Currently, founded many non-engineered bridges that are damaged in the remote areas. The alternative to solving the bridge problem in remotes areas for pedestrians is using a truss bridge system with the cold-formed steel material. The truss bridge system is the ideal shape for coldformed steel material that is weak to buckling. This study discusses the effect of different truss shapes to the weight and deflection ratio that occurs due to the pedestrian load on the small span (L = 4m). The proposed truss shape refers to general applied forms that will be developed based on SNI 1725-2016 for loading criteria and cold-formed steel cross-sectional analysis based on SNI 7971-2013. The prototype of truss shape will be tested at the laboratory in model scale. The results of this study will introduce a new truss shape of the cold-formed steel bridge with the smallest deflection Keywords: shape of truss bridge, cold-formed steel, pedestrians, deflection AbstrakPada daerah terpencil banyak ditemui jembatan sederhana (non-engineered bridge) yang mengalami kerusakan. Salah satu alternatif untuk menyelesaikan masalah jembatan pada daerah terpencil untuk pejalan kaki adalah menggunakan jembatan rangka dengan material canai dingin. Jembatan sistem rangka adalah bentuk yang ideal untuk material canai dingin yang rawan mengalami tekuk. Beberapa bentuk jembatan rangka yang banyak diaplikasikan adalah tipe Warren truss, Pratt truss, Howe truss dan K-truss. Penelitian ini membahas pengaruh bentuk rangka terhadap rasio berat dan lendutan yang terjadi akibat beban pejalan kaki pada bentang pendek (L = 4m). Dalam pengembangan bentuk rangka ini mengacu pada bentuk rangka yang banyak diaplikasikan, menggunakan pembebanan sesuai SNI 1725-2016 dan analisa penampang canai dingin berdasarkan SNI 7971-2013. Usulan bentuk rangka yang dihasilkan juga akan dilakukan pengujian beban di laboratorium. Hasil dari penelitian ini diharapkan dapat diusulkan alternatif bentuk rangka baru jembatan canai dingin dengan lendutan yang paling kecil. Kata kunci: bentuk jembatan rangka, canai dingin, pejalan kaki, lendutan 1. Pendahuluan Jembatan merupakan suatu konstruksi bangunan yang memiliki peranan penting untuk menghubungkan antar satu daerah dengan daerah yang lain. Pada daerah terpencil masih banyak kita temui jembatan sederhana (non-engineered bridge) yang biasanya dilewati oleh masyarakat dengan berjalan kaki, dimana hal tersebut dapat membahayakan masyarakat selain umur manfaat jembatan sederhana tersebut yang seringkali tidak panjang dan cepat mengalami kerusakan baik karena beban yang melintas, maupun karena pengaruh alam. Salah satu alternatif untuk menyelesaikan problematika jembatan pada daerah terpencil untuk masyarakat pejalan kaki adalah dengan menggunakan jembatan rangka yang terbuat dari canai dingin (cold formed).Bahan canai dingin memiliki kelebihan dalam hal kemudahan pelaksanaan karena beratnya ringan dan sistem penyambungannya relatif mudah. Namun karena memiliki berat yang ringan dan

Geopolymer concrete is an example of innovative concrete that does not use cement as a binder and generally fly ash used in recent research. However, fly ash is categorized as a hazardous and toxic waste [8]. This research studied about another binder, besides fly ash, in this case is rice husk ash made as a geopolymer paste alkali activated by a chemical mixture of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) confronted to a fly ash mixture paste as comparative material. The compositions made were, 100% rice husk ash, a mixture of 50% rice husk ash and 50% fly ash, and 100% fly ash as control mixture. After making the mixture, the composition will be tested to setting time-test in the form of paste. The size of specimen was cylindrical 2,5 cm in diameter 5 cm in height and cube size 15 cm x 15 cm x 5 cm. Each type of specimen was projected to porosity test, compressive strength test, UPV (Ultrasonic Pulse Velocity) and permeability test on 3 days, 28 days and 56 days of sample’s age. From the result of setting time, it was found that the composition of 100% rice husk ash had the longest on binding, which were 129 minutes for early binding and 170 minutes for late binding. The lowest result of porosity test was 100% of fly ash at 56 days of sample’s age testing with a porosity of 20%. The lowest result of compressive strength was 100% of rice husk ash tested in 3 days of sample’s age showed a compressive strength at 0.65 MPa. Based on the test results of UPV (Ultrasonic Pulse Velocity), the lowest value of wave velocity was 531.667 m/s, belong to 100% rice husk ash mixture at 3 days of sample’s age testing, with very poor binder quality qualification. The test result of highest permeability kT value with very poor-quality index binder was 100% rice husk ash with period of testing time in 3 days 0,047.10-16 m2.

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Concrete is a composite material for it is consisted of some other materials, being mixed until homogen and monolith. But, however the mixture diversification or certain compaction method are being done, there is chance of bubbles or air pores occurance who degrade the design strength. Furthermore, concrete curing holds an important role for preventing the rush of initial cracks. The emerging of initial cracks follow concrete's volume-shrinkage, which is led by fast evaporation and the hydration process. This study observed concrete's compression strength, represented by six type of mashing-quantity, 0, 5, 10, 15, 20, 25 times of mashing per layer. Each type is represented by two samples. Samples made are cylindrical with 150 mm in diameter and 300 mm in length. Material specification is conventional industrial concrete K-250 with 120 mm slump. Samples were made by single mixing in Indonesia's average weather and temperature. After being molded, samples were stored in environmental ambiance (exposed by direct sun-ray, wind, etc.). From the experimental research, we're achieving the optimum compression strength of 20 times mashing per layer-sample, 15,09 MPa. The exposure of environmental ambiance reduces 30% of concrete's design strength. Kata kunci: kuat tekan, benda uji silinder, jumlah rojokan, paparan lingkungan.