塑膠製儲水箱工程特性之尺度效應

近年來因全球暖化效應，使的全球極端氣候發生頻繁，造成世界都會區發生洪澇及淹水現象頻傳。為了解決城市的水問題近年來開始有人提出「海綿城市」的概念及低衝擊開發(Low-impact development，LID)，這兩項可有效的減緩洪澇及淹水事件減少。然海綿城市及低衝擊開發(Low-impact development，LID)裡面提到使-用雨水貯留箱(塑膠製儲水箱)可達到水再生利用，現正在推廣使用。在世界各先進國家已推行多年，日本有詳細建立完好測試機制；包括抗壓試驗、潛變試驗及往復抗剪試驗，因塑膠製儲水箱長期埋設於地底下會承受土壓力，另台灣位於地震帶所以要測試塑膠製儲水箱是不是能在往復中具有消能及抗剪的行為。本研究參考了日本社團法人雨水貯留浸透技術協會編定塑膠製雨水地下貯留滲透設施技術手冊，並協助研訂台灣下水道協會修訂了台灣測試標準，也針對這三個試驗法進行了解，並以塑膠製儲水箱的尺寸對於抗壓試驗、長期壓潛變、往復抗剪試驗及阻尼係數之影響。從抗壓試驗結果顯示，隨著試件高度愈高，其抗壓強度愈低，對於1.0m及1.5mm的高度，抗壓強度的差異非常有限，因此，以下試驗高度皆以1.0m進行抗壓試驗。Type-A和Type-B其抗壓強度為410.27kPa和107.98kPa。對於最大2.0m覆土條件，塑膠製儲水箱均可提供3.0以上的上部載重之安全係數。從長期壓潛變結果顯示，Type-A以兩種不同組合尺寸進行長期壓潛變，其垂直荷載為36kPa。尺寸為垂直向0.5*0.5*1.0m及1.0*1.0*1.0m。兩種條件下1至1000小時的垂直潛變應變約為1.90mm，潛應變對數時間曲線彼此相似。Type-B以垂直向1.0*1.0*1.0m進行長期壓潛變，其垂直荷載為36kPa，在1至1000小時的垂直潛變應變約為13.15mm。對於Type-A和Type-B塑膠製儲水箱進行了多組不同尺寸組合往復抗剪試驗，1.5*2.0*2.0m最大剪應力為8.51kPa和-8.87kPa其阻尼係數為0.114。1.5*1.5*2.0m最大剪應力為8.01kPa和-9.30kPa其阻尼係數為0.108。AV324最大剪應力為8.03kPa和-7-54kPa其阻尼係數為0.120，以上為Type-A試件。1.0*2.0*2.0m最大剪應力為11.17kPa和-11.92kPa其阻尼係數為0.197。1.5*2.0*2.0m最大剪應力為11.59kPa和-12.04kPa其阻尼係數為0.145。1.5*1.5*2.0m最大剪應力為11.36kPa和-11.10kPa其阻尼係數為0.156。1.5*1.0*2.0m最大剪應力為9.63kPa和-10.40kPa其阻尼係數為0.150，以上為Type-B試件。因此Type-B比Type-A在這兩種不同類別表現出更好的性能。

關鍵字

地下儲水箱；儲水；低影響開發； LID ；海綿城市；水回用；土工合成材料；聚烯烴

並列摘要

Underground water storage system is a useful and important LID best management practice for urban design. This system can be used to enhance water infiltration and reuse the recycled water. A series of vertical compression tests, the vertical compression creep test, and the cyclic shear test were conducted to evaluate the performance of two types of plastic storage systems. The compression strength, compression creep strain, the maximum shear resistance and damping coefficient size effects were evaluated for the tested products. The compression test results indicated that the ultimate compression strength decreases as the sample height increased. The compression strength of Type A and Type B products were 412 kPa and 108 kPa, respectively. For the typical maximum 2.0 meters overburden condition, both plastic underground storage systems can provide more than 3.0 safety factor of surcharge loading. The vertical creep deformation from 1 to 1000 hours for Type A product of two different size samples under 36 kPa vertical compression load were all about 1.9 mm and the creep strains versus log time curves were quite similar for all test conditions. Type B product were all about 13.15 mm.A series cyclic direct shear tests were conducted for both Type A and Type B products. The test sample heights and widths were all 2000mm and 1500mm. The results of the test indicated that the sample depth has no influence on the damping coefficient for both products. The damping coefficients were about 0.10 and 0.15 for Type A and Type B product. However, the shear resistance will increase as sample depth increased. The shear resistance of Type A and Type B products varied from 7.54 kPa to 9.30 kPa and from 9.63 kPa to 12.04 kPa, respectively. The shear resistance and damping coefficient of Type B product were slightly better than that for the type A product.

並列關鍵字

Underground storage tank ； Water storage ； Low-impact development ； LID ； Sponge city ； Water reuse ； Geosynthetic ； Polyolefin

參考文獻

1. ASTM D5262, 2002. “Standard Test Method for Evaluating the Unconfined Tension Creep Behavior of Geosynthetics,” American Society for Testing and Materials, West Conshohocken, PA

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2. ASTM D7406, 2007. “Standard Test Method for Time-Dependent (Creep) Deformation Under Constant Pressure for Geosynthetic Drainage Products,” American Society for Testing and Materials, West Conshohocken, PA

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3. ASTM D6364, 2006. “Standard Test Method for Determining Short-Term Compression Behavior of Geosynthetics,” American Society for Testing and Materials, West Conshohocken, PA

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4. ASTM D2412, 2011. “Standard Test Method for Determination of External Loading Characteristics of Plastic Pipe by Parallel-Plate Loading,” American Society for Testing and Materials, West Conshohocken, PA

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5. JIS K 7181，2011，Plastics-Determination of compressive properties。

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