• Journal of the Earthquake Engineering Society of Korea
• /
• v.15 no.1
• /
• pp.1-10
• /
• 2011

Recently, there has been an increased interest in the noise isolation capacity of floor slabs, and thus an increase of slab thickness is required. In addition, long span floor systems are frequently used for efficient space use of building structures. In order to satisfy these requirements, a biaxial hollow slab system has been developed. To verify the structural capacity of a biaxial hollow slab system, safety verification against earthquake loads is essential. Therefore, the seismic behavior of a biaxial hollow slab system has been investigated using material nonlinear time history analyses. For efficient time history analyses, the equivalent plate element model previously proposed was used and the seismic capacity of the example structure having a biaxial hollow slab system has been evaluated using the nonlinear finite element model developed by the equivalent frame method. Based on analytical results, it has been shown that the seismic capacity of a biaxial hollow slab system is not worse than that of a flat plate slab system with the same thickness.

• Journal of Korean Association for Spatial Structures
• /
• v.5 no.1 s.15
• /
• pp.7-10
• /
• 2005

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2005.03a
• /
• pp.228-235
• /
• 2005

The floor impact sound insulations are installed frequently for reducing the floor impact sound into the floor slab of the residential buildings in recent years. Therefore the analytical FE model considering the insulations is needed for the sound and vibration analysis of the floor and it is necessary to use a refined finite element model for considering the large number of modes involving in the dynamic responses. So it is very difficult to use FE model because of the tiresome task for constructing the FE model, taking a lot of times for analysis and the impossibility of using the proportional damping. The efficient analysis and modeling method are proposed to the dynamic analysis for the floor with floor impact sound insulations in this study. The floor slabs and finished layers are modeled individually and the spring elements that mean floor impact sound insulations use to connect two parts. The dynamic analysis by the $Newmark-{\beta}$ method is performed to solve the non-proportional damping problem due to the damping coefficient of insulations .

• Journal of the Korean housing association
• /
• v.11 no.1
• /
• pp.171-181
• /
• 2000

The purpose of the resent research is to investigate the characteristics of sound insulation at the circular voided concrete slab in the multi-housing. In order to do this research, the method for field measurement of floor impact sound level was used following the Korea Standard F2810-1996. For the multi-housing, three kinds of circular voided concrete slabs are used to measure the characteristics of sound insulation.The results are as follows; 1.The main factor affecting the characteristics of sound insulation at the circular voided concrete slab in the multi-housing is sound-absorbing materials in the circular tube. 2. The main factor to effect the difference of sound pressure level is circular tube in the concrete slab. 3. The forms of circular tubes effect the characteristics of sound insulation at the circular tube. 4. Sound Pressure Level resulting from the piping direction of circular tubes in little different to octave band level.More study will be needed about the depth and distance of sound insulation materials, and the components of sound insulation materials for the multi-housing.

• Journal of the Korean Institute of Educational Facilities
• /
• v.26 no.2
• /
• pp.3-10
• /
• 2019

This study evaluated the vibration use and safety of students living in the dormitories on the 12th and 14th floors by feeling uncomfortable. The measurement method was to measure the acceleration due to free vibration and single - person walking. The slab stiffness was then calculated, and the usability and safety were compared according to international standards. The natural frequency of the slab was 6.8 Hz. The natural frequency of a typical slab is around 15Hz. Therefore, the evaluation slab is judged as a flexible floor structure. It is considered that there is a high possibility of resonance in the middle of daily life because of low natural frequency and near harmonic component of walking vibration. As a result, the RMS acceleration level is within the tolerance range defined by ISO 10137 code, but the 13th floor exceeds the reference limit, so that a sensitive person could detect the vibration somewhat in the lying position.

• Journal of KSNVE
• /
• v.2 no.1
• /
• pp.21-31
• /
• 1992

In the previous paper, we report a practical floor impact sound level prediction method for a heavyweight impact source(Tire), soft impact source such as children jumping and running. According to these results, the calculated value and the measured value correspond comparatively well, regardless of differences in the floor structures. And the floor impact sound for a heavyweight impact source, soft source was strongly influenced by structural factors such as floor slab stiffness and peripheral support conditions. But the floor impact sound for a light impact source (Tapping machine), hard impact source was influenced by resilient layers, composed of multi-layer in floor structures. Thus, In this paper, 4 actual floor structures, all with differing resilient layers, were calculated using impedance method. When these calculation values were compared with the measured values, approximately all the values fell with one rank of the sound insulation grade, reference curve(L curve) by the JIS standard. So, a sample of measured values and calculated values from floor structures is presented to show the accuracy and appropriateness of the impedance method in domestic.

• Journal of the Korean Society of Industry Convergence
• /
• v.7 no.4
• /
• pp.331-340
• /
• 2004

This paper presents a feasibility study of a fresh air load reduction system by using an underground double floor space. The fresh air is introduced into the double slab space and passes through the opening bored into the footing beam. The air is cooled by the heat exchange with the inside surface of the double slab space in summer, and heated in winter. This system not only reduces sensible heat load of the fresh air by heat exchange with earth but also reduces latent heat load of the fresh air by ad/de-sorption of underground double slab concrete. In this paper, we used a model for evaluation of fresh air latent heat load reduction by hygroscopic of air to earth exchange system taking into account coupled heat and moisture transfer of underground double floor space. In conclusion it shows the validity of the proposed method for a design tool and the quantitative effect of the system.

• Journal of Korean Society of Steel Construction
• /
• v.14 no.4
• /
• pp.549-556
• /
• 2002

The natural frequency of a system is commonly used in evaluating the serviceability condition of a floor. However. the current equations recommended in many building codes do not consider the various material types of a slab system; thus. different results are observed. Likewise. the transformation of a slab section required to predict the natural frequency of a composite deck plate is complicated. due to the varying shapes of the deck plates. Therefore. a new and simplified method of transforming a composite slab into an equivalent concrete slab is proposed. he modified vibration prediction equation was proposed based on the current vibration prediction equation recommended by LRFD. Compared to other equations. it is the closest to those obtained from experiments. The modified equation provides about 14.3% more accurate results than that recommended by LRFD. Likewise. the applicability of the proposed equation to other types of composite deck plate floor system was validated.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.12
• /
• pp.159-166
• /
• 2001

Recently, high story apartments are common to solve a housing problem especially in major cities. Apartments are considered as clean, sanitary and convenient to live. However, There are some problems because residents share walls, floors and ceilings with other people. Thus, the residents are often disturbed by neighbours since sound travels the building elements. Especially, impact noise through the floors causes the many complains. And so, it has been drawn attention to isolate by the impact sound. The purpose of this study is to analyze the characteristics of vibration response of 12-type void slabs in the improved void slab by impedance method, and is to find the best improveds void slab on the 12-type void slabs.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.8 no.3
• /
• pp.317-329
• /
• 1996

By describing the floor slab of a radiant heating system as a one dimensional transient heat exchanger problem, a dynamic analysis model to incorperate with TRNSYS program was developed and their results were compared with experimental results. Results showed that the both of TPOC(Two Parameter On-off Control) and TPSC(Two Parameter Switching Control) method using room air temperature and floor surface temperature as the control parameters does not maintain room air and floor surface temperature exactly at the setting temperatures. But TPSC method is a better candidate for the temperature regulations of room air and floor surface temperature than TPOC method which can keep on the upper and lower limit temperature according to outside temeperature and wall structure etc. And better thermal circumstance can be given by TPSC method than On-off and TPOC method and the overheating which can be occured at the radiant floor heating system with on-off heating control will be reduced.