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The tests were performed on 2.44 m by 2.44 m light-frame wall segments, having oriented strand-board sheathing nailed to sawn lumber framing, to determine their structural response to in-plane and out-of-plane forces applied separately or in combination. There was no evidence that simultaneous application of in-plane and out-of-plane forces negatively affects the strength of walls. However, it was found that interaction of different in-plane force components can substantially reduce strength capabilities of walls relative to when only one in-plane force component exists. Applying both in-plane tension and racking force in the ratio of 1:1 reduced the capacities of walls by 25 to 40%, with how lumber studs are connected to lumber base plates strongly influencing the absolute capacity of any wall. DOI: 10.1061/(ASCE)ST.1943-541X.0000170 CE Database subject headings: Bending; Combined loads; Frames; Wood; Nails; Shear walls; Uplifting; Structural behavior. Author keywords: Bending; Combined loads; Light-frame; Lumber; Nails; OSB; Racking; Shear-wall; Uplift; Walls; Wood.

The seismic resistance of full-scale superassemblage of precast hollow core wall units is investigated. The superassemblage consists of six prestressed concrete 1.2 m wide hollow core units. Two load-bearing of the units are tied to the foundation via unbonded vertical tendons while the other four units primarily act as 'nonstructural' cladding. The longitudinal unbonded prestressing tendons consist of regular thread-bars with an in-series portion of those bars possessing a reduced diameter to act as 'fuses.' The multipanel wall system is tested under several different conditions: in-plane quasi-static reverse cyclic loading with different sizes of fuse bars and with and without rubber block spacers and sealant between units. No structural damage occurs up to the experimental [+ or -] 4% drift limit and only minor nonstructural distress is observed at 3% drift. The overall good performance of the multipanel wall system well satisfies the requirements of an emerging seismic damage avoidance design philosophy. DOI: 10.1061/(ASCE)ST.1943-541X.0000183 CE Database subject headings: Damage; Structural design; Prestressing; Tendons; Cladding; Precasting; Walls; Seismic effects. Author keywords: Fuse bars; Damage avoidance design; Unbonded prestressing tendons; Nonstructural cladding; Multipanel precast hollow core wall.

This paper focuses on the design and performance of a very tall mechanically stabilized earth (MSE) wall. Expansion of Seattle-Tacoma International Airport called for the construction of a third runway west of the two existing runways. A significant volume of compacted earth fill was required to raise the grade as much as 50 m to meet the level of the existing airfield. Nominal 2H: 1V fill slopes were used where possible, but MSE retaining walls were used where fill slopes would have encroached into existing wetlands. Consequently a four-tier 46-m-tall MSE wall was constructed along a portion of the western edge of the embankment. Performance monitoring included strain gauge-instrumented reinforcing strips, inclinometer installations with sondex settlement rings, optical survey of the wall facing for vertical and lateral movements, and piezometers. This paper describes wall design issues, aspects associated with the instrumentation of the wall, and the observed performance. Monitoring indicates satisfactory performance of the MSE wall and compares reasonably well with predicted performance. DOI: 10.1061/(ASCE)GT.1943-5606.0000294 CE Database subject headings: Soil stabilization: Retaining walls; Performance characteristics; Instrumentation; Design; Displacement; Washington; Airport and airfield runways. Author keywords: Soil stabilization; Retaining walls; Performance; Instrumentation; Design; Displacement.

Slurry trench cutoff walls, constructed using self-hardening slag-cement-bentonite (Slag-CB), are the most common form of in-ground vertical contaminant barrier in the U.K., Europe, and Japan, and are increasingly being used in the United States. This paper presents a case study of the hydraulic conductivity evaluation of an 11-year-old Slag-CB wall material at a sulfate-contaminated site, using different in situ techniques and laboratory tests. The laboratory results suggest that the hydraulic conductivity of the samples, which vary in age from 4 weeks to 11 years, decreases with time for the first 3 years but then remains constant. The results indicate that the long-term performance of these containment walls is influenced by various parameters such as aging, the type/duration of contaminant exposure, mixing of surrounding soil during construction, and wall depth. Piezocone tests, packer tests, and self-boring permeameter tests were carried out in the field to determine the suitability of different in situ techniques and compare with the laboratory results. The hydraulic conductivity is affected by the type of in situ technique used and the geometric scale of the test section. DOI: 10.1061/(ASCE)GT. 1943-5606.0000248 CE Database subject headings: Bentonite; Cement; Containment; Groundwater pollution; Heterogeneity; Hydraulic conductivity; In situ tests; Slurry walls. Author keywords: Bentonite; Cements; Containment; Groundwater pollution; Heterogeneity; Hydraulic conductivity; In situ tests; Slurry walls.

