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The collapse of buildings during seismic shocks resulted in many fatalities due to the earthquake. Existing structures constructed under previous regulations with an earthquake intensity value less than the present seismic intensity are the most affected, particularly low-rise buildings. The Federal Emergency Management Agency (FEMA) releases codes to evaluate the vulnerability of buildings to earthquakes to anticipate the possibility of damage to existing structures caused by earthquakes. According to the FEMA P154-2015 code, in the regulation, there are stages consisting of Tier 1 (screening), Tier 2 (evaluation), and Tier 3 (detailed), as well as building evaluation with the Rapid Visual Screening (RVS) approach. The vulnerability of twelve existing buildings in Surakarta and Yogyakarta Indonesia has been assessed, those are low-rise buildings (2-3 floors) that were built around 1980 and still stand as public facilities. The evaluation result of existing buildings with the RVS method, eight buildings are declared safe against earthquakes (S≥2) and four buildings are considered vulnerable to earthquakes (S

Geopolymer concrete is concrete without cement. Cement replacement due to cement production has resulted in a global warming effect. Fly ash as a substitute for cement is a waste of coal production containing pozzolan properties. Concrete must have reliable mechanical properties of the modulus of rupture. This research aims to study the influence of the modulus of rupture on the steam curing of geopolymer concrete-based fly ash as a substitute for cement and alkaline activator of 12 Mol NaOH: Na2SiO3 (3:1). The applied steam curing temperatures are 60oC, 70oC, and 80oC. After steam curing, the sample is stored at ambient curing and submerged in water. The sample beam is 15 x 15 cm x 60 cm to find the value of the modulus of rupture. The test results obtained a modulus of rupture concrete geopolymer steam curing temperature of 80 and ambient curing of 3.87 MPa. Steam curing of 70oC and ambient curing of 3,71 MPa. Steam curing of 60oC and the ambient curing is 2.71MPa. It can be concluded that the higher the steam curing temperature the value of the modulus of rupture is higher.

Agriculture is an important sector in the national economy, therefore the development priority is placed on development in the economic sector with an emphasis on the agricultural sector. Income in farming activities generally cannot be stable from time to time. The objectives of this study include (1) to determine the relationship between farmer characteristics and farmer income in farmer groups BPP Plumbon District, (2) to determine the relationship between the implementation of organic rice farming systems and farmer income in farmer groups BPP Plumbon District, (3) To determine the relationship between the characteristics of farmers and the implementation of organic rice farming systems with farmers' income in the BPP Farmer Group, Plumbon District. The research design used in this study was a quantitative research with a descriptive survey research technique. The results showed that: (1) there was a moderate relationship between farmer characteristics and farmer income in the BPP Farmer Group in Plumbon District, namely 0,703, (2) there is a moderate relationship between the application of organic rice farming systems and farmers' income in the BPP Farmer Group in Plumbon District, namely 0.643, (3) there is a significant relationship between farmer characteristics and the application of organic farming systems to farmer incomes. Based on the output that tarithmetic X1 = 7.551 and X2 = 5.252> ttable which is 1.998. [ABSTRACT FROM AUTHOR]

Two test objects of concrete frame behavior against lateral loading were performed by applying structural analysis with the wall as diagonal reinforcement in modeling. The results of the structural analysis indicated that concrete frames with walls have better performance than concrete frames without walls. Twelve objects consisting of the frame without the wall, frame with the wall, and frames with a group of steel and bamboo as diagonal reinforcement at brick walls and concrete panel walls were tested at the laboratory with monotonic lateral forces that work parallel to the wall as the illustration of earthquake loads. The diagonal reinforcement elements can spread the force received by the wall and increase the strength of the wall as well as enhance the stiffness of the structural system at once. Bracing contributes to increasing the strength, especially in resisting the compressive forces due to the earthquake loads. Deformation occurs in the opposite direction between compression path and tension path at the diagonal area. The failure in the concrete frame can be caused by the in-plane force parallel to the wall. Bamboo is quite effective to be used as a substitute for steel reinforcement as bracing material despite its shortage of steel quality.