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The production of Portland Cement (PC) has been shown to be responsible for 5-8% of global CO2 emissions. This has led to class F fly ash based geopolymer concrete being developed as a substiture for PC concrete for to reduce these global CO2 emissions. However, research has shown that each fly ash has unique characteristics and requires a specific mix design for each fly ash. This is can occupy a significant amount of time. Furthermore, before the mix can be adopted for commercial application it requires the long-term durability to be established. This gap is one of the primary limitations delaying the adoption of geopolymer concrete. While each fly ash is unique, they do have common characteristics which can be utilized to optimise the mix design process. Geopolymers are also known to have good durability characteristics, in particular for acid and sulphate exposure. This paper reports the mix design optimisation process for six class F fly ashes from Australia, Sri Lanka and Indonesia. The strength properties and durability performance of the optimised mixes is reported including the compressive strength development, chloride and carbonation resistance together with performance when exposed to sulphate and acidic media for the Indonesian fly ash, including to a simulated peat soil designed to replicate the conditions experienced in Indonesia.

The research was motivated by the lack of student learning outcomes in the material of composing an equivalent force. Student who less actively involved in the learning process, learning group has not been managed well, the student who is good, medium and low receive equal treatment, not to be rewarded for the best student, good and lowest. The good student very extremely rare to help the weaker students. This research makes use of the quantitative method research and models of type STAD cooperative learning with population student of X technic of building construction sanitation and treatment as many as 28 people. Formulation of the problem in this study is how the application of models of type STAD cooperative learning can improve learning outcomes the material of composing an equivalent force and how the response of student in grade at class X technic of building construction sanitation and treatment SMK Negeri 1 Palangka Raya year 2017/2018. Succesful implementation of type STAD cooperative learning models in the material of composing an equivalent force is to know to an increase and decrease in class X technic of building construction sanitation and treatment of the prior action is pre-test to post-test. In the prior action, the student who can achieve the minimum of criteria competition (KKM) as many as 0 (0%) people with average value are 36.79. At LKS execution in a group, the student who is can achieve the minimum of competition as many as 28(100%) people with the average value is 75,34. At the postest after, students who are complete as many as 15(53.57%) with the average value is 59.88 and completeness level is 53.57%. In a totality value, the student who is complete as many as 15(53.57%) with average value is 65.37 and completeness classical is 53.57%. Although the thoroughness of student increased from the prior action to the finish value or after action, the classical or the overall student learning outcomes have not reached 85% KKM set at 70, on an individual basis there is some student who does not complete. Thus it can be retrieved the conclusion by the application of the model of type STAD cooperative learning can improve learning outcomes in class X technic of building construction sanitation and treatment SMK Negeri 1 Palangka Raya year 2017/2018

The durability of concrete has a profound impact on the service life of structural elements. Indonesia has extensive peat soils, which provide a highly aggressive environment for concrete structures. Geopolymer concrete has demonstrated good durability when exposed to acid /sulphate conditions similar to those encountered in peat soils. This paper investigates the performance of geopolymer concretes produced using Indonesian type F fly ash under sulphate and acid chemical attack. Geopolymer concrete specimens have been exposed for 12-months in a range of solutions: 5% sodium sulphate, 5% magnesium sulphate, 1% and 3% sulphuric acid, and simulated peat solution. The mechanical and durability properties of specimens together with a control concrete have been monitored for compressive strength, change in mass, water absorption and volume of permeable voids, ultra pulse velocity, air and water permeability, pH profile, and microstructural analysis (XRD, SEM/EDS). The control immersed in water achieved 56.93 MPa at 12-months of age. Magnesium sulphate exposure had a significant deterioration impact on the compressive strength of geopolymer concrete, demonstrating an 11% reduction in strength, while those exposed to sodium sulphate had an 8.9% increase in strength. Specimens exposed to peat solution displayed a slightly increased strength and those in acid conditions a 1.2% and 4.5% decrease in 1% acid and 3% acid, respectively. In general, the geopolymer concrete displayed a high level of resistance against sodium sulphate, 1% sulphuric acid and simulated peat attack.