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Bamboo has been significantly and rapidly used to build temporal and permanent structures since time immemorial. However, this renewable natural material has a low bearing capacity, limiting its application to structures under light loads. Therefore, this research was carried out to determine an innovative scheme capable of enhancing bamboo's load-bearing by filling the cavity with cement mortar. Furthermore, a study was carried out to experiment flexural load carrying capacity and the deflection of mortar-filled structural bamboo by considering the diameter and node parameters. A total of 12 specimens were examined using a four-point bending protocol. The result showed the ultimate flexural load carrying capacity of mortar-filled bamboo specimens are higher than those of the conventional bamboo specimens. Specifically, mortar filled bamboo specimen with a diameter of 70 mm was significantly better, 41.10 and 47.06%, as compared than the conventional bamboo in terms of its flexural load carrying capacity for specimen without and with nodes, respectively. Increases in flexural load carrying capacity were also observed for the mortar-filled bamboo specimens having 80 and 90 mm diameter and these observed increases were recorded as 104.55 and 112.00%, and 48.72 and 60.74%, respectively for specimen without and with nodes. Furthermore, the deflection of mortar-filled bamboo elements are substantially greater than those of conventional. Finally, the advantages of the bamboo diameter and bamboo nodes on the flexural load carrying capacity indicated that these essential findings need to be carefully considered in designing structural elements for both mortar-filled and conventional bamboos.

Beton merupakan material yang sering dipakai pada bangunan sipil karena kuat tekannya yang tinggi dan memiliki durabilitas yang baik. Material ini tidak sepenuhnya impermeable terhadap penetrasi air karena terbentuknya jutaan kapiler pada saat proses pembuatan beton. Senyawa korosif masuk bersama air melalui kapiler ini. Oleh karena itu diperlukan bahan tambah yang bisa memperbaiki sifat fisik beton. Penggunaan calcium stearate telah terbukti mampu menurunkan serangan korosi melalui uji korosi dipercepat. Sayangnya masih jarang penelitian yang menguji infiltrasi air ke dalam beton menggunakan permeabilitas. Tujuan penelitian ini adalah untuk mengetahui pengaruh penambahan calcium stearate terhadap nilai penetrasi air. Dosis calcium stearate yang digunakan yaitu 0, 1, 2 dan 3% dari berat semen. Mutu beton yang digunakan adalah 40 MPa. Benda uji berupa kubus dengan sisi 15x15x15 cm. Hasil penelitian menunjukan adanya penurunan nilai penetrasi air akibat penambahan calcium stearate. Nilai penetrasi pada masing-masing kadar calcium stearate 0, 1, 2 dan 3% adalah sebesar 1.27, 1.07, 0.93 dan 0.70 cm. Hal ini menunjukan bahwa calcium stearate dapat menurunkan penetrasi air ke dalam beton.

The Oral and Dental Hospital of Jenderal Soedirman University was built in 2008. This building consists of 4 stories equipped with inpatient rooms, X-ray rooms, and laboratory. It is expected that with a main function as a public facility with a large number of people doing activities within it, the building has a high level of security when an earthquake occurred. This study aims to perform a preliminary seismic hazard assessment, i.e. an evaluation using a Rapid Visual Screening method and a Tier 1 Evaluation using FEMA 310. The results of the Rapid Visual Screening are a final level 1 score compared with a cut-off score of +2.00. If the final level 1 score is less than or equal to +2.00, the building requires the tier 1 evaluation. The Tier 1 Evaluation using FEMA 310 is performed to identify the potential deficiencies of the building. It consists of 3 sets of checklists that allow a rapid evaluation of the structural, nonstructural and foundation/geologic hazard elements of the building and site conditions. If the result of the tier 1 evaluation shows that the potential deficiencies of the building are identified, a more detailed evaluation of the building is recommended to perform. The results of the analysis show that from the Rapid Visual Screening method, the building has a final level 1 score of +0.3, while from the Tier 1 Evaluation there are Not-Compliant (NC) statements for structural and nonstructural components.

