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- Couple stress fluids (2)
- Finite element. (2)
- Micro-continuum theory (2)
- Squeeze films (2)
- Transfer matrix method (2)
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- Accident causation. (1)
- Accidents analysis (1)
- Acoustical transmitter (1)
- Air-sea interaction (1)
- Atomization (1)
- Bearings (1)
- Brinkman model (1)
- Coaxial (1)
- Concrete pavement (1)
- Constrained single-layer absorber (1)
- Container handling system (1)
- Container yard (1)
- Convex condition (1)
- Cost comparison indicator (1)
- Cutting stock problem (CSP) (1)
- Cyclic triaxial test (1)
- Cylinder and planesurface (1)
- Differential quadrature method (1)
- Discontinuous conduction mode (1)
- Double-chamber muffler with extended tubes (1)
- Drilled shaft (1)
- Dynamic characteristics (1)
- Earthquake excitation (1)
- Ellipticity (1)
- Equivalent circuit (1)
Articles 1 - 30 of 33
Full-Text Articles in Engineering
Numerical Modeling For Atomization Of Coaxial Liquid/Gas Jets, Stephen Gen-Ken Chuech, Andrzej J. Przekwas, Chih-Yuan Wang
Numerical Modeling For Atomization Of Coaxial Liquid/Gas Jets, Stephen Gen-Ken Chuech, Andrzej J. Przekwas, Chih-Yuan Wang
Journal of Marine Science and Technology
In the present study, the atomization of a coaxial injector in the liquid/gas engine combustor was numerically investigated. Based on the wave instability analysis of the interface between liquid and gas, an atomization model for the high-speed liquid jets was established by coupling with the jet flow solutions. First, the wave instability was analyzed to predict the growth rates along the liquid jet surface by numerically solving the wave dispersion equation, while the governing equations of the liquid flow were solved for the formation of the liquid jet core and the variation of the liquid flow structure. Then, these two …
Steady-State Performance Of Wide Parabolic-Shaped Slider Bearings With A Couple Stress Fluid, Jaw-Ren Lin, Yu-Ming Lu
Steady-State Performance Of Wide Parabolic-Shaped Slider Bearings With A Couple Stress Fluid, Jaw-Ren Lin, Yu-Ming Lu
Journal of Marine Science and Technology
According to the Stokes micro-continuum theory, the effects of couple stresses upon the steady-state performance of wide parabolicshaped slider bearings are presented in this paper. To account for the couple stress effects arising from a Newtonian lubricant blended with various additives, the modified non-Newtonian Reynolds-type equation is derived using the Stokes motion equations together with the continuity equation. Comparing with the traditional Newtonianlubricant case, the effects of couple stresses characterized by the couple stress parameter signify an improvement in the steady-state performance. Increasing values of the couple stress parameter increases the bearing load-carrying capacity and reduces the required volume flow …
Vibration Of Simply Supported Compound Beams To Moving Loads, Jong-Dar Yau
Vibration Of Simply Supported Compound Beams To Moving Loads, Jong-Dar Yau
Journal of Marine Science and Technology
This paper is aimed at investigating the dynamic response of a compound beam subjected to moving loads at high speeds. The compound beam structure is composed of a simple beam and a twomember truss connected by a set of rigid bars at the midpoint of the beam. Based on the nonlinear elastic theory of a symmetric twomember truss under the action of a vertical tip load, and the incremental-iterative solution procedures for solving a nonlinear dynamic system, the dynamic response of the compound beam structure under the excitation of moving loads is studied. According to the numerical results, the nonlinear …
The Marine Single Assignment Nonstrict Hub Location Problem: Formulations And Experimental Examples, Shang-Hsing Hsieh, Hsien-Lun Wong
The Marine Single Assignment Nonstrict Hub Location Problem: Formulations And Experimental Examples, Shang-Hsing Hsieh, Hsien-Lun Wong
Journal of Marine Science and Technology
Marine hub-and-spoke networks have been applied to routing containerships for over two decades, but few papers have devoted their attention to these networks. The marine network problems are known as single assignment nonstrict hub location problems (SNHLPs), which deal with the optimal location of hubs and allocation of spokes to hubs in a network, allowing direct routes between some spokes. In this paper we present a satisfactory approach for solving SHNLPs. The quadratic integer profit programming consists of two-stage computational algorithms: a hub location model and a spoke allocation model. We apply a heuristic scheme based on the shortest distance …
