JP4310597B2

JP4310597B2 - Tank roof

Info

Publication number: JP4310597B2
Application number: JP2000091971A
Authority: JP
Inventors: 宏治石井; 勇奥積
Original assignee: 株式会社石井鐵工所
Priority date: 2000-03-29
Filing date: 2000-03-29
Publication date: 2009-08-12
Anticipated expiration: 2020-03-29
Also published as: JP2001279946A

Description

【０００１】
【発明の属する技術分野】
この発明は、潅漑用水や水道水等の液体、或いは穀物や石炭等の粉粒体、若しくは廃棄物のごみ等の貯蔵物を常圧下で貯蔵する大形貯槽に設ける貯槽屋根に関するものである。
【０００２】
【従来の技術】
潅漑用水や水道水等の液体、或いは穀物や石炭等の粉粒体、若しくは廃棄物のごみ等の貯蔵物を常圧下で貯蔵する大形貯槽の屋根は、例えば鋼製底壁と鋼製側壁よりなる貯槽本体の、その鋼製側壁の上部に鋼製屋根骨を配設し、その屋根骨の上に鋼板製の屋根板を敷き並べ溶接結合して形成した円錐形状またはドーム形状等の鋼製屋根、あるいはコンクリート製底壁とコンクリート製側壁よりなる貯槽本体の、そのコンクリート製側壁の上部に、支保工に支えられた型枠を設け、その型枠上に鉄筋を配設しコンクリートを流し込み、あるいは吹き付け等して形成した円錐形状あるいはドーム形状等のコンクリート製屋根が用いられている。
【０００３】
また、その他の屋根として、内部の空気圧を外部の空気圧より高めにし、その空気圧の差で膜体を支えたエアドーム屋根、或は本出願人に係る特許第２６０８４７４号のコンクリート製屋根、つまり貯槽本体内部の昇圧空気圧を受けた張力状態の可撓膜体上にコンクリート等を設置して形成するコンクリート製ドーム屋根も普及している。
【０００４】
【発明が解決しようとする課題】
上記第１番目従来技術の鋼製屋根は、堅牢で優れた構造の屋根ではあるが、屋根部品の工場製作等に多くの手間がかかり、その屋根の現場構築には多くの技能工を必要とする。また、上記第２番目従来技術のコンクリート製屋根は、上記鋼製屋根と同様に、堅牢で優れた構造の屋根ではあるが、支保工等の仮設に多くの費用がかかり、型枠の製作作業等には高度の熟練工を必要とする。
【０００５】
上記第３番目従来技術のエアドーム屋根は、簡便な構造で大形野球場等の屋根にも適したものではあるが、台風等による強風や気圧変化に対する心配が残るもので、内部の昇圧空気圧管理にも常に細心の注意を必要とする。それらに対し、特許第２６０８４７４号のコンクリート製ドーム屋根は、仮設費用が少なく、多くの熟練工も必要とせず、かつ安全に構築できる優れたドーム形状の屋根ではあるが、屋根に降る雨水を一箇所に集めて排水可能で、かつデザイン的にも優れた懸垂線曲線形状、つまりカテナリー形状を呈した屋根ではなかった。
【０００６】
この発明は上述従来技術の屋根が内在する問題等の課題を解決するためになされたもので、仮設費用が少なく、かつ多くの熟練工も必要とせず、さらに、中央部を安定させ作業能率良く、短い工期で、より安全に構築できるとともに、中央部が一体化し均一で形状に優れ、高い強度を備えた大形カテナリー形状の貯槽屋根を提供するものである。
【０００７】
【課題を解決するための手段】
この発明に係る貯槽屋根は、底壁と側壁とよりなる貯槽本体の該側壁上部に端縁を固定しカテナリー状に掛け渡して緊張材を設け、該緊張材の上に設け上記貯槽本体を被覆する可撓膜体は、該可撓膜体の中央部を貫通して上方に突出する筒状部材からなる溢流ノズルを設けてなり、該可撓膜体をカテナリー状の緊張状態下で、該可撓膜体の上面に設置する被覆強度材を剛体化せしめて形成し、さらに、上記溢流ノズルの周囲には、該溢流ノズルの高さより高い堰板を、上記可撓膜体及び前記被覆強度材と一体化するように立設し、該堰板の上部を被覆するろ過器を設け、さらに、上記形成した貯槽屋根上に突出する溢流ノズルの上端縁に蓋状弁を設け、かつ該蓋状弁は浮力で開き重力で閉じるようにフロートを設け、さらに、上記形成した貯槽屋根上に突出する溢流ノズルの下端部に排水管を設け、該排水管は貯槽の気層部を通って貯槽外部に至るように形成したものである。
【００１０】
【発明の実施の形態】
図１乃至図４に基づいて、この発明に係る貯槽屋根の実施形態例について説明する。図１は、潅漑用水を貯蔵するコンクリート製の貯槽屋根に、この発明に係る貯槽屋根を適用した実施形態例で、図２は、この貯槽屋根を一部切り欠いて示す斜視説明図である。図３は、溢流ノズルの上端縁にフロート付き蓋状弁を設けて形成した貯槽屋根を示す実施形態例であり、図４は、溢流ノズルの下端部から貯槽外部へ至る排水管を設けて形成した貯槽屋根を示す実施形態例である。
【００１１】
