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Warren Jackson- B1215 Screen Grid Test 004.jpg Page 1 j 1110,1 SUMMARY AND CONCLUSIONS In-plane lateral load tests were conducted on five wall panel specimens with an aspect ratio (height/length)of 2.The panels represented some of the typical wall systems being used for construction of residential buildings.These were a wood-frame wail panel,a steel-frame wall panel,and three ICF wall panels.One flat,one screen-grid,and one waffle-grid ICF wall panel were tested.The structural details for the test specimens were adopted from the design recommendations and guidelines for a typical exterior wall panel in the earthquake zone I or 2, with a minimum wind speed of up to 70 miles per hour.The test setup and procedure followed general guidelines of ASTM E564-95,Standard Practice for Static Load Test for Shear Resistance of Framed Walls for Buildings.Necessary modifications were applied to the test procedure to better serve the objectives of this study. The tests resulted in important information about the strength,stiffness,and failure patterns of the wall systems tested.The results indicated that,wider similar restraint conditions,ICF wall panels are much stronger and stiffer than similar wood-or steel-frame walls panels.The ICF wall panels resisted a maximum lateral load of about 6 to 8.5 times the corresponding maximum loads resisted by the framed wall panels.The initial stiffness of the ICF wall panels was between 18 and 38 times the initial stiffness of the wood-or steel-forme wall panels.Under lateral loads of about twice as much as the maximum resistance of the framed walls,the ICF panels behaved linearly,showing no damage of any sort.The deformations under this level of loads were extremely small and were in the range of 0.05 to 0.07 ion However,the maximum deflection provided by the ICF wall panels equaled or exceeded about 2%of the story height The failure of the wood-frame wall panel was dominated by the crushing and bulging/buckling of thir the OSB in the leeward bottom corner,and with the pull-out of the nails connecting the board to the frame members.In the steel-frame wall panel,the failure was governed by the OSB in the same manner as in the wood-frame panel,and with the local and global buckling/bending of the steel studs.The ICE flat wall panel failed in a flexural mode by separation of the wall from the footing in the windward side and crushing of the concrete in the leeward toe.The failure of ICF screen-grid and waffle-grid wall panels involved a shear failure in the form of an inclined crack in the lower I/3 of the wall. These results suggest that when subjected to lateral in-plane loading from sources such as wind or earthquake,ICE wall panels are not only considerably stronger,but also much stiffer than framed wall panels.The higher strength of ICE wall panels reinforces a residential building's ability to resist winds and earthquakes of much higher magnitudes.The higher stiffness of ICF wall panels limits lateral deformation and prevents potential damage to non-structural elements in buildings.In the case of moderate earthquakes(or winds),repair of damaged non-structural components is usually the major(or the only)part of restoration costs.It should he pointed out that the connections between wall panels and footings,and more importantly,between panels and roofs/floors can strongly influence the behavior of wall panels.The lack of well-designed and adequate connections can interrupt the development of an efficient load transfer mechanism between the structural members and could result in early collapse,even when the wall panels are favorably strong.Further,the positioning of the wall panels in a building plan and roof floor diaphragm action can significantly influence the lateral load distribution to the wall panels. t2