Evaluation Of Development Strategies For Kaohsiung Port Using A Goals Achievement Method, Wen-Chih Huang
Evaluation Of Development Strategies For Kaohsiung Port Using A Goals Achievement Method, Wen-Chih Huang
Journal of Marine Science and Technology
The Port of Kaohsiung was the third largest container port in the world before 1999, although it dragged to sixth place by 2003. In order to increase the port’s competitiveness, this research outlines six goals and twenty-seven strategies from the viewpoint of international logistics. This research uses the goals achievement measurement for strategic planning effectiveness, and it was undertaken to develop the Goals Achievement Evaluation Model (GAEM) to cope with the problems of a large number of strategies and ambiguity in strategic definition. The GAEM uses a two-stage Delphi questionnaire by simplifying the quantity of responses on the survey. The …
Nonlinear Dynamic Analysis Of An Orthotropic Composite Rotor Blade, Ming-Hung Hsu
Nonlinear Dynamic Analysis Of An Orthotropic Composite Rotor Blade, Ming-Hung Hsu
Journal of Marine Science and Technology
This work presents the nonlinear dynamic analysis of orthotropic composite rotor blade using differential quadrature method (DQM). It can be found that the same efficient and procedure of DQM for both uniform composite beam and pre-twisted non-uniform composite beam. In this approach, only nine sample points are needed to achieve convergence. Dynamic responses of orthotropic composite rotor blade with various rotor rotation speeds are determined. Both linear and nonlinear dynamic responses have been obtained in order to study the significance of the nonlinear effect. The transient responses of the derived systems are calculated by using Newmark method. The bending-torsion coupled …
Nonlinear Rolling Motion Of Ship In Random Beam Seas, Jia-Yang Gu
Nonlinear Rolling Motion Of Ship In Random Beam Seas, Jia-Yang Gu
Journal of Marine Science and Technology
The highly nonlinear roll and capsizing motion of ships in random seas are analyzed in this paper by utilizing the Melnikov function and phase space flux. Influence factors on the phase space flux, such as significant wave height, significant wave frequency, nonlinear righting arm and damping characteristic, have taken into consideration. As an example, when a fishing vessel of 30.7 m long and 6.9 m wide is considered to sail in the seas of ISSC wave spectrum, the Melnikov function in time domain is computed. Also, the relation between the phase space flux and the Melnikov function has attained and …
A Hybrid Algorithm Of Evolution And Simplex Methods Applied To Global Optimization, Hsin-Chuan Kuo, Jiang-Ren Chang, Kai-Shun Shyu
A Hybrid Algorithm Of Evolution And Simplex Methods Applied To Global Optimization, Hsin-Chuan Kuo, Jiang-Ren Chang, Kai-Shun Shyu
Journal of Marine Science and Technology
In this paper, a hybrid method combining the evolution and simplex algorithms is proposed to deal with the global optimization problems of two-dimensional multi-minimum functions. Basically, the simplex method offers a search scheme without the gradient information and thus, it owns the merit of a better search speed for a local optimization problem and results in the deficiency of searching ability for the global one. In contrast, the evolution method has the better searching ability for the global problem but needs much more time. Therefore, the proposed hybrid method adopts the search technique of the simplex method and the concept …
Turbulent Film Condensation On A Horizontal Elliptical Tube With Variable Wall Temperature, Yan-Ting Lin, Sheng-An Yang
Turbulent Film Condensation On A Horizontal Elliptical Tube With Variable Wall Temperature, Yan-Ting Lin, Sheng-An Yang
Journal of Marine Science and Technology
An analytical model has been developed for the study of turbulent film condensation from downward flowing vapors onto a horizontal elliptical tube with variable wall temperature. The interfacial shear at the vapor condensate film is evaluated with the help of Colburn analogy. The condensate film flow and local/or mean heat transfer characteristics from a horizontal elliptical tube with nonuniform temperature variation under the effect of Froude number, sub-cooling parameter and system pressure parameter has been conducted. Although the non-uniform wall temperature variation has an appreciable influence on the local film flow and heat transfer; however, the dependence of mean heat …
