This thesis presents the findings of a physical modeling study examining the hydraulic characteristics within the inlet region of a corrugated steel pipe (CSP) culvert with common inlet treatments. Also examined are the effects of embedding the culvert below the stream bed and backfilling the culvert with granular material. Velocity and turbulence distributions were examined in an effort to better understand how these inlet treatments may affect fish passage. The velocity field of each inlet configuration was dominated by a central jet of high velocity surrounded by low velocity boundary areas. Based on percent area analysis the various projecting end inlet configura-tions presented the largest area with streamwise velocities less than Uavg. The usefulness of the low velocity boundary areas may be limited by significant vertical and spanwise velocities and associated elevated turbulence levels.

This thesis presents the findings of a physical modeling study examining the hydraulic characteristics within the inlet region of a corrugated steel pipe (CSP) culvert with common inlet treatments. Also examined are the effects of embedding the culvert below the stream bed and backfilling the culvert with granular material. Velocity and turbulence distributions were examined in an effort to better understand how these inlet treatments may affect fish passage. The velocity field of each inlet configuration was dominated by a central jet of high velocity surrounded by low velocity boundary areas. Based on percent area analysis the various projecting end inlet configura-tions presented the largest area with streamwise velocities less than Uavg. The usefulness of the low velocity boundary areas may be limited by significant vertical and spanwise velocities and associated elevated turbulence levels.

Corrugated steel pipe (CSP) culverts are widely used as an economical alternative for conveying streams and small rivers through road embankments. While passage of the design flow is generally the primary goal for culvert design, consideration must also be given to maintaining connectivity within the aquatic environment for fish and other aquatic organisms. In Canada, the design criteria for fish passage through culverts are generally specified in terms of a maximum mean flow velocity corresponding to the weakest swimming fish expected to be found at a specific location. Studies have shown, however, that the velocity distribution within a CSP culvert may provide sufficient areas of lower velocity flow near the culvert boundary to allow for fish passage, even when the mean flow velocity may exceed a fishs swimming ability. Improved knowledge of the hydraulic conditions within CSP culverts, combined with research into fish swimming capabilities and preferences, may make it possible to better tailor culvert designs for fish passage while at the same time decreasing construction costs. To meet the requirements of regulators, various measures may be taken to reduce culvert flow velocities. Embedding, or setting the invert of a culvert below the normal stream bed elevation, is a simple and inexpensive method of increasing the flow area in a culvert flowing partially full, thereby decreasing flow velocity. Fish traversing through an embedded culvert benefit not only in terms of lower mean flow velocities, but also even lower flow velocities in the near boundary region. In the province of Saskatchewan culvert embedment is regularly used as a means to improve fish passage conditions. In this study, a laboratory scale model was used to study the velocity distribution within a non-embedded and embedded CSP culvert. An acoustic Doppler velocimeter was used to measure point velocities throughout the flow cross section at several longitudinal locations along the culvert. The hydraulic conditions were varied by changing the discharge, culvert slope and depth of embedment. The point velocity data were analyzed to determine patterns of velocity and turbulence intensity at each cross section, as well as along the length of the culvert. The results from the embedded culvert tests were compared with the results from the equivalent non-embedded tests, so that initial conclusions could be made regarding the use of embedment to improve conditions for fish passage. Analysis of the cross section velocity distributions showed that, even the non-embedded culvert had a significant portion of the flow area with flow velocity less than the mean velocity. The results from the embedded tests confirmed that embedding the culvert reduced the flow velocity throughout each cross section, although the effect was most significant for the cross sections located greater than one culvert diameter downstream from the inlet. This variation in effectiveness of embedment at reducing flow velocities is attributed to the length of the M1 backwater profile relative to the culvert length, and thus the differential increase in flow depth that occurred at each measurement location along the culvert. For both the non-embedded and embedded culvert the peak point magnitudes of turbulence intensity were found to be located near the culvert inlet where the flow was contracting. In terms of the cross section average turbulence intensity, in the non-embedded culvert turbulence increased with distance downstream from the inlet and was highest at the cross sections located near the culvert outlet. Embedding the culvert was found to either have no impact, or to slightly increase, the cross section average turbulence intensity near the inlet. Again, a result that is attributed to the tapering out of the M1 backwater profile at locations near the inlet under the flow conditions tested. However, beyond eight culvert diameters downstream from the inlet, embedment did result in lower cross section average turbulence intensity when compared to the non-embedded culvert. The measured velocity profiles for the non-embedded tests were found to compare well to the theoretical log-law velocity distribution using a ks value of between 0.012 m and 0.022 m, or approximately one to two times the corrugation amplitude, when the datum for analysis was considered to be located at the crest of the pipe corrugation. The cross section velocity distributions for the non-embedded tests compared very well to the model proposed by Ead et al. (2000). Based on this assessment, it appears that the Ead et al. model is potentially suitable for use in predicting the amount of the cross sectional area in a non-embedded culvert with flow velocity less than the design target for culvert fish passage design purposes. Overall, the results of the study confirm that, embedding a CSP culvert may be an effective way to improve fish passage conditions in terms of both flow velocity and turbulence intensity.