The total weight of the building is greatly influenced by the self-weight of the reinforced concrete. The hollow core slab is one of alternatives to reduce its self-weight. On the other hand, with advancements in the quality of materials, workmanship and new technologies, precast concrete has become popular in the construction industry. This study discusses the flexural behavior of precast hollow core slab with different type of reinforcements. The test specimens consist of a solid slab as a reference slab, a hollow core slab type 1 (using PVC pipe to create the cavities), and a hollow core slab type 2 (using styrofoam to create the cavities). The diameter of steel reinforcements used in this study are 10 mm plain and deformed bars, 12 mm plain bars, and 13 mm deformed bar. The slab thickness was 12 cm. The results showed that hollow core slab type 1 and type 2 can reduce the weight by 24% and 25% as compared to the solid slab. Flexural strength of hollow core slab type 2 is higher than the hollow core slab type 1. However, it is lower than the solid slab with all variations in reinforcement diameter. The value of flexural stiffness of the solid slab is greater than hollow concrete slab type 1 and type 2. Cracks that occur in solid slab are distinguished as flexural crack, while the cracks that occur in the hollow core slab type 1 and type 2 are shear cracks.

Segmental precast reinforced concrete with waste tyre as reinforcement is one method of simplifying and speeding up the installation of on-site concrete structures. This study determines the connections between segmental precast reinforced concrete and waste tyre as reinforcement. The dimensions of the specimens used in the experiment are 15 cm × 15 cm × 50 cm. The size of recycled tyre as reinforcement used is 10 mm × 10 mm in cross section view. One specimen is concrete beams with waste-tyre reinforcement as a standard test specimen. Four other specimens are in the form of segmental precast concrete beams with segmental connector lengths of 10 cm, 15 cm, 20 cm, and 25 cm. Furthermore, concrete beam specimens are tested to investigate their flexural capacity with a three-point loading method. The results show that the length of the reinforcement fitting does not significantly affect the flexural strength of the beam. The flexural strength capacity of concrete beams reinforced with recycled tyre with these connectors is approximately 10 kN.Segmental precast reinforced concrete with waste tyre as reinforcement is one method of simplifying and speeding up the installation of on-site concrete structures. This study determines the connections between segmental precast reinforced concrete and waste tyre as reinforcement. The dimensions of the specimens used in the experiment are 15 cm × 15 cm × 50 cm. The size of recycled tyre as reinforcement used is 10 mm × 10 mm in cross section view. One specimen is concrete beams with waste-tyre reinforcement as a standard test specimen. Four other specimens are in the form of segmental precast concrete beams with segmental connector lengths of 10 cm, 15 cm, 20 cm, and 25 cm. Furthermore, concrete beam specimens are tested to investigate their flexural capacity with a three-point loading method. The results show that the length of the reinforcement fitting does not significantly affect the flexural strength of the beam. The flexural strength capacity of concrete beams reinforced with recycled tyre with thes...

Composite steel-concrete trusses are among the most economical systems for building, particularly for greater spans, allowing proper internal space utilization without limiting columns. This paper examines 12 lab tests on two types of composite steel-concrete truss elements compared with the conventional steel truss element as a control specimen. The experiments investigate the load-carrying capacity of the truss element with different configurations under monotonic loading. The study on the specimen’s failure modes was based on the welded joints. The obtained results were compared with analytical evaluations of typical resisting mechanisms of steel-concrete composite, reinforced concrete, and steel structures with updated Indonesian design codes. The basic features of the steel-concrete truss elements discussed quantitatively and qualitatively.

