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Vietnam is one of the five countries in the world most severely affected by climate change, particularly the north central coastal provinces of Vietnam. In the near future, millions of citizens in these coastal hazard areas will experience difficulties in socio-economic activities and face poverty due to the loss of their agricultural land and even their homes. Therefore, this research study focuses on proposing key components of spatial planning of the north central coastal alluvial zones in Vietnam for adaptation to climate change and sea-level rise to protect inhabitants’ quality of life as well as their agricultural land. The research uses the typical case study of Dong Chau Ngoai village, Dong Minh town, Tien Hai district, Thai Binh province, Vietnam.

The current design method in the ACI building code 318M-14 for reinforced-concrete coupling beams requires complex details, which leads to reinforcement congestion and difficulty in construction. As an original solution for this issue, the use of steel fibres to reduce the amount of transverse and bundled diagonal reinforcement in coupling beams is investigated in this study. In order to estimate the effect of the expected design method, four coupling beam specimens with 2/3 scale subjected to cyclic lateral loads were tested. All specimens were made of steel-fibre-reinforced concrete. One specimen complied with ACI code-specified reinforcement details (for all diagonal, transverse and horizontal bars) and three specimens used bundled diagonal reinforcement with variation in the spacing of stirrups. The global behaviours of the tested coupling beams are discussed, especially focusing on the strength, ductility and energy dissipation capacity as displacement demand increases. The test results illustrate that the lateral force-resisting performance of coupling beams was effectively improved by using steel fibres and bundled diagonal reinforcement, even with a reduced amount of stirrups, compared to that designed following ACI code-specified reinforcement details.

Current design in the ACI building code for reinforced concrete columns under seismic load combinations requires reinforced detailing which causes reinforcement congestion and construction difficulties. As an alternative solution, the use of high-performance fiber-reinforced cement composites (HPFRCC) with an economical type of Poly Vinyl Alcohol (PVA) fibers in column elements was investigated in this paper. Six column specimens with 2/3 scale including three standard reinforced columns and three columns using PVA fibers were tested. In the research work herein presented, biaxial cyclic lateral loads were applied to specimens subjected to either 10% or 30% constant axial loads. The experimental results are presented and the global behaviors of the tested columns are discussed, particularly focusing on stiffness and strength degradations due to increasing cyclic demand. Test results indicated superior damage tolerance and stable inelastic load–displacement responses up to 5% or 9% drift for the HPFRCC columns, even though they suffered severe shear cracks. Specimens without PVA all showed very limited ductility and low strengths.