• KIEAE Journal
• /
• 제7권3호
• /
• pp.89-96
• /
• 2007

The purpose of this experimental study is to investigate the compressive strength, shear strength, bending strength, and crack control by the mixture of the hwang-toh. The size of compressive specimens is $200{\times}200{\times}400(mm)$, and the size of shear, bending specimens is $200{\times}200{\times}600(mm)$. Finally, crack control specimens for comparative comparison is $200{\times}200{\times}15(mm)$. The mixture of the hwang-toh is as follows; Hwangtoh( H)+Water(W), H+W+Sand(S), H+W+S+sTraw(0.5%), H+W+S+sT(1.0%). The actual height, width, and the length are measured at the center of all specimens. The main parameters are mixture ratio of hwang-toh, straw and age of specimens. The test results are as follows. (1) The compressive strength is linearly increased until 15 weeks according to specimen ages. (2) About crack control, the specimen added in 1% straw is the most effective.

• Steel and Composite Structures
• /
• 제48권6호
• /
• pp.667-679
• /
• 2023

Concrete filled rectangular steel tubular (CFRST) composite truss girder is composed of the CFRST truss and concrete slab. The failure mechanism of the girder was different under bending and shear failure modes. The bending and shear strength of the girder were investigated experimentally. The influences of composite effect and shear to span ratio on failure modes of the girder was studied. Results indicated that the top chord and the joint of the truss were strengthened by the composited effect. The failure modes of the specimens were changed from the joint on top chord to the bottom chord. However, the composite effect had limited effect on the failure modes of the girder with small shear to span ratio. The concrete slab and top chord can be regarded as the composite top chord. In this case, the axial force distribution of the girder was close to the pin-jointed truss model. An approach of strength prediction was proposed which can take the composite effect and shear to span ratio into account. The approach gave accurate predictions on the strength of CFRST composite truss girder under different bending and shear failure modes.

• 한국건축시공학회지
• /
• 제12권5호
• /
• pp.539-547
• /
• 2012

To manufacture laminated wood with improved mechanical properties by providing uniform adhesiveness, the adhesive was applied and the plate adhesive was laminated on the wood surface. Then, after laminating the wood on the top part of the adhesivebond, it was heated and dried while the adhesive was stiffened using microwaves, and the test piece was manufactured by compressing it with the press machine for thirty minutes. The temperature and the water content were examined according to the heating time of the wood heated with the microwave, and testing was conducted on the shear strength and flexural strength of the wood. In addition, the microstructure of the adhesive bond between the wood was recorded to confirm the penetrabilityinto the wood structure for the adhesive. After the test was conducted, it was found that the test piece manufactured with wood that has its water content leveled with the microwave heating showed improved shear strength and bending strength compared to the standard test piece. With regard to adhesives, liquefied polyvinyl acetate resin and plate's PVB resin were found to have superior adhesive strength. Also, after filming the cellular microstructure, it was found that when the laminated wood is heated with microwaves, the infiltration of the adhesive into the inside of the wood becomes easy, which makes it effective for improving adhesiveness.

• 한국구조물진단유지관리공학회 논문집
• /
• 제5권4호
• /
• pp.131-138
• /
• 2001

In inverted T-shape composite beam examine the structural behavior by experiment According to arrangement, type of stud connector, type of shear connector, reinforcement by welding of stirrup and a close analysis we came to these conclusion. 1) The compare result of bending strength according to arrange type of stud connector : A1-W(stud connector located web)specimen is exceed than A1-F(stud connector located flange). 2) B1-N(using prominence and depression of the web by shear connector) specimen is decrease than A1-W(using stud bolt by shear connector)specimen in bending strength and B2-N(reinforced by welding the stirrup to lower flange)specimen is similar with A2-W specimen. 3) According to reinforced by welding the stirrup to flange, the stiffness and bending strength of the beams are increase. A-scries stirrup comparatively low effective in the increase of strength by welding the stirrup to flange because enough composite effect show by stud connector, but B-series stirrup is comparatively high effective in shear connector effect because shortage of prominence and depression of the web.

• Steel and Composite Structures
• /
• 제10권5호
• /
• pp.457-473
• /
• 2010

In this study, specimens were made with profile thicknesses and shear reinforcement as parameters. The bending and shear behavior were checked, and comparative analysis was conducted of the results and the theoretical values in order to see the applicability of T-section Modular Composite Profiled Beams (TMPB). In TMPB, the profiles of formwork functions play a structural role resisting the load. Also, the module concept, which is introduced into TMPB, has advantages: it can be mass-produced in a factory, it is lighter than an existing H-beam, it can be fabricated on the spot, and its section size is freely adjustable. The T1 specimens exhibited ductile behavior, where the whole section displayed strain corresponding to yielding strain at least without separation between modules. They also exhibited maximum strength similar to the theoretical values even if shear reinforcement was not applied, due to the marginal difference between shear strength and maximum bending monment of the concrete section. A slip between modules was incurred by shear failure of the bolts in all specimens, excluding the T1 specimen, and therefore bending moment could not be fully displayed.

