دکتر محمدرضا چناقلو

Granular dampers at the foundation reduce the vibration of upper stores when the earthquake occurs. Considering that the shape of grains is one of the most important properties of granular materials that affect the mechanical behavior of granular media, therefore, in this study, the effect of particle shape on energy components has been investigated. The numerical model was analyzed by discrete element method by PFC 2D, according to the existing laboratory model and under cyclic loading. After verification, the clump element was used to simulate the grains in the three shapes of a circle representing rounded grains, a square, and a triangle representing angular grains. Finally, the combined models consisting of grains with the mentioned three shapes were used for simulation. The results indicate that in confined conditions, more than 80% of the total energy is stored as elastic strain energy or dissipated due to sliding between the particles. The contribution of kinetic and damping energies is about 10 to 15% of the total energy. Angular square-shaped particles increase the dissipated energy by damping, and triangular-shaped particles increase dissipated energy due to the sliding. In granular systems with the purpose of energy dissipation, it is better to use rounded and angular particles in equal proportions.

Due to the disadvantages of some existing connections such as the lateral-torsional buckling of RBS connections (Akbari Hamed and Basim, 2020; Akbari Hamed and Bafandeh Nobari, 2021), Saeidzadeh et al. (2022) proposed a novel partial-strength and semi-rigid (Chenaghlou and Akbari Hamed, 2017; Eurocode3, 2005) self-centering connection which eliminates residual drifts and provides more ductility in comparison with existing connections. Considering the stable cycle behavior and the advantages of this connection, in this paper, the structural cyclic behavior of this novel connection was compared with existing connections under the applied quasi-static loading. To this aim, the verified finite element models of four connections including welded moment connection (WMC), post-tensioned strand connection (PTSC), friction damper connection (FDC) and metallic yielding damper connection (MYDC) were considered.

Tensegrity systems have been used as a class of light space structures in the various forms including flat modular systems, barrel vaults and cable domes. Conventional cable domes achieve their stability through a concrete compression ring, which is inconsistent with the self-support characteristic of tensegrity systems. The previous evidences also showed that the presence of a rigid support system such as a concrete ring around the space structure especially subjected to seismic loads may cause more structural damages in boundary region of structure. In this research, the combination of a Levy-type cable dome with a tensegrity ring created by the semi-regular modules is considered, which leads to a new hybrid cable-strut system. Form-finding of the studied structures is carried out using the force density method. After designing the hybrid structure, its initial collapse behavior is evaluated by the numerical finite elements method. In this regard, static and dynamic analyses are performed on both the hybrid structure and the cable dome attached to rigid supports to evaluate the effect of the tensegrity ring on the cable dome behavior and also the adequacy of static analyses to estimate capacity of the structures. After estimating the initial behavior and the collapse mechanism type of the studied structures, their behavior, are improved by equipping a number of critical struts with Force-limiting devices.

In the present study, the effect of ice-shedding simultaneously at the transmission line's span and the wind was investigated using numerical modeling, and its results are presented. The transmission line has five transmission towers and six power transmission spans related to the 400 kV transmission line of the Khoy-Urmia power plant. The transmission tower's weaknesses have been identified using this study's results, which can be considered in strengthening existing towers and the design of new transmission lines.

In the present paper, electromechanical finite element modelling of a smart adaptive composite beam is presented. The model is formulated based on linear electromechanics and electrokinematics assumptions. The proposed model is a three layers piezoelectric composite beam that acts as transversely actuator. elastic material of core is isotropic whereas the outer piezoelectric layers is orthotropic. The accuracy of analytic and numerical models is demonstrated by examining the simulation of the two principles of mechanical and electrical energy conservation in a finite element program and also comparing its results with the ANSYS numerical model. In the numerical simulation of the finite element model, there are three mesh including 10, 50, and 100 elements. Parametric simulation consists of three mechanical, electrical and electromechanical static loading sets. By comparing the results of modeling in the finite element programming and ANSYS, and verifying the principle of electromechanical energy conservation, it can be concluded that the proposed finite element model is efficiently and accurately.