Corrugated steel pipe (CSP) culverts are widely used as an economical alternative for conveying streams and small rivers through road embankments. While passage of the design flow is generally the primary goal for culvert design, consideration must also be given to maintaining connectivity within the aquatic environment for fish and other aquatic organisms. In Canada, the design criteria for fish passage through culverts are generally specified in terms of a maximum mean flow velocity corresponding to the weakest swimming fish expected to be found at a specific location. Studies have shown, however, that the velocity distribution within a CSP culvert may provide sufficient areas of lower velocity flow near the culvert boundary to allow for fish passage, even when the mean flow velocity may exceed a fishs swimming ability. Improved knowledge of the hydraulic conditions within CSP culverts, combined with research into fish swimming capabilities and preferences, may make it possible to better tailor culvert designs for fish passage while at the same time decreasing construction costs. To meet the requirements of regulators, various measures may be taken to reduce culvert flow velocities. Embedding, or setting the invert of a culvert below the normal stream bed elevation, is a simple and inexpensive method of increasing the flow area in a culvert flowing partially full, thereby decreasing flow velocity. Fish traversing through an embedded culvert benefit not only in terms of lower mean flow velocities, but also even lower flow velocities in the near boundary region. In the province of Saskatchewan culvert embedment is regularly used as a means to improve fish passage conditions. In this study, a laboratory scale model was used to study the velocity distribution within a non-embedded and embedded CSP culvert. An acoustic Doppler velocimeter was used to measure point velocities throughout the flow cross section at several longitudinal locations along the culvert. The hydraulic conditions were varied by changing the discharge, culvert slope and depth of embedment. The point velocity data were analyzed to determine patterns of velocity and turbulence intensity at each cross section, as well as along the length of the culvert. The results from the embedded culvert tests were compared with the results from the equivalent non-embedded tests, so that initial conclusions could be made regarding the use of embedment to improve conditions for fish passage. Analysis of the cross section velocity distributions showed that, even the non-embedded culvert had a significant portion of the flow area with flow velocity less than the mean velocity. The results from the embedded tests confirmed that embedding the culvert reduced the flow velocity throughout each cross section, although the effect was most significant for the cross sections located greater than one culvert diameter downstream from the inlet. This variation in effectiveness of embedment at reducing flow velocities is attributed to the length of the M1 backwater profile relative to the culvert length, and thus the differential increase in flow depth that occurred at each measurement location along the culvert. For both the non-embedded and embedded culvert the peak point magnitudes of turbulence intensity were found to be located near the culvert inlet where the flow was contracting. In terms of the cross section average turbulence intensity, in the non-embedded culvert turbulence increased with distance downstream from the inlet and was highest at the cross sections located near the culvert outlet. Embedding the culvert was found to either have no impact, or to slightly increase, the cross section average turbulence intensity near the inlet. Again, a result that is attributed to the tapering out of the M1 backwater profile at locations near the inlet under the flow conditions tested. However, beyond eight culvert diameters downstream from the inlet, embedment did result in lower cross section average turbulence intensity when compared to the non-embedded culvert. The measured velocity profiles for the non-embedded tests were found to compare well to the theoretical log-law velocity distribution using a ks value of between 0.012 m and 0.022 m, or approximately one to two times the corrugation amplitude, when the datum for analysis was considered to be located at the crest of the pipe corrugation. The cross section velocity distributions for the non-embedded tests compared very well to the model proposed by Ead et al. (2000). Based on this assessment, it appears that the Ead et al. model is potentially suitable for use in predicting the amount of the cross sectional area in a non-embedded culvert with flow velocity less than the design target for culvert fish passage design purposes. Overall, the results of the study confirm that, embedding a CSP culvert may be an effective way to improve fish passage conditions in terms of both flow velocity and turbulence intensity.