• 콘크리트학회논문집
• /
• 제14권6호
• /
• pp.910-921
• /
• 2002

철근콘크리트 보의 전단거동을 예측하기 위하여 휨모멘트가 고려된 변환각 트러스 모델(TATM)을 제안하였다. 제안된 TATM으로 구한 전단응력-전단변형률 관계는 본 연구에서 수행된 실험결과와 잘 일치하였다. 또한, TATM으로 구한 전단강도는 다양한 전단스팬비와 지점형태 및 단면형태를 가지는 총 170개 실험결과와 비교되었다. TATM에 의한 해석결과는 평균 0.96, 변동계수 11.9 %로서 기존의 트러스 모델에 의한 해석결과보다 실험결과를 더 잘 예측하였으며, 해석결과에 대한 실험결과의 비는 a/d와 η에 관계없이 거의 일정하였다.

• Journal of Welding and Joining
• /
• 제19권1호
• /
• pp.112-117
• /
• 2001

The factor affecting on the fatigue strength of spot welded specimen have been studied. To analyze and predict crack initiation position and propagation directions on the spot welded area are very important for strength design of the automobile body structure. In fact, there are a various of loads in running automobile but, it is impossible to replay like an actual conditions in the laboratory. So, in this study tensile-shear type and in-plane bending type specimens were used in fatigue test and includes an analysis of fatigue crack initiation position and propagation directions about earth specimens. The results obtained in the present study are summarized as follows: 1. In tensile-shear type fatigue test, the region of fatigue crack initiation position was affected by out-of-plane bending deformation due to bending angle. 2 In in-plane bending type fatigue test, the behavior of fatigue crack initiation position and propagation derections due to angle between upper plate and lower plate was dominated by magnitude of in-plane bending moment.

• Earthquakes and Structures
• /
• 제20권4호
• /
• pp.431-444
• /
• 2021

T-shaped column is usually used as side column in buildings, which is one of the weak members in structural system. This paper presented a quasi-static cyclic loading experiment of six specimens of reinforced concrete (RC) T-shaped columns under compression-flexure-shear-torsion combined loadings to investigate the effect in the ratio of torsion to moment (T/M) and axial compression ratio (n) and height-thickness ratio of flange plate (φ) on their seismic performance. Based on the test results, the failure characteristics, hysteretic curves, ductility, energy dissipation, stiffness degradation and strength degradation were analyzed. The results show that the failure characteristics of RC T-shaped columns mainly depend on the ratio of torsion to moment, which can be divided into bending failure, bending-torsion failure and shear-torsion failure. With the increase of T/M ratio, the torsion ductility coefficient increased, and in a suitable range, the torsion and horizontal displacement ductility coefficient of RC T-shaped columns could be effectively improved with the increase of axial compression ratio and the decrease of height-thickness ratio of flange plate. Besides, the energy dissipation capacity of the specimens mainly depended on the bending and shear energy dissipation capacity. On the other hand, the increase of axial compression ratio and the ratio of torsion to moment could accelerate the torsional and bending stiffness degradation of RC T-shaped columns. Moreover, the degradation coefficient of torsion strength was between 0.80 and 0.98, and that of bending strength was between 0.75 and 1.00.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.688-693
• /
• 2002

Adhesive bonding is becoming one of the popular joining techniques in metal industries, since it has some advantages over other techniques such as welding and diffusion bonding, e.g., any dissimilar metals are easily adhesive-bonded together. In this study, the experiments were carried out in order to provide the statistical data with strength evaluation methods: tension, shear and four-point bending tests for thermoplastic epoxy resin based adhesive-bonded metal joints. We should certificate on the probability of the adhesive strength that has the tendency of brittle fracture, the adhesive bonding strength between metals with thermoplastic adhesive has the best probability at four-point bending test. The strength testing method that has higher probability is four-point bending test, shear test and tensile test in order.

• Journal of the Korean Wood Science and Technology
• /
• 제38권2호
• /
• pp.94-100
• /
• 2010

This study was performed to develop an LRFD (Load Resistance Factored Design) Code for Domestic Larch. To accomplish his, we evaluated bending, compression, tension and shear strength. The results of the strength evaluation were utilized to verify the distribution and code conversion. For bending, tension and compressive strength, the Weibull distribution was well-fitted, but for shear strength we observed a normal distribution. For evaluating the bending and compressive strength, a full-sized specimen was used. A small clear specimen was used to test tension and shear strength. Compressive strength in particular was found to be affected by tight knots, although there was little difference between grades. In the code conversion, the design value of the LRFD was larger than the existing allowable stress value in the Korean Building Code. However, the allowable stress in this study was about two times higher than the value listed in the Korean Building Code. This result induced the difference between the soft and hard conversions. For greater reliability, the accumulation of additional data is necessary and further studies should be performed