To find economic mixing proportions of 60MPa high strength self compacting concrete optimizing a multi-objective problem was performed, which was implemented numerically on MathCAD15 to calculate the economic and optimal mix proportion considering multi-objective characterizing the five performances like compressive strength, passing ability, segregation resistance, manufacturing cost and bulk density depending on the factors like water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content.
D-optimal experimental design was employed to model the effect of mixing factors on several performances of 60MPa high strength self compacting concrete and to numerically calculate the optimal mix proportion considering multi-objective characterizing the four performances like compressive strength, passing ability, segregation resistance and manufacturing cost depending on the factors like water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content, the experiments were made at the total 32 experimental points which reduced comparing with standard experimental design.
NSGAⅡ algorithm was employed to optimize the multi-objective problem to find mixing proportions of 60MPa high strength self compacting concrete, which was implemented numerically on MATLAB to calculate the optimal mix proportion considering multi-objective characterizing the four performances like compressive strength, passing ability, segregation resistance and manufacturing cost depending on the factors like water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content.
Multi-objective optimization using response surface methodology-based surrogate model was employed to find optimal design parameter of TMD installed on structure under the El Centro earthquake. It is found that the RSM based weighted multi-objective optimized damper improves frequency responses and root mean square displacements of the structure without TMD by 31.6% and 82.3% under El Centro earthquake, respectively, and has an equal or higher performance than the conventionally designed dampers with respect to frequency responses and root mean square displacements and when applied to earthquakes.
Multi-objective optimization coupled with GA-ANN Metamodeling Method and NSGAⅡ was implemented to optimize TMD installed on 10 story structure under El Centro earthquake. Layer number and nodes of ANN were optimized by use of genetic algorithm and NSGA-Ⅱalgorithm was applied to solve multi-objective optimization problem prepared by GA-ANN metamodel. It is found that the GA-ANN multi-objective optimized damper improved frequency responses and root mean square displacements of the structure without TMD by 34.7% and 76.4% under El Centro earthquake, respectively.
Tuned Mass Damper (TMD) and viscoelastic damper (VED) is a well-known vibration absorbing equipment in the civil engineering realm. Although the dampers are typically used separately, combined use of dampers worth investigation. For that purpose, a numerical model of multi-story building equipped with TMD and VED was developed using finite element software SAP2000. In this study, modal parameter based distribution of hybrid damper system (HDS) using Tuned Mass Damper (TMD) and viscoelastic damper (VED) together has been adopted to reduce the seismic response of the structure.
The intent of this research is to apply DOE in mix proportioning of high strength self-compacting concrete (HSSCC) and to assess the effect of different process parameters on HSSCC. The effect of water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content on compressive strength, passing ability, and manufacturing cost were studied.
This study investigated the effect of surface water on concrete substrate on adhesive strength in tension of very high flowable SBR-modified cement mortar. Polymer cement ratio(P/C) were 10, 20, 30, 50 and 75% and the weight ratio of fine aggregate to cement were 1:1 and 1:3. The specimens obtained with different P/C and C:F were characterized by unit weight, flow test, crack resistance and adhesion test. Three selected specimens among these tested specimens were studied about the effect of surface water evenly sprayed on concrete substrate on adhesive strength.
This study have interests in presenting the process of material optimization design. This study was designed by using design of experiment. To present the form of model and explore the optimal point of response surface model, central composite design(CCD) and Response Surface Methodology(RSM) were used in the design of the experiment and in the analysis of the results.