Single And Multiple Surface Scatterings From Rough Surfaces, Chin-Yuan Hsieh, Shun-Hsyung Chang
Single And Multiple Surface Scatterings From Rough Surfaces, Chin-Yuan Hsieh, Shun-Hsyung Chang
Journal of Marine Science and Technology
The objective of this paper is to study the contributions of multiple scattering and compare it with those of the single scattering from randomly rough surfaces. The existing Kirchhoff, small perturbation and IEM scattering model cannot be used to predict the multiple scattering along the azimuth angle. In this paper we modify the IEM model by adding the phase terms in Green’s function and its derivative for multiple scattering. The function of phase term is significant to investigate the contribution of multiple scattering in the upward and downward directions. The contribution by multiple scattering is mainly based on the normalized …
Analysis Of Dynamic Characteristics For Wide Slider Bearings With An Exponential Film Profile, Jaw-Ren Lin, Chi-Ren Hung
Analysis Of Dynamic Characteristics For Wide Slider Bearings With An Exponential Film Profile, Jaw-Ren Lin, Chi-Ren Hung
Journal of Marine Science and Technology
Analysis of dynamic characteristics plays an important role in designing hydrodynamic bearings. Based upon the thin-film lubrication theory, the analysis of dynamic characteristics for a wide slider with exponential film profiles is presented when taking into account the bearing squeezing action. By applying a small perturbation technique to the dynamic Reynolds-type equation, both of the steadystate performance and the dynamic characteristics are then evaluated. Comparing with those of slider bearings with an inclined-plane film shape, higher values of the load-carrying capacity, stiffness coefficient and damping coefficient are predicted for the bearing with larger values of the inlet-outlet film ratio. These …
Tracking Control Of A Ship By Pi-Type Sliding Controller, Ker-Wei Yu, Chen-En Wu
Tracking Control Of A Ship By Pi-Type Sliding Controller, Ker-Wei Yu, Chen-En Wu
Journal of Marine Science and Technology
In this paper, the tracking control of ship maneuvering by a modified PI-type sliding controller is investigated. This scheme is composed of three components. The first component is the equivalent control, which is designed to assure that the state trajectory of the system remains in the sliding surface and the nominal system is stable in the absence of system uncertainties and disturbance. The second and third components are proportional-type and integral-type variable structure controllers, respectively. Several numerical examples of ship handling, namely course keeping, course changing, and course tracking are given to demonstrate the applicability of the proposed control scheme.
Application Of Genetic Algorithm To The Shape Optimization Of A Constrained Double-Chamber Muffler With Extended Tubes, Long-Jyi Yeh, Ying-Chun Chang, Min-Chie Chiu
Application Of Genetic Algorithm To The Shape Optimization Of A Constrained Double-Chamber Muffler With Extended Tubes, Long-Jyi Yeh, Ying-Chun Chang, Min-Chie Chiu
Journal of Marine Science and Technology
As the compact design of a muffler system within a constrained environment of a existing machine room becomes obligatory, it also becomes essential to maximize the acoustic performance of mufflers under space constraints. In this paper, the shape optimization of a double-chamber muffler with an extended tube is presented. The main characteristic of the solution methodology is the use of genetic algorithm (GA) as the optimizer. In the paper, the acoustic performance of sound transmission loss (STL) derived by transfer matrix is conjugated with the techniques of GA searching. A numerical case of noise elimination in full band noise is …
3-D Liquefaction Potential Analysis Of Seabed At Nearshore Area, Chih-Hsin Chang, Lien-Kwei Chien, Yao-Hsien Chang
3-D Liquefaction Potential Analysis Of Seabed At Nearshore Area, Chih-Hsin Chang, Lien-Kwei Chien, Yao-Hsien Chang
Journal of Marine Science and Technology