The use of lightweight concrete as building construction material can reduce the building’s self-weight and its vulnerability to earthquakes. This paper presents an experimental study on the mechanical properties of lightweight aggregate concrete reinforced with soda can waste fibre. The addition of the fibres may help prevent environmental damage. Twenty-four concrete cylinder specimens with a height of 300 mm and a diameter of 150 mm were cast. The volume fraction of the fibre was varied between 0, 0.3, 0.6, and 0.9%. To facilitate the casting process, superplasticizer was added in a content of 2% by cement weight. We found that the fibrous concrete produced can be categorized as lightweight concrete with a density below 2000 kg/m 3 . The mechanical property that experienced the highest improvement, amounting to 61.00%, was the split tensile strength. The optimum fibre volume fraction for better performance in terms of strength is 0.3%.

The inpatient building of Goeteng Hospital, Purbalingga, Indonesia, which was built in 2012, is a building with risk category IV. Due to the irregular configuration of the structure, this building has considerable earthquake vulnerability. This study aims to evaluate the symmetrical performance of the Goeteng Hospital inpatient building using pushover analysis. The results of the study show that the basic shear force received by the inpatient building of Goeteng Hospital is equal to 10064.421 and 5655.626 kN in the X and Y directions, respectively. The structure deviation ratio that occurs below 1% is 0.17% for the X direction and 0.24% for the Y direction. Thus, the seismic performance of the Goeteng Hospital inpatient building is categorized as immediate occupancy, where it is predicted that there is no damage, meaning that its structure, strength, and stiffness are about the same as the conditions before the earthquake. Non-structural components are still in place and most are still functioning if the utility is available. The building can still function without the need for repair work.

Indonesia is one of the wealthiest botanically countries in the world. There are more than 130 species of Bamboo can be found in this country. Bamboo is a natural raw material which is one of the fastest growing plants that has many advantages as a construction material. We conducted an experimental investigation to study the performance of the precast segmental bamboo reinforced concrete beams with bolted connections subjected to flexural loads. Tests were carried out on three specimens with dimensions of 120 mm x 150 mm x 1000 mm, consisting of one control beams (BK), one precast segmental bamboo reinforced concrete beam with four bolted connections (BS4), and one precast segmental bamboo reinforced concrete beam with six bolted connections (BS6). We found that the load carrying capacity of precast segmental bamboo reinforced concrete beams with four bolted connections (BS4) and six bolted connections (BS6) had a decrease of 57.99% and 55.62% respectively compared to control beam (BK). Similarly, the deflection ductility index of the precast segmental bamboo reinforced concrete beams with four bolted connections (BS4) and six bolted connections (BS6) had a decrease of 49.78% and 46.59% respectively compared to control beam (BK). Also, we observed that the crack pattern developed in the control beam indicates a flexural failure mechanism while the crack pattern developed in the precast segmental bamboo reinforced concrete beams indicates a shear failure mechanism. As a conclusion, this study will significantly contribute to the growing development of research on the bolted connection system in bamboo reinforced concrete members, especially in Indonesia.

This study aims to determine the effect of rice husk as a source of substitute fuel on the manufacture of cement at the industry scale. The parameters tested include the physical properties of the cement consisting of the Blain fineness test, false set, cement setting time, and mortar compressive strength at 3, 7, and 28 days. The average values for the results of these tests on cement produced using rice husks as a substitute fuel were 380 m2/kg, 81%, 132 minutes, 253 minutes, and 225, 298, and 379 kg/cm2, respectively. Based on the test results, we have shown that rice husk ash has a good effect on the characteristics of cement type I which still meet the standards of SNI-2049-2015.

Production of rice husk in Central Java province is around 2,825,000 tonnes annually. It can be used as an alternative energy source to substitute coal in combustion during cement production. This study was conducted to determine the impact of rice husk as a substitute energy source in cement production. The observations of rice husk comprised calorimetric tests, physical and chemical tests, and percentage rice husk substitution for coal as firing energy. The chemical properties of the cement tested include the chemical content, MgO and SO3 contents, loss on ignition, insoluble residue, and total alkali. The results show that the chemical content of cement which is produced using rice husk as a substitute for coal in the combustion process still meets the Indonesian National Standard.