Classification of soil is a function of the geological conditions of the region, which according to the 2800 earthquake standard, is itself a function of average shear wave velocity, average standard penetration number and average undrained shear strength in cohesive soils in different layers to a depth of 30 meters from the surface. Due to the uncertainties in the mentioned parameters and also considering that the values of these parameters in the real material are not the same as the values obtained from the experimental tests, so for this and determination of these parameters requires the use of statistical and probabilistic methods. Due to the computational complexity of statistical and probabilistic methods, in this research, a fuzzy inference system has been used to the decision of the choice of soil type, which can consider uncertainties without the need for complex mathematical calculations. For this purpose, after determining the effective parameters in determining the soil type, triangular membership functions were selected for them and finally, a fuzzy inference system was designed. A comparison of the results of this study with the results of field research shows the efficiency of the proposed fuzzy inference system.

Lining of tunnels constructed using full-face tunnel boring machine consist of set of concrete segments which form a ring at each step of construction. In order to move forward, TBM inserts a great force through thrust jacks resting on segments. Installing a new ring requires decrease or elimination of jacking force. Therefore, the magnitude of force alternates as the construction continues which a part of this force remains as residual through the lining. This residual force may influence longitudinal flexural stiffness of the lining. On the other hand, time-dependent behavior of injected grout has a significant effect on the residual force. In this study first the time-dependent behavior of cement-based grout considering confining condition is investigated using the oedometer test and then modeling of staged tunnel construction and alternate loading of thrust jacks considering time-dependent grout setting is proposed using an analytical approach. In the end, residual force of lining after construction could be calculated. This approach is used to estimate the longitudinal residual force in No.1 line of Tabriz Subway Lining.

Marine structures are exposed to harsh sea environments. These structures may suffer physical damages such as collision, explosion, and chemical ones like corrosion during their exploitation. Diagnosis of damages and their repair in these important structures increase their service life. To find the damage to a structural system, it is necessary to consider its effects. According to the theory of structures, the static and dynamic responses of any structure are related to its stiffness. As a result, any sudden change in the stiffness is accompanied by a change in the static and dynamic responses of the structure; thus, it is possible to detect the probable damage in a structural system by changing its responses before and after the damage. Extreme importance of civil structures on the one hand and their expensive maintenance costs on the other hand have led researchers to strive to find more accurate and useful methods for detecting structural damage to their early stages of occurrence. In this regard, wavelet transform, which is a powerful mathematical tool for signal processing, has attracted the attention of many researchers in the field of health monitoring. In this study, based on laboratory and numerical modeling, the damage detection process in the piles of a dolphin wharf was evaluated using wavelet energy that had high sensitivity to minor changes in a vibration signal. Also, without extracting the analytical equation of the damage index, the exact location of the damage is determined directly by calculating the continuous wavelet transform energy density (Scalogram). Evaluation of the results demonstrated that the proposed method in multiple damage simulation scenarios accurately predicted the location of three damages without any additional errors. While estimating the location of damages is accompanied by error in other methods. Comparison between the results obtained from the proposed method and laboratory results demonstrates the capability of the introduced method to detect multiple damages by calculating the continuous wavelet transform energy density.

Space structures are the best solution for covering large areas with few or no intermediate supports. These structures have advantages such as light weight, delicate appearance and ease of erection. Despite these advantages, space structures suffer from progressive collapse due to buckling of compression members. In order to prevent the progressive collapse and improve the double layer space structure’s response, several mechanisms have been developed including force limiting devices (FLDs). The available FLDs have never been practically applied to space structures due to serious drawbacks. To improve the previous FLD’s performance, an innovative type of force limiting device is introduced in this study. This force limiting device which is entitled as Accordion Force Limiting Device (AFLD) is designed based on the idea of buckling restrained braces (BRB). To evaluate the efficiency of this new device, a whole steel accordion force limiting device is designed and constructed to be tested under uniaxial compressive loading. Numerical models are also developed to investigate the effect of applying AFLD on stability of double layer barrel vaults. A parametric study is carried out to study the effect of AFLD, considering Length to span ratio and rise to span ratio in double layer barrel vaults. Results indicated that applying AFLD to critical compression members improves the stability behavior noticeably.

In recent years, it is tried to express the expected performance of structures as financial and social measures. In this study, an algorithm for optimal design of viscous dampers with the goal of achieving minimum total cost is presented. For this purpose, an appropriate cost model to determine the initial cost of equipping structures with viscous dampers has been presented and the expected costs of the structure due to possible earthquakes over its life cycle have been estimated using life cycle cost analysis (LCCA). The results of this analysis have been used in an optimization algorithm with the aim of achieving minimum total cost of structures. To evaluate the seismic behavior of structures, the Endurance Time (ET) method is used as a dynamic analysis method which requires much less computation effort than conventional time history methods. In this regard, three moment frames with 3,7 and 15 stories having weakness in initial design are modeled nonlinearly, and then, using genetic algorithm the optimum arrangement of linear and nonlinear viscous dampers along with the damping exponent (Alpha) is acquired. Two closed form methods have also been used for the design of viscous dampers, namely energy-based damping design and direct displacement design. Finally, the performance of the structures has been evaluated under 12 far-field and 12 near fault ground motion records.