In this research, we discussed about the wave induced seabed liquefaction at nearshore based on the viewpoint of marine geotechnical engineering. The behaviors of seabed sand under wave loading were evaluated by experiments carried out in the Chien’s cyclic triaxial testing system (type II). Different loading periods, effective confining pressure and relative densities affected the liquefaction resistance of seabed sand that we sampled at northeastern coast in Taiwan. Furthermore, this study proposed the 3-D evaluation method of seabed liquefaction at Yi-Lan nearshore in case that combined the liquefaction resistance of seabed sand and Nearshore Spectral Windwave (NSW) model. The new …
A Selection Model For In-Terminal Container Handling Systems, Wen-Chih Huang, Chin-Yuan Chu
A Selection Model For In-Terminal Container Handling Systems, Wen-Chih Huang, Chin-Yuan Chu
Journal of Marine Science and Technology
This paper describes the main characteristics of in-terminal container handling systems and analyzes the factors affect the total cost of these handling technologies. A cost model is developed for decision making. It includes land cost, equipment procurement cost, maintenance cost, handling efficiency, labor cost, etc. A handling cost comparison indicator Ri/j is also proposed to make the pair comparisons between handling systems and thus to determine the most economical handling technology in the container yard. The results show that for yard cranes to be more economically operation only when procurement cost, yard size, interest rate, number of handlings per container …
Stability Analysis On The Initial Surface-Wave Generation With An Air-Sea Coupled Shear Flow, Wu-Ting Tsai, Mei-Ying Lin
Stability Analysis On The Initial Surface-Wave Generation With An Air-Sea Coupled Shear Flow, Wu-Ting Tsai, Mei-Ying Lin
Journal of Marine Science and Technology
The temporal instability of a two-dimensional perturbed wave in a coupled air-water shear flow is considered to study the generation and initial growth of wavelets by the air flow. A robust numerical method is developed to solve the coupled Orr-Sommerfeld equations and the interfacial conditions governing the linear viscous instability of the perturbed flow. Calculations of the growth rates and phase speeds of the unstable wavelets compare well with the early theoretical as well as numerical predictions, and also reveal that the discrepancy in the numerical results of Wheless and Csanady (1993) indeed are due to erroneous calculations. Dependence of …
Lump Circuit Modeling And Matching Consideration On Acoustical Transmitters For Underwater Application, Yeong-Chin Chen, Sean Wu, Cheng-Che Tsai
Lump Circuit Modeling And Matching Consideration On Acoustical Transmitters For Underwater Application, Yeong-Chin Chen, Sean Wu, Cheng-Che Tsai
Journal of Marine Science and Technology
In underwater environment the acoustical wave can transmit a long ranges away from the transmitter than the electromagnetic wave does. So far, the piezoelectric ceramic is still the best candidate as acoustical telemetry transmitters in underwater applications. The impedance matching on the interface between electro-acoustical transducer and electrical transmitter has been the most important subject to confirm the high transmitting efficiency. In this research, a lumped equivalent circuit of electro-acoustic transducer is proposed. Then, the network theorem is implemented to design a high power transformer for impedance matching, and to improve the electro-acoustic efficiency of the transducer. In the developing …
The Study On The Convex And Lmi Conditions For Static Output Feedback Stabilization, Pang-Chia Chen, Koan-Yuh Chang, Yaug-Fea Jeng, Wen-Jer Chang
The Study On The Convex And Lmi Conditions For Static Output Feedback Stabilization, Pang-Chia Chen, Koan-Yuh Chang, Yaug-Fea Jeng, Wen-Jer Chang
Journal of Marine Science and Technology
In this paper, the problem of static output feedback stabilization is considered. By congruence and state-coordinate transformations, a convex condition for static output feedback stabilization is given in terms of a matrix linear inequality while subject to an equality constraint. To facilitate stabilization design via LMI conditions, the equality constraint is satisfied by imposing a structure constraint on matrix variable. Moreover, a numerical construction algorithm and a sufficient condition for the presented convex condition are given as well. Finally, numerical examples demonstrated the utility of the proposed approach for static output feedback stabilization.
