindasari Sutejo; Hanafiah...
4.
85-90
III
109-l l4
1
l5-120
:
Perfonnance of Storage Tanks Supported on Deep Vibro Techniques
Leong Kam [4/eng; Hendy l'l/iyono; Giovanni Ahmad
121-t26
Experimental Study of Stabilization Expansive Clay Soils by Using
Electrokinetics Process
lrlahesson Hotmarama Panjaitan; Ahmad Rifu'I; Agus Darmawan Adi,'
P. Sumardi
127
Design and performance of a reclamation work in Singapore
-134
Annual Scientific Meeting
Jakarta. I3-14 November 201 3
I7'h
TABLE OF CONTEI.{TS
Preface Committee Chairman
Message from President of Indonesian Society for Geotechnical Engineering
(rsGE) ..................
Organizing Committee
Iil
Table of Contents
tv
Keynote Speakers
I
Innovative Soft Soil Improvement Method through Intelligent use
Vacuum De-Watering and Dynamic Compaction Techniques
Prof. Robert Y. Liang, Prof. Tuncer B. Edil
2
"
2'
3"
4.
5.
of
Methods of soft ground treatment and rigid bored pile foundation for
offshore structure.
Mr. Thomas Domanski / Regional Manager, BAUER southeast Asia pacific
9qssion
I
:
I
l-18
l9-34
:
The study of strip Footing Bearing capacity on Layered clay Soils Using
"Meyerhof and Hanna" Method and Finite Element Method (plaxis
Program)
Arief Budi Parsatya; Aswin Lim,. Siska Rustiani lrawan
35-41
Pengaruh Pre-Boring pada Kapasitas Friksi Tiang pancang
Bigman M Hutapea, Aksan Kawanda, Edwin Laurencis, Achmad Arifin,
Abdi Pasya, Bagaskara Kusuma
4l -50
Kapasitas cabut Jangkar Pelat Tipe Bintang pada Tanah Kohesiv
Abdul Rachman; Lawalenna Samang; A.M. Imran,.Achmad Bakri M..
5l-58
Estimasi Bearing Stratum untuk Desain pondasi riang dengan Menggunakan
Geostatistik
Ardy Arsyad, M. Ihdam, M. Iskandar ......
59-66
Pengembangan Peta Klasifikasi Tanah dan Kedalaman Bantuan Dasar untuk
Menunjang Pembuatan Peta Mikrozonsi Jakarta Dengan Mengsunakan
Mikrotremor Arrav.
l7'h Annual Scientific
.lakarla, I 3-l
I
Meeting
Novemher 20 I 3
Shear Strength and Long Term Compressibility of Tropical
Peat
Yulindasari Sutejor
'Dos"n Jurusan Teknik Sipil, Fakultas Teknik, Universitas Sriwiiaya
Jl. Raya Praburnulih KM 32 Indralaya, Sunratera Selatan, r-mail: [email protected]
Nurtv Gofar
2
'Dosen Jurusan Teknik Sipil, Fakultas Teknik, [Jniversitas lndo Global Mandiri, Jl. Jend. Sudirman,
No. 629, Km 4, Palembang, 30128, Sumatera Selatan, e-mail: nurrygof-ar@)rahoo.c'm
ABS'|RACT : Ahnost 1.5 million hectare (20.60 Yi) of South Sumatra is covered by peat overlaying soft
cohesive soil. Thus, the knowledge on the compression behavior of peat soil is essentfal fbr the aesfun of
infiastructures in the area. This paper discusses the shear strength and long tenn compression behavior of
preat" 'lhe sheal strength is assessed by field vane shear test ancl laboratory direct shear test while
the long
trerm eompression behavior is analyzed based on data obtained frorn consolidation test perforrned in Rowe
eell with excess pore water pressLrre measllrerlent. Study shorvs that the peat has very low shear strength
indicated by low cohesion while the high internal friction angle was derived from the flber content.