Nonlinear time history analysis (NL-THA) is the most accurate method to estimate the seismic demand of structures and predict their failure. To that end, extensive efforts have been made to develop fast and convenient methods to carry out nonlinear static analyses. In recent years, pushover methods have been widely used as a suitable tool to evalute the seismic performance of structures. Also, various advanced pushover procedures have been proposed to take into account the effect of higher modes and the change in the dynamic properties of structures in the nonlinear phase. Therefore, different pushover procedures have been further developed for this purpose. The nonlinear static analysis  has been widely employed to evaluate the nonlinear behavior of structures. The pushover analysis was first expanded in a number of studies to investigate buildings. Not many studies have been conducted on the seismic demand of latticed space structures. In the present work, therefore, an optimization procedure has been employed to refine the performance of the pushover analysis in estimating the seismic response of double-layer barrel vault roofs with vertical double-layer walls. In the  method proposed herein, the coefficients of the modal load combinations of the studied structures have been optimized using the simplex algorithm to find the optimum load pattern. Fifteen models with various rise-to-span and height-to-span ratios were considered to assess the accuracy of the proposed method in predicting the seismic demand of these structures. The models were analyzed using the OpenSees software. In order to model the buckling behavior of the members, each member was divided into two nonlinear beam-column elements with an initial imperfection of 0.1% at its mid-node.  The models were designed with the dead, snow, temperature, and earthquake loads having been considered. All of the mentioned loads, with the exception of snow load, were applied to the structures as concentrated nodal loads. The snow load, by contrast, was applied to the structures in two symmetric and asymmetric patterns in accordance with the sixth volume of the Iranian national code of buildings. For earthquake loads, the 4th edition of the Iranian code of practice for seismic resistant design of buildings was used. It should be noted that the seismic mass of the roof of each model was calculated by considering the entirety of the dead load in addition to 40% of the snow load. In the design process of each model, the dead, snow, temperature, and earthquake load combinations were formulated based on the AISC-ASD89 standard. The sections of the members of the structures were chosen from hollow tubular sections, with  their slenderness ratios limited to 100. Afterwards, pushover analyses were performed using the optimized load pattern. The obtained results were compared to those of the incremental dynamic analyses (IDA) and two other well-known pushover methods, namely the MPA and the conventional first-mode pushover analysis. The results revealed that the proposed pushover method can provide a good estimation of the base shear and intial stiffness of the structures when compared to dynamic analyses. In addition, an increase in the rise-to-span ratio of the roof causes an improvement in the accuracy of the proposed pushover method. Also, in comparison with the  MPA and conventional pushover procedures, the responses produced by the proposed method are closer to those generated by dynamic analyses. In addition, a comparison of the obtained drift patterns reveals that the results of both the pushover and incremental dynamic analyses along the longitudinal direction of the wall are quite close to each other. Another advantage of the proposed pushover method is that it also produces acceptable results on the nodes on the roof of the space structure. Also, along the transverse direction, the proposed method yields better results.

The quality of interior space of each building should be amenable to the life type according to which its structure has been created. Mosques as distinctive structures of Islamic Architecture, observe this princi ple, as well. The main activity occurring in the mosques, i.e. praying, has not changed during the history and their aesthetic characteristics as a funda mental concept in Islamic Architecture have always been under attention in all stages. With this back ground, this paper tries to study how Aesthetics and the quality of interior space of mosques are related and how coordination as one of the aesthetic criteria with regard to Islamic philosophy affects the quality of interior space of mosques. It seems that the rela tionship between these two concepts should be con sidered both in parts and as a whole. So the main hypothesis of this study is that “coordination affects the spirituality of interior space of mosques by influ encing the elements of space and the interaction that exists between these elements”. Since the historical mosques are the most prominent instances of Islamic art and architecture, Sheikh Lotfollah mosque is con sidered in this study. In order to determine the extent to which coordination affects the spirituality of inte rior space, 40 specialists in architecture and Islamic architecture in Tabriz, who had previously visited Sheikh Lotfollah, participated in this study. The data gathering instrument was a questionnaire, consisting of two parts. In the first part, 15 direct questions were asked in order to examine the impacts of coordination between the elements of space on the spirituality of the mosque, and in the second part, 20 indirect questions were asked to evaluate the interaction between the elements of interior space of Sheikh Lotfollah mosque. Moreover, some photos of interior space of Sheikh Lotfollah with high resolution and great quality were given to the participants along with the ques tionnaires. Then all the questionnaires were analyzed by the SPSS software and the results were discussed using qualitative methods. The results indicate that not only is there a significant relationship between coordination and the spirituality of the interior space of mosques, but also coordination significantly affects individual elements that create the spirituality of the interior space of mosques as well as the interaction that exists between these elements. It means that, individual elements cannot create the framework of a building by themselves, rather, the interaction be tween the elements and the effects they have on each other is essential in this regard.
 Considering the coordination of each element of interior space, it can be claimed that the items of ma terial and color have the most influence on the spirit uality of the space and when the interaction between the elements and their coordination is being exam ined, proportion and color have the most impact on the spirituality of the space.

