## 1 Introduction  
Design response spectra (DRS) and spectrum-consistent earthquakes (SCEs) are powerful tools to design earthquake-resistant structures. According to codes, static or dynamic methods of analysis may in fact be adopted to assess the seismic performance of new or existing buildings. Some such methods are based on DRS while some others apply SCEs to perform numerical analyses. Typically, static methods derive the horizontal design loads directly from the DRS, while dynamic methods may refer either to DRS or to SCEs. Seismic methods may also be linear or non-linear, depending on whether the structural material is modelled through a linear-elastic or an elastic-plastic behavior. The simplest method proposed by codes is the linear-static one, which applies a pattern of static loads proportional to the masses and to the DRS accelerations; it generally gives less accurate results [1]. The non-linear-static method (also known as Pushover Analysis) applies a pattern of increasing static loads to the structure until targeted inelastic displacement levels are reached [2]. On the other hand, linear-dynamic methods are basically two. The first one is the Modal Response Spectrum Analysis (MRSA) which combines the maximum contributions of the most significant vibration modes of a structure as taken from the DRS. It is usually assumed to be the reference method by codes [3], and is widely adopted for the seismic assessment of new and retrofitted buildings [4]. The second method is the Linear Time-History Analysis (LTHA), which directly integrates the linear differential motion equations of the system under SCEs. The most powerful code-compliant method to assess the seismic behavior of a structure is the Non-Linear Time-History Analysis (NLTHA), which is based on integrating the non-linear differential equations of motion under SCEs. This method can be applied to any kind of structure and material, leading to very useful results, e.g., [3, 5, 6]. The SCEs can be also used to perform Incremental Dynamic Analyses and to build fragility curves [7]. Since SCEs are design earthquakes which must be consistent with the DRS, all the above-mentioned methods, directly or indirectly, refer to the DRS. This means that the accurate definition of the DRS is of paramount importance both to design new earthquake-resistant buildings and to assess the seismic vulnerability of existing buildings. DRSs are provided by codes as a function of some parameters accounting for seismic hazard, geological and topographical conditions, limit states, damping ratio, behavior factors, life cycle and use categories. On the other hand, a database of recorded ground motions should be at researcher's disposal to obtain suitable suites of synthetic SCEs. Inconsistencies in codes in the definition of DRS [8, 9], as well as unavailability of suitable seismic records for the dynamic analyses are some of the obstacles that may compromise the seismic design/assessment of buildings. This kind of risk might affect the Lebanese seismic design. Crossed by an active fault which extends from the Red Sea to Turkey, Lebanon lies in an extremely important tectonic system that generated the catastrophic Kahramanmaras 2023 earthquake, mainly affecting Turkey and Syria. Lebanon introduced seismic regulations only recently [10, 11]. Such regulations mostly refer to four seismic codes of foreign countries, this leading to unclear and/or conflicting instructions for the response spectrum definition. In addition, practitioners or researchers who want to carry out time-history analyses, also face the difficulty of finding suitable records of Lebanese earthquakes [12]. On the other hand, available records relevant to earthquakes occurring along other strike-slip faults, such as the San Andreas fault, have different features and are characterized by different geological mechanisms from the earthquakes affecting the Eastern Mediterranean coastal region. Thus, referring to those records may lead to inconsistent results. This paper mainly has a twofold purpose.