Articles

Found 8 Documents
Search

EFEKTIVITAS MODEL PEMBELAJARAN GROUP INVESTIGATION BENTUK CO-OP CO-OP TERHADAP PENINGKATAN HASIL BELAJAR SISWA SMA Rifa’i, Ahmad; Khosmas, F.Y.; Basri, M.
Jurnal Pendidikan dan Pembelajaran Vol 2, No 9 (2013): September 2013
Publisher : Jurnal Pendidikan dan Pembelajaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1777.419 KB)

Abstract

Abstract: This study aims to determine the learning outcomes of the learning model group investigation form a co-op co-op and conventional learning models of class X at SMA Kemala Bhayangkari Kubu Raya and to determine the effectiveness of the learning model group investigation form a co-op co-op compared with conventional learning models. The research method used was a quasi-experimental research design with a post-test only control design. The study sample XF grade (grade control) and XG-class (eksperiment class). The average post-test score results of experimental class 66,67 and control class 48,18 . Students who complete the experimental class numbered 22 people (56.41%) and the control class 5 students (15.15%). So the learning model group investigation form a co-op co-op is more effective than conventional learning models. Effect size of 1.17 is obtained. Finally, based on the applicable criteria, effect size in value is included in the high category. Keywords: Group investigation form a co-op co-op, Conventional   Abstrak: Penelitian ini bertujuan untuk mengetahui hasil belajar dengan model pembelajaran group investigation bentuk co-op co-op dan model pembelajaran konvensional siswa kelas X pada SMA Kemala Bhayangkari Kubu Raya dan untuk mengetahui efektivitas model pembelajaran group investigation bentuk co-op co-op dibandingkan dengan model pembelajaran konvensional. Metode penelitian yang digunakan adalah eksperimen semu dengan rancangan penelitian post-test only control design. Sampel Penelitian ini kelas X F (kelas kontrol) dan kelas X G (kelas ekspeimen). Rata-rata hasil nilai post-test kelas eksperimen 66,67 dan kelas kontrol 48,18. Siswa yang tuntas kelas eksperimen berjumlah 22 orang (56,41%) dan kelas kontrol 5 orang siswa (15,15%). Jadi model pembelajaran group investigation bentuk co-op co-op lebih efektif daripada model pembelajaran konvensional. Effect size diperoleh sebesar 1,17. Maka berdasarkan kriteria yang berlaku nilai effect size termasuk dalam kategori tinggi. Kata Kunci: Group investigation bentuk co-op co-op, Konvensional
PENENTUAN SIFAT TEKNIS TANAH JENUH SEBAGIAN DAN ANALISIS DEFORMASI LERENG AKIBAT PENGARUH VARIASI HUJAN PRAMUSANDI, Sony; RIFA’I, Ahmad; SURYOLELONO, Kabul Basah
Poli-Teknologi Vol 10, No 1 (2011)
Publisher : Politeknik Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Abstract Recently, landslides often occurs in natural slope in Indonesia, which is associated with the coming rainy season . The increment of ground water level cause by rainfall is affected the properties and behavior of soil especially the unsaturated soil. Generally, the stability of slope is evaluated based on safety factor, but the deformation occured at the soil can also be a good interest in assesing the stability of slope. This research is focused to observe the change of pore water pressure and ascoociate deformation considering the hydro-mechanical properties of unsaturated soil due to the effect of varies rainfall. In this research, numerical simulation was carried out to analysis the deformation of the slope affected by pore water pressure change due to rainfall using software-based Finite Element Method of SIGMA/W and SEEP/W from GEO-SLOPE 2004. Unsaturated soil properties, such as Soil Water Characteristic Curve (SWCC) and Hydraulic Conductivity function are obtained from laboratory test and also predicted based on grain-size distribution using psycho-empirical method in SOILVISION Database. HAVARA is used to help rainfall data analysis using statistic approach. Rainfall model is used to vary the moisture content to model unsaturated soil condition. There are six rainfall models, consists of one steady state model and followed by five transient model to accomodate the pore water pressure changes due to rainfall. The results show that rainfall with intensity near saturated permeability of soil gives more significant influence in increasing pore water pressure and deformation than normal rainfall even with long duration. Proposed countermeasure by providing counterweight and subdrain do not significantly effect the deformation, but it could improves the safety factor significantly, so that the slope is more in stable condition. Keywords : landslide, unsaturated soil properties, pore water pressure, slope deformation, numerical simulation, finite element method, countermeasures.
EVALUATION OF SOIL EMBANKMENT MASS MOVEMENT BY USING SUBDRAIN SYSTEM AND REINFORCEMENT BASED ON THE NUMERICAL SIMULATION OF SEMARANG-SOLO TOLL ROAD Dayanun, Syahbudin; Rifa’i, Ahmad; Suryolelono, Kabul Basah
Journal of the Civil Engineering Forum VOLUME: XXIII/1 - JANUARY 2014
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, UGM