This paper presents the results of four full-scale impact tests against barriers placed on top of an instrumented mechanically stabilized earth (MSE) wall. The impact was created by a head-on collision of a 2,268-kg bogie going at about 32.2 km/h. The barriers were New Jersey and vertical wall barriers with a 1.37-m-wide moment slab in 9.14-m-long sections. The wall was 1.52 m high with one panel and two layers of reinforcement. The reinforcement was 2.44-m-long strips, 4.88-m-long strips, and 2.44-m-long bar mats. The backfill was crushed rock. The instrumentation consisted of accelerometers, strain gauges, contact switch, displacement targets, string lines, and high-speed cameras. The test was designed to represent a commonly used installation in current practice including an impact load on the barrier at least equal to 240 kN. Most of the barriers sustained significant damage but overall the behavior of the wall was satisfactory since the displacements of the panels were minimal (less than 25 mm) and the panel damage was acceptable except possibly in the case of the 4.88-m-long strips. The loads measured in the reinforcement indicate that the reinforcement was brought to its ultimate capacity for the duration of the impact but since the impact duration was so short and since the displacements of the panels were within tolerable limits of 25 mm, this is considered acceptable. The use of the longer strips (4.88-m-long strips) leads to slightly smaller panel displacements and higher panel stresses as evidenced by a bending crack in the panel. The 2.44-m-long strips permitted more displacement of the wall panels, but the magnitude of the displacement was considered to be tolerable. The measured maximum dynamic loads in the strips were found to be 3-5 times higher than the calculated maximum static loads by AASHTO guidelines. DOI: 10.1061/(ASCE)GT.1943-5606.0000232 CE Database subject headings: Impact tests; Barriers; Highway and road structures; Pullout; Reinforcement; Walls. Author keywords: Impact text; Traffic barrier; Pullout; Reinforcement; Mechanically stabilized earthwalls.

With an inclinometer casing mounted on a sheet pile wall in peat bogs, sheet pile wall deflections were measured during a trial deep dynamic compaction (DDC) test. Analyses of the trial testing data indicated that sheet pie wall deflections were significantly affected by the tamping distance, X, (horizontal distance between tamping points and sheet pile walls). The DDC-induced wall deflections can be simulated by an exponential relationship related to X. The trial testing results were verified by the finite-element (FE) simulation. The FE analyses indicated that sheet pile wall deflections were linearly proportional to the impact energy per blow, [E.sub.i]. The analyses of surveyed data showed that sheet pile wall deflections due to DDC were also related to the ratio of the wall penetration depth in the underlying sands, [d.sub.s], to the wall height, L. Based on these findings, a semiempirical approach, incorporating the key factors that govern the sheet pile wall deflections during DDC, was developed. The estimated wall deflections using this developed method were in reasonable agreement with the field measurements. DOI: 10.1061/(ASCE)CF.1943-5509.0000059 CE Database subject headings: Deflection; Sheet piles; Walls; Empirical equations. Author keywords: Deflection; Sheet piles; Peat; DDC; Semiempirical.

Old residential buildings, such as those built before 1960, were commonly supported on cripple walls, which are walls constructed of short wooden studs between the foundation and first floor framing. For most of these old buildings, the inertial force developed by the horizontal earthquake ground motion must be resisted entirely by the cripple wall and wall-to-foundation connection. Past earthquakes in California have shown that unbraced cripple walls are particularly vulnerable due to insufficient lateral resistance, even for a moderate level of ground shaking. This paper summarizes the results of a test program conducted on level and stepped cripple walls. Specimens with details representative of current construction and retrofit were tested using displacement histories recommended for ordinary and near-fault ground motions. Key parameters of the test program included the height and slope of the cripple wall, gravity load level, stucco finish, loading history, and framing details for stepped cripple walls. Results from the test program are compared with current design values. DOI: 10.1061/(ASCE)0733-9445(2003)129:5(567) CE Database subject headings: Walls; Buildings, residential; Seismic response; California.

Researchers from the University of Florida have developed a hurricane simulator that employs an array of eight high-efficiency vane-axial fans to simulate a hurricane. This equipment can be used to mimic the effects of rain driven by a hurricane's wind to test water intrusion into walls and windows.