Fufthernore, the results indicate that the peat has a significant secondary compression stage which is not
rj;onstant with the logarithmic of tin"re. The secondary compressic,n stafied as early as 65 oh degree of primary
t,lrnsolidation. The consolidation test with pore water pressure measllrement using Rowe cell enables the
cbservation of the large deformation and better assessment olthe long term compression behavior of fibrous
peat"
Keyrvords: peal, shear strenglh, contpression behavior, pore-v)a,ier pressure mec.tsLrrement
ABSTRAK : Hampir
1.5 jLrta hektar (20.60%) luas
propinsi Surnatra Selatan ditutupi oleh tanah garnbut di
atas tanah lernpung lunak. Oleh karena itu pengetalruan mengenai sifat kompresibilitas tanah gambut sangat
periting bagi perencanaan infrastruktur di daerah ini. Artikel ini rnembahas kekuatan geser dan
k-r.rnrpnesibilitas tanalr garnbut. Kekuatan geser diukr-rr dengan uji geser baling di lapangan dan uji geser
iangsung
di
laboratorium, sedangkan kornpresibilitas dianalisis berdasarkan hasil pengujian koniolidasi
rnenggunakan sel Rowe dengan pengr:kuran tekanan pori. Hasil str-rdi menunjukkan bahwa tanah mempunyai
Isir-rn trl paniu-les. but also rhe plastic
f ielding of solid ntarerial t Sanrson and La
Rochell:. l9-l r. Sr,rti r.searr'hers including
ill
I 7'h Annual Scientifc Meet ing
Jakarta. I3-l4 November 20I3
Fox and Edil (1994) argued that the tertiary
compression can be neglected because it
generally started after the design life of
structures.
The time-compression curves derived from
results of one-dimensional consolidation test
on peat usually resemble the Type 2 curve
(Figure 2) in which the primary consolidation
is very rapid and secondary compression does
not vary linearly with logarithmic of time.
Therefore the qr-rantification of secondary
compression based on conventional
compression-logarithmic of time method
proposed by Cassagrande (1936) which was
later extended by Dhowian and Edil (1980)
fiequently under-estimates the settlement.
In some cases, the time compression curve
peat
of
follows Type 3 curve (Figure 2) where
no inflection point was identified, thus tlre end
of primary consolidation (tp) cannot
be
predicted by Cassagrande method.
Robinson (1999) pointed out that the end of
primary consolidation is actually the tirne
pressure curves was proposed by Robinson
(2003).
If the primary consolidation and secondary
compression were separated in the timecompression curve, the e-log p' curve can be
constructed for primary consolidation only
(Fox, 2003). The curve is required for the
determination of compression index (c") and
pre-consolidation pressure (cr'") of the soil.
The typical time-compression curve
obtained from consolidation test on soil used
in this study is shown in Figure 3. The shape
of the compression curve resembles the Type 2
curve (Figure 2) which is typical of
compression of peat soil. The shape of the
time-compression curve indicates that the
deformation process of the peat deviates from
the simple model used ir-r Terzaghi's
consolidation equation, which is the basis for
the Cassagrande and Taylor's evaluations of
primary consolidation and the estimation of
the coefficient of consolidation.
when full dissipation of excess pore water
pressure is achieved; thus, measurentent of
excess pore water pressure
-a/!-
durin-e
,i;
in:
bl
corrsolidation test is required. His observation
showed that the excess pore water pressure
dissipation is completed earlier than tlre tinre
t._Ad:
-
predicted from the inflection point of the
settlement curve. Further anall sis by
Robinson (2003) supported the argunrent made
by previous researchers that the secondary
compression of some soils actuallv stafis
Alog/
{r.
i/
/
tJ:
r a !tirr
I
r
,l*.rr",r*,_1,"n*.r,
during the dissipation of excess pore water
r{ir
ri'.,
3 Typical Time Compression Curve
pressure from the soil.
Figure
Terzaghi's one dimensional consolidation
theory stated that the compression during
primary consolidation is linearlr correlated
with the dissipation of excess pore water
pressure. Conversely, the actual cun e derived
from laboratory consolidation test on peat soil
was not actually follows a straight line because
the settlement was actually due to the
combination of excess pore water pressure
dissipation on primary consolidation and creep
or secondary compression. A method for
separating the primary consolidation and
secondary compression that occur- during the
Consolidation Test
compression, even though less
significant than the primary consolidation in
term of magnitude, could be very important in
term of the design life of a structure. The
secondary compression may have started
during the process of excess pore water
consolidation process based
pressure dissipation.
on
timecompression and the time-excess pore water
112
from
The curve indicates that the primary
is dominant in term of
consolidation
magnitude and the rate is high. The secondary
compression occurred at a slower rate and is
non-linear with logarithmic of time. This part
of the
Method suggested by Robinson is used in
evaluating the time compression curve in
Figure 3. The procedure is as follows:
I 7'h Annual Scientific Meeting
Jakarta, I3-ll November 201 3
L
]
l.
