This paper presents the results of an experimental campaign investigating the seismic behaviour of full-size cross laminated timber (CLT) wall systems with sound-insulated shear-tension angle ...brackets. The main aim of the study was to investigate the influence of more and less flexible soundproofing bedding under the CLT wall. The paper shows a comparison of lateral load-bearing capacity, displacement capacity, ductility and stiffness obtained from racking tests on uninsulated specimens and specimens with various types of bedding insulation and levels of vertical load. Moreover, an analytical procedure to estimate the lateral load-displacement response of CLT walls with bedding insulation is proposed. This model is verified by direct comparison to the experimentally determined lateral load-displacement backbone curves. The results show that the elastomeric bedding does not have a significant effect on the bearing capacity of the wall system tested, but it reduces the stiffness and increases the displacement capacity. Due to the large decrease in stiffness, the insulation causes an overall reduction in ductility. The analytical estimation proposed was able to capture the reduction in lateral stiffness and adequately predict the load-bearing capacity.
•Monotonic and cyclic shear tests of walls, analytical model.•The insulation does not significantly influence the lateral load-bearing capacity.•The insulation reduces the lateral stiffness of the wall and overall ductility.•High vertical load can cause irreversible deformation of the CLT slab and insulation.•The analytical model adequately predicted the lateral load displacement response.
This paper presents results from quasi-static racking tests on gypsum wallboard sheathed light gage metal stud partition walls used in buildings. Eight nearly identical pairs of specimens were ...constructed following common United States practice. Each specimen consisted of a 4.88m long and 2.44m tall web wall and two return walls each 1.2m long and 2.44m tall. The main variables were (i) the configuration of the specimen, (ii) the spacing of wallboard-light gage stud self-tapping screws, (iii) the stud thickness and spacing, (iv) the presence of a vertically slotted track at the top of the partition wall, and (v) the wallboard thickness.
Several studies based on structural properties of plywood walls and wooden semi-rigid frames have been conducted. However, the complex behavior of a wooden semi-rigid frame composited with structural ...plywood has made it difficult to establish its structural design method. The wooden semi-rigid frame joint has the problem of displaying semi-rigid performance. Therefore, it is difficult to satisfy the necessary stiffness of 1/120 radian, which is the limit value of the deformation angle in the elastic design of buildings. In this case, it is possible to compensate for the initial stiffness by incorporating a structural wall into a wooden semi-rigid frame. In general, an independent wall framework is set up within a wooden semi-rigid frame. A plywood board is nailed onto this framework. If it can be nailed directly onto the columns of the semi-rigid frame, there is no need to place a post in the framework, and the designing process can be more cost-effective. Due to the complex behavior of the wooden semi-rigid frame composited with structural plywood, the structural design method cannot be established. This study aims to clarify the properties of the wooden semi-rigid frame with structural plywood with tests and build its structural design method. A wooden semi-rigid frame with a lag-screw-bolt (LSB) for the joints was used in this study. The structural properties of the semi-rigid frame with structural plywood were estimated by conducting static racking tests for four types of specimens. The four types of specimens were as follows: “Rigid” wooden semi-rigid frame; “Outside” wooden semi-rigid frame with a structural plywood wall nailed on the outside edge of the column; “Inside” wooden semi-rigid frame with a structural plywood wall nailed on the inside of the column; and “Wall-O” and “Wall-I” structural plywood wall only. Nuts were used to fill the empty 20 mm. The structural models of these specimens were simplified. At the bottom of each LSB, load cells were installed to measure the tension side axial force. We examined the following: the shear-rotational angle curves of the wooden semi-rigid frame of “Outside”, where “Inside” was determined from the supporting point reaction; the shear-rotational angle curves of the plywood wall of “Outside”, where “Inside” was found by taking the load-rotational angle curves of “Wall-O” or “Wall-I”. The tests showed that there is a certain difference in the shear-rotational angle curves subjected to the nail position.
In recent years, Japanese exposed-post and beam style rooms made with panels nailed onto wooden framework structures, or Menzai-Shin-Kabe, have become more common than the traditional mud plaster on ...laths method, called Tsuchi-kabe. Menzai-Shin-Kabe is the method of nailing sheathing materials, such as structural plywood, onto studs placed in between exposed-post framework. The formulae to calculate the elastic stiffness, yield point, ultimate strength and the ductility factor of Menzai-Shin-Kabe have been derived from the elements of the shear resistance of the nails hammered into the studs and bedding frames, and the truss effect from the diagonal compression resistance of the sheathing material. In order to verify the scope of application of the formulae, shear racking tests of sheathed walls have been carried out where plywood is employed as the sheathing material.
Generally in Japanese style rooms, sheathed walls with uncovered post have widely been used instead of mud walls. The sheathing material is nailed and inserted in the frame with noggins. The formula ...to calculate the elastic strength, yield point, ultimate strength and the ductility factor has been derived for the sheathed wall, considering the elements of the shear resistance of the nail strucked in the noggins and frame, and the diagonal compression resistance of the sheathing material as truss action. In order to verify the formula, the shear racking tests of sheathed walls have been carried out where plywood and plasterboard have been used as sheathing materials. It is clear that the formula is sufficiently accurate to predict the elastic and plastic behavior of sheathed walls with uncovered post for structural calculation.
A new type of moment resisting timber joint has been developed. The joint is made up of steel plates, bolts and cotters. The plates and the bolts are embedded with timber element of frame structure. ...By combining those elements with steel cotters, moment resisting joints can be constructed easily. Static loading tests of the joint have been performed, and results of the tests made it clear that the joint have rotational rigidity and strength required from constructing moment resisting joint. In this report, three kinds of racking tests were performed to simulate the moment-rotational angle. “A tests” were prototypes, and “B tests” and “C tests” had each kinds of joint. The simulation results of moment-rotational angle curves by three kinds of tests agree with the prototype tests results.
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