N‌u‌m‌e‌r‌i‌c‌a‌l m‌o‌d‌e‌l‌i‌n‌g o‌f c‌o‌n‌c‌r‌e‌t‌e a‌r‌c‌h d‌a‌m‌s b‌y c‌o‌n‌s‌i‌d‌e‌r‌i‌n‌g d‌a‌m-r‌e‌s‌e‌r‌v‌o‌i‌r-a‌b‌u‌t‌m‌e‌n‌t i‌n‌t‌e‌r‌a‌c‌t‌i‌o‌n i‌s a c‌o‌m‌p‌l‌i‌c‌a‌t‌e‌d ‌u‌b‌j‌e‌c‌t i‌n t‌h‌e f‌i‌e‌l‌d o‌f e‌n‌g‌i‌n‌e‌e‌r‌i‌n‌g. T‌h‌i‌s c‌o‌m‌p‌l‌e‌x‌i‌t‌y i‌s d‌u‌e t‌o d‌i‌f‌f‌e‌r‌e‌n‌t f‌a‌c‌t‌o‌r‌s, s‌u‌c‌h a‌s i‌n‌t‌e‌r‌a‌c‌t‌i‌o‌n b‌e‌t‌w‌e‌e‌n d‌i‌f‌f‌e‌r‌e‌n‌t m‌e‌d‌i‌a, t‌h‌e n‌o‌n‌l‌i‌n‌e‌a‌r b‌e‌h‌a‌v‌i‌o‌r o‌f c‌o‌n‌c‌r‌e‌t‌e a‌n‌d b‌e‌d‌r‌o‌c‌k, e‌x‌p‌a‌n‌s‌i‌o‌n j‌o‌i‌n‌t‌s i‌n t‌h‌e d‌a‌m b‌o‌d‌y, f‌a‌u‌l‌t‌s a‌n‌d m‌a‌j‌o‌r j‌o‌i‌n‌t‌s i‌n t‌h‌e a‌b‌u‌t‌m‌e‌n‌t r‌o‌c‌k a‌n‌d e‌t‌c.I‌n p‌a‌s‌t y‌e‌a‌r‌s, e‌x‌t‌e‌n‌s‌i‌v‌e r‌e‌s‌e‌a‌r‌c‌h i‌n v‌a‌r‌i‌o‌u‌s f‌i‌e‌l‌d‌s r‌e‌l‌a‌t‌e‌d t‌o t‌h‌e a‌n‌a‌l‌y‌s‌i‌s a‌n‌d d‌e‌s‌i‌g‌n o‌f c‌o‌n‌c‌r‌e‌t‌e d‌a‌m‌s h‌a‌s b‌e‌e‌n u‌n‌d‌e‌r‌t‌a‌k‌e‌n, b‌u‌t t‌h‌e n‌e‌e‌d f‌o‌r m‌o‌r‌e a‌c‌c‌u‌r‌a‌t‌e m‌o‌d‌e‌l‌i‌n‌g o‌f a‌b‌u‌t‌m‌e‌n‌t‌s i‌n a c‌o‌u‌p‌l‌i‌n‌g s‌y‌s‌t‌e‌m, c‌o‌n‌s‌i‌d‌e‌r‌i‌n‌g m‌a‌s‌s, f‌l‌e‌x‌i‌b‌i‌l‌i‌t‌y a‌n‌d n‌o‌n-h‌o‌m‌o‌g‌e‌n‌e‌i‌t‌y o‌f a d‌i‌s‌c‌o‌n‌t‌i‌n‌u‌o‌u‌s r‌o‌c‌k f‌o‌u‌n‌d‌a‌t‌i‌o‌n, i‌s s‌t‌i‌l‌l r‌e‌q‌u‌i‌r‌e‌d. F‌u‌r‌t‌h‌e‌r‌m‌o‌r‌e, t‌h‌e s‌t‌r‌u‌c‌t‌u‌r‌a‌l s‌t‌r‌e‌n‌g‌t‌h o‌f a‌n a‌r‌c‌h d‌a‌m u‌n‌d‌e‌r g‌r‌o‌u‌n‌d m‌o‌t‌i‌o‌n i‌s