Plot the compression versus log time (in
minutes)
Plot the degree of consolidation U
o%
vs
log time, the time where at U reach
100Yo is the end of primary
i
Figure 4 shows that the compression index
(cc) for primary consolidation is 3.15 which
slightly lower than the slope evaluated based
on total settlement i.e 5.0.
consolidation (ttoo)
-1. Plot the compression versus degree of
-l
consolidation.
J. Draw a curve
and a straight line through
the points. The point where the curve
deviates from linearity is identified as
degree of consolidation where secondary
compression begin (Uo)
--i. Separate the primary consolidation curve
from the secondary compression
6. Evaluate cu and c. based on primary
consolidation curve only (Figure 4)
7. Evaluate 3o based on secondary
compression curve which stafi at tp
(Here the secondary compression curve
is drawn on linear or log scale in both
AXES.
The results of the analysis of
tirne
compression curve are presented in Table l.
The results indicate that cv decreases with
increasing consolidation pressllre. This
finding is in agreernent with the theory of
consolidation, which stated that the coefficient
cf rate of consolidation decreases with
increasing consolidation pressure (Leonards
and Girault, 1961). As shown in Figure 3, the
secondary compression index co is not
constant. However, the curve can be linearized
by plotting both d" and time in linear scale as
suggested by Robinson (2003). The linear
lbrm enables the determination of m value
which increases with increasing consolidation
pressure.
l. Compression Characteristics Obtained
from Robinson Procedure
Table
p'
ttoo
tp
27.67
25.83
23.50
23.00
G't"^
19.83 61.67 5.689
t7 .67 65.00 4.947
I 5.83 69.00 4.179
I 4.33 70.50 3.259
U
w' t^' ,^t", ca
25
!0
100
204
cr
nt :
0.0109
0.0124
0.0 t 57
0.021 I
o,".Jul3,*ru, looo
Figure 4: Typical e-Log p, Curve for
Determ ination of Compression Index
4. CONCLUSIONS
The peat used in this study is of fibrous
type. The undrained shear strength obtained
from field vane test is l0 kpa, while drained
shear strength measured by direct shear test is
c: 6.4 kPa and d':22o.It should be noted
that the high internal friction angle was
derived from fiber content and not reliable.
Evaluation of time settlement curve by
Robinson (2003) method indicates that the
secondary compression started as early as 65
Yo degree of consolidation. The beginning of
secondary compression (to) is l8 minutes
while the completion of primary consolidation
(t1ss) is 26 minutes. The primary compression
parameters c, : 3.5 while the coefficient of
rate of consolidation (c,,) obtained ranges from
5.69 to 3.26 for a range of pressure from 25 to
200 kPa. The secondary compression index zir
increases from 0.0102 to 0.0304 for
consolidation pressure of 25 to 200 kpa.
Consolidation test with pore water pressure
measurement is very useful for the evaluation
of compression behavior of peat. The
separation
of primary and
secondan.
consolidations is very impoftant for the
evaluation of long term contpressibilitl,
behavior of peat because the conventional
evaluation of settlement based on the timecompression curve ma), result in o\ erprediction of prirnary consolidation and underprediction of secondan consolidation.
ll3
I 7'h Annual Scientifc Meeting
Jakarta, l3-14 November 2013
REFERENCES
Annual Book of ASTM Standards vol. 04.08 and 04.09.
1994.
British Standards Institution.l 981 . Methods of Test for
Soils for Civil Eng. Purposes. London, BS 1377Culloch FM. 2006. Guidelines for the Risk Management
of Peat Slips on the Construction of Low Volume/
Low Cost Road Over Peat. Scotland: For. Civ. Eng.
For. Comm.. pp. l-46.
Fox, P. J., Edil, T. B. and Lan, L. T. 1992. colc" Concept
applied to Compression of Peat. Joumal of Geotech
Eng, ASCE, I l 8(8): 1256-1263.
Fox, P. J.2003, Consolidation and Settlement AnalysisThe Civil Eng. Handbook 2 Chen, W.F. and Liew,
J.Y.R. Eds. Washington, D.C.
Gofar N and Sutejo, Y. 2007. Long
Term
Compressibility of Fibrous Peat. Malaysian Journal
of Civil Engineering. 19 t2) 101-116.
Holtz, R. D. and Kovacs, W. D. (1981) An Introduction
to Geotechnical Engineering. Prentice-Hall, Inc.,
Englewood Cliffs, New Jersey.
Head, K. H. 1982. Manual of Soil Laboratory Testing,
Vol 2:
Permeability, Shear Strength
and
Cornpressibility Tests. London: Pentech Press Ltd.
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