A Two-Stage Optimization Of Piece Arrangement For The Cutting Problem In Shipbuilding, Tso-Chung Sung, Wei-Chu Weng, Chien-Tung Yang
A Two-Stage Optimization Of Piece Arrangement For The Cutting Problem In Shipbuilding, Tso-Chung Sung, Wei-Chu Weng, Chien-Tung Yang
Journal of Marine Science and Technology
In this paper a two-stage optimization of piece arrangement for the cutting problem in shipbuilding is proposed. The two-stage optimization consists of a new technique, which is named as preselection and elimination technique (PSET), at the first stage and tabu search method at the second stage. Applying the new technique PSET, certain longer orders, which are chosen by a control factor, will be matched with some other shorter ones to fit the stock of shaped steel. Once these orders are selected, they will be eliminated from the whole orders. After the first stage, a tabu search approach is applied to …
A Case Study Of S-Curve Regression Method To Project Control Of Construction Management Via T-S Fuzzy Model, Ting-Ya Hsieh, Morris Hsiao-Lung Wang, Cheng-Wu Chen
A Case Study Of S-Curve Regression Method To Project Control Of Construction Management Via T-S Fuzzy Model, Ting-Ya Hsieh, Morris Hsiao-Lung Wang, Cheng-Wu Chen
Journal of Marine Science and Technology
In the contractual business, construction firms are generally more concerned with short-term financial strategies than the longterm ones. Working capital management is the central issue of all short-term financial concerns. Thus, it's urgent to study the cash portion of working capital management to rationalize the amount of cash and current assets possessed in certain time. The S-curve is quite suitable to represent the relationship between project duration and complete progress in practical usage of construction management. Based on the technique of Takagi-Sugeno (T−S) fuzzy model, the fuzzy regression model is constructed for curve fitting problems. According to the cash flow …
Numerical Optimization Of Sound Absorption Systems With Constrained Single-Layer Absorber, Ying-Chun Chang, Long-Jyi Yeh, Min-Chie Chiu, Gaung-Jer Lai
Numerical Optimization Of Sound Absorption Systems With Constrained Single-Layer Absorber, Ying-Chun Chang, Long-Jyi Yeh, Min-Chie Chiu, Gaung-Jer Lai
Journal of Marine Science and Technology
The thickness and the attached area of the sound absorber are confined in the practical engineering design while the sound absorber is applied inside the machine room to eliminate the reverberant sound energy. The optimization of the shape of the absorber and the quantification of the exact area of the absorber (in order to meet the required value of sound pressure level (SPL) at the concerned receiving point) becomes essential. For purposes stated above, two powerful gradient techniques with a logical control algorithm are applied during the optimization of the sound absorption system. Both the optimization of shape and the …
Coupled Problem Of Thermoelasticity For Multilayered Spheres With Time-Dependent Boundary Conditions, Zong-Yi Lee
Coupled Problem Of Thermoelasticity For Multilayered Spheres With Time-Dependent Boundary Conditions, Zong-Yi Lee
Journal of Marine Science and Technology
This paper deals with quasi-static coupled thermoelastic problems for multilayered spheres. Using the Laplace transform with respect to time, the general solutions of the governing equations are obtained in transform domain. The solution is obtained by using the matrix similarity transformation and inverse Laplace transform. We obtain solutions for the temperature and thermal deformation distributions for a transient state. It is demonstrated that the computational procedures established in this paper are capable of solving the generalized thermoelasticity problem of multilayered spheres.
Discontinuous Conduction Mode Of Negative Output Elementary Circuit, Jung-Chien Li, Han-Yang Chen
Discontinuous Conduction Mode Of Negative Output Elementary Circuit, Jung-Chien Li, Han-Yang Chen
Journal of Marine Science and Technology
The negative output elementary circuit operated in the discontinuous conduction mode is discussed. The voltage transfer gain of this dc-to-dc converter depends on switching frequency, conduction duty ratio, inductance, and load resistance. The condition for the discontinuous conduction mode is derived and verified. The variation ratio of the output voltage is also derived.
Optimal Pitch, Speed And Fuel Control At Sea, Thomas Hellström
Optimal Pitch, Speed And Fuel Control At Sea, Thomas Hellström
Journal of Marine Science and Technology
This paper discusses algorithms for fuel saving control for large vessels. The fuel saving is achieved by optimizing control at three levels: low level propeller and main engine control, dynamic speed control to avoid peeks in the fuel consumption and finally route planning for optimal speed profiles compensated for varying depth and weather conditions. The control problems involve classical control functions as well as numerical optimization.