s‌t‌r‌o‌n‌g‌l‌y d‌e‌p‌e‌n‌d‌e‌n‌t o‌n t‌h‌e s‌t‌a‌b‌i‌l‌i‌t‌y a‌n‌d s‌t‌r‌e‌n‌g‌t‌h o‌f i‌t‌s a‌b‌u‌t‌m‌e‌n‌t‌s. A‌c‌t‌u‌a‌l‌l‌y, e‌v‌e‌n h‌i‌g‌h s‌a‌f‌e‌t‌y m‌a‌r‌g‌i‌n‌s f‌o‌r u‌n‌e‌x‌p‌e‌c‌t‌e‌d g‌r‌o‌u‌n‌d m‌o‌t‌i‌o‌n d‌o n‌o‌t g‌u‌a‌r‌a‌n‌t‌e‌e t‌h‌e s‌t‌a‌b‌i‌l‌i‌t‌y o‌f a d‌a‌m i‌f i‌t i‌s e‌s‌t‌a‌b‌l‌i‌s‌h‌e‌d o‌n a‌n u‌n‌c‌e‌r‌t‌a‌i‌n f‌o‌u‌n‌d‌a‌t‌i‌o‌n.I‌n t‌h‌i‌s r‌e‌s‌e‌a‌r‌c‌h, f‌i‌n‌i‌t‌e e‌l‌e‌m‌e‌n‌t s‌o‌f‌t‌w‌a‌r‌e f‌o‌r n‌o‌n‌l‌i‌n‌e‌a‌r d‌y‌n‌a‌m‌i‌c a‌n‌a‌l‌y‌s‌i‌s o‌f c‌o‌n‌c‌r‌e‌t‌e d‌a‌m‌s i‌s d‌e‌v‌e‌l‌o‌p‌e‌d t‌h‌a‌t c‌a‌n s‌i‌m‌u‌l‌a‌t‌e t‌h‌e i‌n‌t‌e‌r‌a‌c‌t‌i‌v‌e s‌i‌t‌u‌a‌t‌i‌o‌n a‌n‌d p‌r‌e‌c‌i‌s‌e‌l‌y e‌v‌a‌l‌u‌a‌t‌e t‌h‌e d‌a‌m r‌e‌s‌p‌o‌n‌s‌e. S‌o‌m‌e f‌e‌a‌t‌u‌r‌e‌s o‌f t‌h‌e d‌e‌v‌e‌l‌o‌p‌e‌d n‌u‌m‌e‌r‌i‌c‌a‌l p‌r‌o‌g‌r‌a‌m a‌r‌e i‌t‌s a‌b‌i‌l‌i‌t‌y t‌o m‌o‌d‌e‌l w‌a‌t‌e‌r-s‌t‌r‌u‌c‌t‌u‌r‌e-r‌o‌c‌k i‌n‌t‌e‌r‌a‌c‌t‌i‌o‌n‌s, t‌h‌e n‌o‌n‌l‌i‌n‌e‌a‌r b‌e‌h‌a‌v‌i‌o‌r o‌f c‌o‌n‌c‌r‌e‌t‌e a‌n‌d a‌b‌u‌t‌m‌e‌n‌t r‌o‌c‌k, t‌h‌e c‌o‌n‌t‌a‌c‌t b‌e‌h‌a‌v‌i‌o‌r o‌f d‌a‌m e‌x‌p‌a‌n‌s‌i‌o‌n j‌o‌i‌n‌t‌s a‌n‌d f‌o‌u‌n‌d‌a‌t‌i‌o‌n d‌i‌s‌c‌o‌n‌t‌i‌n‌u‌i‌t‌i‌e‌s, a‌p‌p‌r‌o‌p‌r‌i‌a‌t‌e b‌o‌u‌n‌d‌a‌r‌y c‌o‌n‌d‌i‌t‌i‌o‌n‌s f‌o‌r t‌h‌e f‌a‌r e‌n‌d c‌u‌t o‌u‌t o‌f t‌h‌e r‌e‌s‌e‌r‌v‌o‌i‌r a‌n‌d t‌h‌e r‌o‌c‌k f‌o‌u‌n‌d‌a‌t‌i‌o‌n, a‌n‌d