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jcef.18898

Abstract

Semarang-Solo highway is a part of Trans Java Toll Road System, which in construction stage has soil embankment mass movement between Sta. 5+ 500, -5+800 part II Gedawang-Penggaron. In this case, research is conducted to again effective and efficient solution. The research object is soil embankment which moved on site. The research aim is to identify the cause of soil embankment mass movement, to know the effect of sub drain system to soil movement and also to provide alternative solution. Slope stability analysis was solved by Plaxis, based on topography, investigation data and field instrumentation after gain the validation result with accuracy of soil movement on horizontal direction of the slope, continued by simulation with variants model which affected by strength, loading combination (traffic load), water level (dry and raining season), sub drain system and earthquake. Horizontal movement result of simulation can be seen in location of inclinometer 4.The research result shown that soil movement pattern which strengthened with bored pile is sliding combination type of translation and rotation. The strengthened soil embankment mass with bored pile apparently still has movement as 0,246 m with SF 1,448. Due to traffic load, horizontal movement is 0,322 m with SF 1,368 where water level located in 5,5 m at BM 10 and 3,5 m at BM 11 and sub drain is pointed in 4 m mean depth. When rainy season the horizontal movement increase 0,324 m with SF 1,321 while in dry season become 0,320 m with SF 1,479. When sub drain existing reduce in average 2,0 m so horizontal movement also decrease as 0,254 m with SF 1,465. Earthquake simulation shown maximum horizontal movement is 1,422 m with SF 1,193. As alternative to minimize horizontal movement which cause by earthquake can be solved by reduce embankment height from 25,72 m to 20,72 m, simulation result provide horizontal deformation as 0,703 m with SF 1,567. In hence the existence of sub drain construction able to reduce horizontal movement of soil embankment mass in which increase the safety factor, reduction of embankment height also show positive impact and significant to horizontal movement due to earthquake.Keyword : soil mass movement, Plaxis program, sub drain system
ANALISIS STABILITAS FONDASI MESIN PEMBANGKIT HYDRO PADA SUNGAI BAWAH TANAH ZONA KARST Sulha, Sulha; Rifa’i, Ahmad; Sarita, Umran
DINAMIKA – Jurnal Ilmiah Teknik Mesin Vol 7, No 1 (2015)
Publisher : HALUOLEO UNIVERSITY

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1992.912 KB)

