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Kajian ini membahas karakteristik fisik dan mekanik komposoit semen limbah partikel bambu dan serat aren dengan variasi komposisi campuran untuk memperoleh formulasi empiris guna memprediksi sifat mekaniknya. Pembuatan dan pengujian benda uji dilakukan sesuai standar ASTM D 143 dengan 5 variasi komposisi jumlah campuran partikel bambu dan serat aren masing-masing 0%:100%; 25%:75%; 50%: 50%; 75%:25%; dan 100%: 0%; dengan kerapatan direncanakan 0,8 g/cm3. Variasi lainnya adalah ukuran limbah partikel bambu yaitu tertahan saringan 5 cm x 5 cm; 1 cm x 1 cm, 0,5 cm x 0,5 cm, dan 0,2 cm x 0,2 cm. Jumlah semen divariasikan dengan perbandingan bahan dan semen 1:2, 1:3, dan 1:4. Hasil kajian memperlihatkan bahwa perilaku sifat fisik terbaik diperoleh pada perbandingan bahan dan semen 1:4 dan ukuran partikel bambu 0,2 cm x 0,2 cm dan 0,5 cm x 0,5 cm. Kajian sifat mekanik menunjukkan tegangan lentur (MOR) balok/papan semen berkisar 4,77-6,59 MPa, dengan hasil terbesar pada komposisi balok semen campuran partikel bambu dan serat 50%:50% dengan ukuran partikel bambu 0,2 cm x 0,2 cm dan panjang serat aren 5 cm. Modulus elastisitas (MOE) balok semen tertinggi diperoleh pada campuraan partikel bambu dan serat aren 100%:0% dan ukuran partikel bambu 0,2 cm x 0,2 cm. Kandungan semen terbaik untuk MOE sebesar 2283,02 MPa didapat pada perbandingan bahan dan semen 1:3.

Prestressed precast modular concrete slabs function rigid pavement, supporting vehicle loads above it on subgrade with relatively low bearing capacity. This slab measures 2000 x 850 x 150 mm3 of regular reinforced concrete (old production) or prestressed concrete (new production) quality K-500. After several times of use, damage occurs mainly at the end of the slab in the form of spalling. The objectives of the study and evaluation were: (1) observing damage; (2) material quality data; (3) numerical modeling by taking into account material properties, loading and soil conditions; and (4) providing slab design recommendations including materials and geometrics. The method of study and evaluation of slab damage was done by observing the damage, taking concrete core-case and testing it in the laboratory, and modeling the slab structure with various parameters (soil data, concrete quality and slab geometry). Field observations and analysis results show that concrete slab spalling occurs initially at the edge (850 mm wide) which in turn causes the effectiveness of the pre-tension force to be suboptimal and finally the concrete spalling volume increases. Apart from the frequency of collisions during installation and slab deformation when supporting vehicle loads. Concrete spalling problems also due to inappropriate concrete quality.

Abstrak -Di daerah Jalan Gatot Subroto Barat, Denpasar terjadi permasalahan yang terjadi di daerah ini adalah tower PLN SUTT 150 kV no.71 menghalangi jalan masuk ke lahan milik warga, sehingga harus melakukan rekayasa DPT dengan memotong sebagian tanah timbunan serta DPT tipe gravitasi yang telah ada sebelumnya tanpa mengurangi keamanan konstruksi tower SUTT dan mengganti dengan DPT dari tiang bor (bored pile). Setelah melakukan penyelidikan tanah dan diuji di laboratorium dihasilkan nilai sudut geser tanah (ϕ) = 30º dan berat volume (γ) = 1,6 gr/cm Abstract -In area Jalan Gatot Subroto Barat, Denpasar there is a problem when the tower PLN SUTT 150 kV no.71 blocking the entrance to the land belonging to the people, so it must be modified of retaining wall by cutting a portion of the soil embankment and existing gravity retaining wall without decreasing safety SUTT tower construction, and replace by bored pile retaing wall. After investigating the soil and tested in the laboratory generated angle of friction (ϕ) = 30º and density (γ) = 1.6 g/cm 3 . Based on the analysis obtained the maximum moment (M max) = 2,384.248 kg m and maximum shear force (D max) = 1,098.952 kg. Retaining wall calculation results the composition of bored pile of reinforced concrete with a diameter of 40 cm was installed in the ground 4.5 m and height 3.5 m above the ground, so it takes a bored piled with 8 m long by 35 pieces. Bored piled with diameter 40 cm using 6D16 main longitudinal reinforcement and shear reinforcement using Ø10-250. The new land area obtained as a result of the reduction of existing retaining wall in the north (front side) is 5.0 x 11.7 m 2 and access roads in the eastern part wider from 2.5 m to 3.9 m.

Glue-laminated (glulam) bamboo potentially used to be a substitute for wood as a building material, because it can be produced within four to five years of planting. Mechanical properties of glulam bamboo should be well understood by support the wider application of this new material in structural components. This study focused on embedding strength evaluation of glulam bamboo, were required to evaluate lateral resistance of dowel-type joints. The evaluation was carried out using experiment according to ASTM D5764 and numerical analysis performed with ADINATM. Material were considered in the experiment consist of bolt 12.2 mm diameter, a range of specific gravity of glulam bamboo from 0.57 to 0.79 and moisture contents varies from 11.14% to 12.45% were considered in the experiment. There were three groups of specimens: group A parallel loading to grain radial; group B parallel loading to grain tangential; and the last was group C perpendicular loading to grain. Glulam bamboo were modeled as an orthotropic nonlinear material whiles the dowel was assumed as perfectly rigid material. Contact condition between dowel and laminated bamboo was considered and the numerical model was solved under the plane stress assumption with deformation control. The experimental result was indicated that embedding strength parallel to grain (group A and B), it was significantly higher than group C. This phenomenon was apparent in the numerical study as well. The embedding strength of laminated bamboo (Fe) could be well predicted as 78.4G for parallel to grain radial, 72.79G for parallel to grain tangential; and 69.96G for perpendicular to grain radial, where G is the specific gravity.