t‌h‌e p‌r‌o‌p‌e‌r a‌b‌u‌t‌m‌e‌n‌t i‌n-s‌i‌t‌u s‌t‌r‌e‌s‌s‌e‌s. T‌h‌e p‌r‌e‌s‌e‌n‌t s‌t‌u‌d‌y s‌e‌t‌s o‌u‌t t‌o i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e t‌h‌e n‌o‌n-l‌i‌n‌e‌a‌r s‌e‌i‌s‌m‌i‌c r‌e‌s‌p‌o‌n‌s‌e o‌f a d‌a‌m-r‌e‌s‌e‌r‌v‌o‌i‌r-f‌o‌u‌n‌d‌a‌t‌i‌o‌n s‌y‌s‌t‌e‌m, t‌a‌k‌i‌n‌g i‌n‌t‌o c‌o‌n‌s‌i‌d‌e‌r‌a‌t‌i‌o‌n t‌h‌e e‌f‌f‌e‌c‌t‌s o‌f a d‌i‌s‌c‌o‌n‌t‌i‌n‌u‌o‌u‌s r‌o‌c‌k f‌o‌u‌n‌d‌a‌t‌i‌o‌n. A‌f‌t‌e‌r v‌e‌r‌i‌f‌i‌c‌a‌t‌i‌o‌n o‌f d‌i‌f‌f‌e‌r‌e‌n‌t a‌s‌p‌e‌c‌t‌s o‌f t‌h‌e p‌r‌o‌g‌r‌a‌m, a t‌y‌p‌i‌c‌a‌l c‌a‌s‌e s‌t‌u‌d‌y o‌f a c‌o‌n‌c‌r‌e‌t‌e d‌a‌m (K‌a‌r‌u‌n 4 D‌a‌m) u‌n‌d‌e‌r s‌e‌i‌s‌m‌i‌c l‌o‌a‌d‌i‌n‌g, c‌o‌n‌s‌i‌d‌e‌r‌i‌n‌g i‌t‌s e‌f‌f‌e‌c‌t‌i‌v‌e f‌a‌c‌t‌o‌r‌s, i‌s s‌t‌u‌d‌i‌e‌d. T‌h‌e a‌n‌a‌l‌y‌s‌i‌s r‌e‌s‌u‌l‌t‌s a‌p‌p‌r‌o‌v‌e t‌h‌e i‌m‌p‌o‌r‌t‌a‌n‌c‌e a‌n‌d s‌i‌g‌n‌i‌f‌i‌c‌a‌n‌c‌e o‌f d‌i‌f‌f‌e‌r‌e‌n‌t f‌a‌c‌t‌o‌r‌s, s‌u‌c‌h a‌s m‌o‌d‌e‌l‌i‌n‌g t‌h‌e d‌i‌s‌c‌o‌n‌t‌i‌n‌u‌o‌u‌s f‌l‌e‌x‌i‌b‌l‌e m‌a‌s‌s‌i‌v‌e f‌o‌u‌n‌d‌a‌t‌i‌o‌n, a‌l‌o‌n‌g w‌i‌t‌h a‌p‌p‌r‌o‌p‌r‌i‌a‌t‌e a‌b‌s‌o‌r‌p‌t‌i‌o‌n a‌n‌d m‌o‌v‌i‌n‌g b‌o‌u‌n‌d‌a‌r‌y c‌o‌n‌d‌i‌t‌i‌o‌n‌s, o‌n t‌h‌e s‌e‌i‌s‌m‌i‌c r‌e‌s‌p‌o‌n‌s‌e o‌f d‌a‌m‌s, l‌e‌a‌d‌i‌n‌g t‌o a m‌o‌r‌e p‌r‌e‌c‌i‌s‌e d‌e‌s‌i‌g‌n o‌f n‌e‌w d‌a‌m‌s a‌n‌d b‌e‌t‌t‌e‌r c‌o‌n‌t‌r‌o‌l o‌f e‌x‌i‌s‌t‌i‌n‌g o‌n‌e‌s.