Results are reported from full-scale testing of a buried, deep-corrugated, large-span box culvert with a 2.4 m rise and 10.0 m span under controlled laboratory conditions. A total of twenty-one experiments were conducted on the structure, measuring its response without backfill, during backfilling, under a loaded tandem axle dump truck, and under simulated vehicle loading with force applied by an actuator. Surface strain measurements were used to calculate bending moments and thrusts, while deflections were monitored using an electronic theodolite. Tests conducted to a maximum force of truck loading specified by the Canadian Highway Bridge Design Code multiplied by a dynamic load allowance factor were performed at three cover depths. The maximum moment increased from 6 to 41 kNm/m as the cover was reduced from 1.5 to 0.45 m. This was attributed to less load distribution and decreased soil-structure system stiffness at shallower cover. The maximum bending moments were consistently observed directly beneath the applied force. Tests were also conducted at forces larger than the design values to identify the ultimate limit state(s) of the structure. An ultimate limit state was encountered at approximately 800 kN where the geotechnical resistance beneath the loading pads was exceeded. A subsequent test with the loading pad force spread over larger areas permitted larger forces to be applied. An ultimate limit state of the structure involving the formation of three plastic hinges occurred at 1100 kN. The plastic hinge initially formed at the crown, followed by hinges located at each shoulder. Post-test observations showed evidence of local buckling of the conduit wall, gaps between the plates at the seams, the tilting of bolts along the longitudinal seams, and surface cracks in the soil. Applying the material resistance factor of 0.9 to the ultimate load limit of 1100 kN measured for the structure yields a reserve capacity of 1.7 when compared to the fully factored load including dynamic load allowance and live load factors. / Thesis (Master, Civil Engineering) -- Queen's University, 2008-12-23 11:56:12.314

No description available.

An investigation was performed for live load forces applied to soil-steel structures under shallow backfill depths, specifically a long span deeply corrugated box culvert. The work was also relevant to other types of flexible buried structures and loading scenarios. The investigation involved the application of both a robust experimental testing process and the development of 3-D finite element models. Full scale live load tests, performed in Dorchester NB, were executed to obtain a large sample of experimental data. The testing program was designed specifically to fully characterize the structural response of a long span box culvert to CHBDC design truck live loads. The program included live load testing at six different backfill depths with 21 unique truck positions per lift, with instrumentation at four separate rings. The experimental data was used to assess and calibrate the finite element models being developed to predict structural effects. The finite element software package ADINA was used to model the test structure in 3-D. The basics of model development, such as element types, boundary conditions, loads, and other analysis options were discussed. An orthotropic shell modeling approach to accurately describe the corrugated plate properties was developed. A number of soil constitutive models, both linear and nonlinear, were examined and evaluated. The data obtained from experimental testing was compared to the results obtained by the finite element modeling and the various soil models were evaluated. A parametric study was performed examining the sensitivity of modeling parameters. The impact of various assumptions made regarding the model was quantitatively established. The thesis provided guidance on the 3-D modeling of soil-steel structures allowing future researchers to study the factors which were significant to their design and field applications.

No description available.

Traditional culvert designs, in many cases, have become habitat barriers to aquatic animal species. In response, environmentally sensitive culvert designs have been developed to function as ecological bridges. Bottomless and buried invert culverts are examples of such designs and are commonly used for fish passage. Additional design guidance specific to streambed stability in buried-invert or bottomless culverts under high flow events is needed. This study investigated incipient motion conditions for four substrate materials in a 2-ft (0.61-m) diameter circular bottomless arch culvert and in a 1-ft (0.30-m) wide rectangular flume in a laboratory setting. General scour of the streambed within the bottomless arch culvert was also investigated under partially pressurized and non-pressurized flow conditions. This thesis discusses the experimental methods used to determine incipient motion conditions and analyses of incipient motion prediction methods. This thesis also presents the experimental results obtained from both test facilities with the results of other published incipient motion studies on gravel streambeds. Finally, the prediction efficiency of eight stone sizing methods (open channel and culvert application) applied to the experimental results was analyzed, which may be useful for determining stable stone diameters to be used as riprap in simulated streambeds through bottomless culverts.

The hydraulic analysis of culverts is complicated when using hand calculations. Fortunately, several computer programs are available to assist in analyzing culvert hydraulics, some of which include HY-8, Fish X-ing, Broken-back Culvert Analysis Program (BCAP), Hydraflow Express, Culvert Master, Culvert, and Hydrologic Engineering Center River Analysis System (HEC-RAS). While all of these programs can simulate the behavior of flow through a culvert, slightly different methodologies are utilized among the programs to complete a full hydraulic analysis, resulting in different predictions for headwater depth, flow control, and outlet velocities. The purpose of this paper is to compare (1) the available hydraulic features and (2) the numerical solutions from the seven programs to manually computed values. Four test cases were developed to test the accuracy of program results. The headwater depths and outlet velocities were compared to those obtained through calculations based on culvert hydraulic theory outlined in the Federal Highway Administration publication, Hydraulic Design Series 5. Based on the results, Fish X-ing was unable to analyze culverts under inlet control, while Culvert incorrectly predicted inlet control headwater depths at low flow conditions. Hydraflow Express struggled to predict correct outlet control headwater depths while BCAP had difficulty analyzing straight barrel culverts acting under outlet control. Overall, HY-8, Culvert Master, and HEC-RAS produced accurate results most consistently.