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Crossties that was installed as a confinement in the compression zone of the beam is proven can increase the ductility, especially when receiving the earthquake load. Using an experimental study, this paper  explains  the effect of crossties which was installed in compression zone of the beam. The model was a simplification of the plastic hinge of the beam. The beam was enlarged in the center of the span and would be loaded with a cyclic of point load, so as to produced the largest moment and shear fields in the face beam of the column. Moreover, the loading was provided by the displacement control system to achieve the ultimate condition. The results show that the crossties significantly increases the displacement and curvature ductility of the beams of 58.7% and 78.2%, respectively, compared to the beam without confinement. In addition, the load cycle formed by cyclic loading increases to 43 cycles in beam with crossties, meanwhile the beam without confinement can only survive up to 33 cycles. The crossties could also increase the cumulative value of inelastic displacement that occurs up to 98%, whereas its  energy dissipation value is six times than the beam without confinement. On the other hand, the maximum load and capacity moment only increase about 6.5%.

The rigid pavement on many roads is considered as a solution due to the increasing traffic load that requires high performance and durability of the road construction. However, the implementation of rigid pavement takes a longer time to reach its concrete strength until the road operation. Some industries have developed pavement from precast concrete panels to reduce construction time. This paper discusses the comparison of rigid pavement between precast concrete and conventional concrete. Two road sections are Jalan Margomulyo Surabaya using precast-concrete-pavement and Jalan Semarang-Jambu using conventional-concrete-pavement chosen as research objects. Cost, construction time, serviceability, and traffic performance are the four variables reviewed in this study analyzed using the Analytical Hierarchy Process (AHP) method with considers 15 competent experts as respondents. Based on the analysis shows that a road improvement project by using precast-pavement is more effective and efficient with a score of 58.42 %, while the score of conventional concrete is 41.58 %.

Composite structures of concrete slabs and steel beams require shear connectors to transfer shear force between steel beams and concrete slabs. The strength of stud shear connector specified on SNI 03-1729-2013 only considers the effect of stud diameter, however the length of a stud may influence its behavior and strength. This research observes the effects of length and diameter (𝓁/𝒹) of shear connectors on the strength. This research was conducted using the push out method explain in AS-4347- Part I. The test specimens observed in this research were concrete and steel composites, composing IWF 350x175x11x14 mm and concrete blocks of size 450x225x160 mm. The studs were made of steel reinforcements with diameter (𝒹) of 10, 16 and 22 mm, were welded on IWF with 5 mm weld thickness. The length of studs for each stud diameter were 4d, 5d, and 6d. The results indicate that the increase in stud diameter will increase the load capacity of stud. The length of studs effect its load capacity. A slim stud experiences large bending moment at the base of the shear connector. The results show that the highest value of load capacity is measured at specimens with 𝓁/𝒹 ratio of 5.

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