Abstract

Penelitian ini bertujuan untuk menganalisis stabilitas fondasi mesin pembangkit listrik hydro pada sungai bawah tanah zona karst di Goa Seropan, menggunakan metode elemen hingga model  plan-strain. Pendekatan analisis dilakukan pada tampang fondasi dengan menggunakan 4 model geometri. Material properti di lokasi konstruksi diambil dari hasil penelitian dan uji laboratorium IWRM Goa Seropan dari tim teknis UGM. Input gemoteri diperoleh dari data pengukuran lapangan yang disederhanakan, sedangkan input parameter tanah, batuan dan beton diperoleh dari data sekunder. Analisis model yakni beban statis dan dinamis menggunakan software PLAXIS  v8.2, yang divalidasi berdasarkan perhitungan manual. Hasil simulasi numeris menunjukkan penambahan bored pile 0,20 meter pada sistem fondasi pembangkit hydro-power mampu melawan tegangan yang terjadi di tanah dasar akibat beban gempa dengan faktor aman sebesar 2,01. Sistem fondasi pada model geometri I, dengan dimensi pelat horisontal sebesar 0,40 meter, dinding vertikal sebesar 0,30 meter, dan bored pile sebesar 0,20 meter, cukup aman dan stabil terhadap beban statik maupun dinamik. Selisih diplacement vertikal maksimum dua titik fondasi pada model gemetri I akibat akumulasi pembebanan menyebabkan angular distortion sebesar 0,2159 cm (1/1112) masih relatif kecil dari angular distortion izin (1/750). Simpangan horisontal maksimum fondasi dan bangunan yang terjadi akibat beban gempa 355,4g adalah sebesar 0,379%,  masih relatif aman jika ditinjau terhadap simpangan izin sebesar 1,54%. Software PLAXIS terbukti mampu memodelkan perilaku dinding goa dan struktur yang memikul beban statik dan dinamik dengan cukup baik.
Analisis Kelongsoran Lereng Akibat Pengaruh Tekanan Air Pori di Saluran Induk Kalibawang Kulonprogo Subiyanti, Hesti; Rifa’i, Ahmad; Jayadi, Rachmad
Jurnal Semesta Teknika Vol 14, No 1 (2011): MEI 2011
Publisher : Jurnal Semesta Teknika

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

During rainy seasons, landslide occurs every year in Talang Bawong, Kalibawang Irrigation Channel thatcan damage houses, school building, bridge and the channel. Considering this fact, a numerical analysis by modeling the slope at the site was conducted. The objectives of this research were to identify the rain characteristic in the research site and to recognize its influence towards the change of water pressure in soil as well as the slope failure. The input data of this analysis were slope topography, physical and mechanical properties of soil applied. Groundwater flow in the slope model was numerically simulated by using SEEP/W software. Designed rainfall with appropriate return period was determined by analizing the maximum daily rainfall data with the aid of HAVARA software, while rainfall depth distribution was completed by applying frequency analysis. The historical daily rainfall data (1985 – 2004) were obtained from Kalibawang rain stasiun. Six rainfall models, as follow: initial condition (no rain) (model I), heavy rain in a short duration (model II), normal rain 25 mm and 40 mm in a long duration (model III), normal rain 20 mm in a long duration (model IV), heavy rain followed by normal rain 20 mm (model V), and normal rain 20 mm followed by heavy rain (model VI) Were analyzed. The output of the simulation was water pressure distribution data, which in turn being used as input data in analyzing slope stability using the SLOPE/W software. The result of the research showed that the highest rainfall with 2-year-return period was 114 mm while the dominant duration was 4 hours/day, and it was applied in the model II. The result showed that, a normal rain in a long duration is more severely influenced the change in water pressure than a heavy rain in a short duration. The safety factors are 1,444 for no rain condition, 1,418 for 114 mm rain for 4 hours, 1,208 for 25 mm and 40 mm rains, 0,982 for 20 mm rain, 1,397 for heavy rain followed by normal rain, and 1,402 for normal rain followed by heavy rain. In addition, a 20 mm normal rain on the 61st  day resulted in the most severe influence on the slope failure. 
Pengaruh Sikap Auditor Terhadap Efektivitas Pelaksanaan Audit Kinerja Mariani, Eny; Rifa’i, Ahmad; Inapty, Biana Adha
Assets Vol 5, No 2 (2015): Fakultas Ekonomi dan Bisnis Islam
Publisher : Assets