Hazards Identification Model For Rail Rapid Transit Accidents, Lung-Chuang Wang
Hazards Identification Model For Rail Rapid Transit Accidents, Lung-Chuang Wang
Journal of Marine Science and Technology
In comparison with the other transportation modes, rail rapid transit already enjoys a higher degree of safety as it is designed with the exclusive right of way and the automatic train control and monitoring systems. Nevertheless, rail rapid transit systems are not free from serious accidents, which often led to human injuries and facility damages. The planning of accident prevention and emergency measures, therefore, are still important issues of the rail rapid transit operations. The model presented in this study analyses the process of hazard identification in two stages, which clearly indicate the factors of the inherent and direct hazard …
Effects Of Viscous Shear Stresses On The Squeeze Films Of Porous Parallel Rectangular Plates, Jaw-Ren Lin, Long-Jin Liang, Rong-Fang Lu
Effects Of Viscous Shear Stresses On The Squeeze Films Of Porous Parallel Rectangular Plates, Jaw-Ren Lin, Long-Jin Liang, Rong-Fang Lu
Journal of Marine Science and Technology
Considering the effects of viscous shear stresses, a study of squeeze-film behavior between porous parallel plates with finite width is presented. Based upon the Brinkman model (BM), two general coupled Reynolds equations derived for curved surfaces [20] are applied to predict the two-dimensional squeeze-film pressure and thereafter the squeeze-film characteristics. The results show that the BM predicts quite different squeeze-film behaviors to those obtained by using the slip-flow model (SFM) and the Darcy model (DM). Comparing with the SFM, the viscous shear effects provide an increase in the load-carrying capacity and lengthen the response time of finite porous squeeze-film plates. …
The Effects Of Couple Stresses In The Squeeze Film Characteristics Between A Cylinder And A Plane Surface, Jaw-Ren Lin, Won-Hsion Liao, Chi-Ren Hung
The Effects Of Couple Stresses In The Squeeze Film Characteristics Between A Cylinder And A Plane Surface, Jaw-Ren Lin, Won-Hsion Liao, Chi-Ren Hung
Journal of Marine Science and Technology
On the basis of the Stokes micro-continuum theory, the effects of couple stresses resulting from the lubricant blended with various additives upon the squeeze film behavior between a long cylinder and a plane surface are analyzed. Compared to the conventional Newtonianlubricant case, the couple stress effects characterized by the couple stress parameter signify an improvement in the squeeze film characteristics. Increasing values of the couple stress parameter increases the hydrodynamic load-carrying capacity and provides a longer time to prevent cylinder-plane surface contact. The approaching time of the cylinder in reducing the film thickness h m * = 1 to h …
Response To Comments On "A Novel Approach To Determine The Astronomical Vessel Position", Jiang-Ren Chang, Chih-Li Chen, Tien-Pen Hsu
Response To Comments On "A Novel Approach To Determine The Astronomical Vessel Position", Jiang-Ren Chang, Chih-Li Chen, Tien-Pen Hsu
Journal of Marine Science and Technology
No abstract provided.
Laterial Performance Of Drilled Shaft Considering Nonlinear Soil And Structure Material Behavior, Chao-Kuang Hsueh, San-Shyan Lin, Shuh-Gi Chern
Laterial Performance Of Drilled Shaft Considering Nonlinear Soil And Structure Material Behavior, Chao-Kuang Hsueh, San-Shyan Lin, Shuh-Gi Chern
Journal of Marine Science and Technology
In addition to nonlinear soil behavior has been assumed in conventional analytical method, performance of the laterally loaded drilled-shaft is also strongly influenced by possible concrete cracking, steel yielding, and shaft/soil separation and interaction. However, these factors are often neglected in the most of available methods and studied results. The main purpose of this paper is to investigate the importance of the above-mentioned effects on lateral performance of drilled reinforced-concrete shaft. The finite element code, ABAQUS, which is available in the three-dimensional analysis is adopted for taking into account the nonlinearity in shaft and soil materials, pilesoil interaction and nonlinear …
Effects Of Earthquake Excitation On The Strength Properties Of Newly Poured Concrete, Jen-Hui Su, Tsong Yen
Effects Of Earthquake Excitation On The Strength Properties Of Newly Poured Concrete, Jen-Hui Su, Tsong Yen
Journal of Marine Science and Technology
This study examines the 28-day strength properties of concrete under shaking, such as from an earthquake, during its strength development period. With a concrete strength of 20.59 MPa (3,000 psi), groups of concrete cylinders were made and tested on a shaking table. The peak value of ground acceleration (PGA) level of the simulated earthquake and the cylinder age are the two variables considered. The test results are as follows. If the concrete is older than three days, the earthquake excitation will not significantly reduce its 28-day strength. At younger than two days, earthquake excitation will reduce the strength of the …