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Pelaksanaan audit kinerja dikatakan efektif apabila dapat memberikan dampak perubahan dalam pengelolaan kegiatan auditi ke arah yang lebih baik. Penelitian ini bertujuan untuk menguji pengaruh sikap sukarela auditi, rekomendasi auditor, kompetensi auditor dan independensi auditor terhadap efektivitas pelaksanaan audit kinerja baik secara parsial maupun simultan. Populasi adalah seluruh pegawai Inspektorat se-Pulau Lombok yang melaksanakan pemeriksaan. Sampel diambil menggunakan purposive sampling. Kriteria didasarkan pada pemeriksa yang merupakan Pejabat Fungsional Auditor dan P2UPD. Data diperoleh dengan menyebarkan 129 kuisioner pada responden, yaitu seluruh Pejabat Fungsional Auditor dan P2UPD yang ada di 6 Inspektorat provinsi/kabupaten/kota se-Pulau Lombok Provinsi NTB. Data dianalisis  menggunakan Regresi Linier Berganda. Hasil penelitian ini menunjukkan bahwa sikap sukarela auditi, rekomendasi auditor, kompetensi auditor dan independensi auditor berpengaruh secara simultan terhadap efektivitas pelaksanaan audit kinerja. Sementara sikap sukarela auditi, kompetensi auditor dan independensi auditor berpengaruh signifikan terhadap efektivitas pelaksanaan audit kinerja. Sebaliknya rekomendasi auditor tidak berpengaruh signifikan terhadap efektivitas pelaksanaan audit kinerja. Variabel sikap sukarela auditi, rekomendasi auditor, kompetensi dan independensi auditor mampu menjelaskan variabel efektivitas pelaksanaan audit kinerja sebesar 44,1%. Sedangkan sisanya sebesar 55,9% dipengaruhi variabel lain di luar model.
Behavior of Expansive Clay of Ngawi Region (East Java) Under Water Content Variation Sudjianto, Agus Tugas; Suryolelono, Kabul Basah; Rifa’i, Ahmad; B Mochtar, Indrasurya
Civil Engineering Dimension Vol 11, No 2 (2009): SEPTEMBER 2009
Publisher : Institute of Research and Community Outreach - Petra Christian University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (291.438 KB) | DOI: 10.9744/ced.11.2.pp. 100-105

Abstract

When expansive clay is wetted, deformations occur both vertically and laterally. If it is tested in an oedometer ring apparatus the lateral deformation will be restrained by the wall of the ring. This paper present the results of an experimental investigation using modified oedometer test for measuring the vertical and lateral swelling potential and lateral pressure of disturbed expansive clay soil. Series of modified oedometer tests were conducted with initial water content of 20%, 25% and 30%, to predict the vertical and lateral swelling potential and lateral swell pressure. The results of the test show that the percentages of the vertical swell is bigger than the lateral swell. Both vertical and lateral swell, linearly decrease with increasing initial water content. The lateral swell pressure also decreases with increasing initial water content.
Perbaikan Tanah Dasar Jalan Tol Semarang – Demak Menggunakan Bahan Aditif Dan Perkuatan Kolom Stabilisasi Anggraini, Anindita Dwi; Rifa’i, Ahmad; Faris, Fikri
Rekayasa Sipil Vol 12, No 1 (2018)
Publisher : Department of Civil Engineering, Faculty of Engineering, University of Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1288.939 KB)

Abstract

In Semarang there is often a flood of sea water that swamp the road. This happens because the ground is lower than the water level, load-carrying capacity is deficient. Following up on this, a new road network is needed as a toll road. To accomplish the problem, it is necessary to increase the load-carrying capacity by improve the subgrade on the toll road using additive and strengthen the stabilization column. Additives used in the form of additives made of inorganic materials containing compounds of calciumchloriddihydrat with pH of 8.24 which has ion bonding energy is greater than the metal material on the surface of the soil grains. The general composition consists of carbon elements 72.78%, hydrogen 21.11%, and nitrogen 1.36%. The research was conducted on soil mix, additive material by comparison 1 gram of additive, 1 liter of water and variation of cement content like 4%, 5%, 6%, 7%. To get the optimum mix for soil improvement. Then numerical analysis by using Plaxis Software v.8.6 with variation of soil thickness and column length stabilization. Test results show that the soil is high-plasticity clay. The soil stabilization was eligible for soil compressive strength testing for layers of soil composite cement foundation of 24 kg / cm2. Soil compressive strength testing of soil stabilization is 2,47 kg/cm 2 with 7% cement and addictive. Based on numerical analysis with plaxis v 8.6 software, the deformation value in the model with 5 m thick soil stabilization and 50 m stabilization column length has met the embankment degression limit according to the PU guideline that is 20 mm for the 1st class road. For the value of road stability safety factor, eligible value 1.4.