図１に示すように、貯槽本体１は、平版状のコンクリート製底壁２と、この底壁２の外周縁近傍部に直立する円筒形のコンクリート製側壁３と、この側壁３の上端部に周縁を結合したカテナリー形状の貯槽屋根４とで形成する。このカテナリー形状の貯槽屋根４は、図２に一部を切り欠いて示すように、貯槽本体１の側壁３の上部に緊張材１０の端縁を固定してカテナリー状に掛け渡し、その緊張材１０の上に、周縁を側壁３の上部に気密固定した可撓膜体５を設け、次いで、排気装置（図示省略）を用いて貯槽内を減圧し可撓膜体５をカテナリー状の緊張状態にして、この可撓膜体５の上面に、設置後剛体化するコンクリートモルタル等の被覆強度材６を設けて剛体化せしめ、上記貯槽内の減圧を解除して形成するものである。
【００１２】
このカテナリー形に設ける可撓膜体５は、該可撓膜体５の中央部を上下に貫通し上方に突出する筒状部材７を予め設けておいて、該筒状部材７は貯槽屋根４の中央部を貫通して上部に突出する溢流ノズル８に形成する。なお、溢流ノズル８の上部を被覆する夾雑物ろ過器９を設置した場合には、夾雑物１１は分離され雨水１２のみが貯槽内へと排水される。
【００１３】
図２に基づいて、可撓膜体５についてさらに詳述する。可撓膜体５は、その中央部を貫通して筒状部材７を設ける。この筒状部材７は、可撓膜体５の貫通する開口部周縁を補強するように、テンション性能に優れた金属製円筒、或いは合成樹脂製円筒などのセンターリングに形成し、可撓膜体５に接着や溶着、或いは取付部材などを介して気密で強固に一体結合しておく。なお、この筒状部材７の上端部には吊り係合部１３などを設け、図の二点鎖線で示すように、可撓膜体５を貯槽上部に吊り上げて搬入し、該可撓膜体５の周縁を側壁３上部に気密固定する際に使用する。
【００１４】
上記のように筒状部材７を設けた可撓膜体５は、膜材の貫通部周縁近傍に補強膜を当てて溶着したり或いは周縁を括って環状に纏めて筒状部材７と結合することによって、中央の開口部周縁の強度が向上する。また、図の二点鎖線で示すように、筒状部材７上端縁の吊り係合部１３にワイヤを係合し、可撓膜体５を吊り上げて貯槽の中心上方に移動する際に、筒状部材７周縁結合部全体でその荷重を分散するので、可撓膜体５の周縁部に無理な力がかかることなく損傷などの心配がない。また、可撓膜体５の中心の位置決めがし易く、中央にかかる張力を筒状部材７で平均に受け、均一な力で引っ張ることができるので、可撓膜体５周縁を側壁３上部に固定設置する際の作業性が良い。なお、緊張材１０を放射状に設けその中央部を筒状部材７の下端部に接続した場合には、筒状部材７を中心にして緊張材１０に平均に張力がかかるため、緊張材１０の中央部の重心が安定し均一な形状が得られる。そして、可撓膜体５を側壁３周縁に気密固定した後には、この筒状部材７の開口部に、図の網線で示す遮閉蓋１４を設けて閉塞し、次いで気密固定した可撓膜体５下部の貯槽内を減圧してカテナリー状に張設する。この減圧して張設する際にも、筒状部材７によって可撓膜体５の中央部の重心が安定するため、均一で美観に優れたカテナリー形状を得ることができる。
【００１５】
次いで、上記カテナリー状に緊張させた状態の可撓膜体５の上面に、設置後剛体化する被覆強度材６を設ける。この際に筒状部材７の外周部は、被覆強度材６内の鉄筋など（図示省略）に溶接或いは接合部材などを介して一体に結合する。次いで、被覆強度材６が剛体化した後、貯槽本体１内の減圧を解除して、カテナリー状を呈した貯槽屋根４を形成する。この減圧解除の際に、減圧によってカテナリー形状の緊張状態を呈していた可撓膜体５、およびこの可撓膜体５に抑えられて下方にカテナリー形状の緊張状態を呈していた緊張材１０が、中央の筒状部材７を中心にして平均に浮き上がり元のカテナリー形状に復元しようとして、剛体化した被覆強度材６に下方から上方に向けて押上げ力を加える。そして、その押上げ力が付勢することによって、緊張材１０と可撓膜体５と被覆強度材６の一体化剛性力は増し、さらに屋根中央の筒状部材７との一体化によって屋根中央部の結合力が一層向上する。この一体化し結合力の向上した貯槽屋根４は、上記押上げ力にも助けられて、貯槽屋根４の上に加わる荷重、例えば積雪荷重や滞留雨水荷重などの外部荷重に強い、優れた強度を備えたカテナリー形状の貯槽屋根４となる。
【００１６】
上記貯槽屋根４の形成に用いる可撓膜体５に設けた筒状部材７は、図１に示すように、上記遮閉蓋１４を取り除いて閉塞を開放し、突出した筒状部材７そのまま、或いは筒状部材７上部に配管材等を継ぎ足し、さらに外周部を被覆強度材６とも結合し、その上端縁を貯槽屋根４の上に突出させ溢流ノズル８に形成する。このように、可撓膜体５と一体化している筒状部材７を、溢流ノズル８の全体或いは一部の部材として使用することにより、可撓膜体５と溢流ノズル８及び被覆強度材６の一体化が図られ、かつ溢流ノズル８周縁部の強度が高くなって貯槽屋根４中央部の耐久性が向上する。
【００１７】
上記貯槽屋根４に形成する溢流ノズル８は、水より比重の大きい土砂などの夾雑物１１をせき止め沈降させるように、例えば数センチメートル乃至数十センチメートル程度の突出高さとして、金属製材料、コンクリート製材料、或いは合成樹脂製材料などよりなる管材や板材、或いはパネル材などを用いて形成する。また、上記溢流ノズル８の上部を被覆する夾雑物ろ過器９は、金属製材料又は合成樹脂材料などよりなる網体を使用し、落葉やゴミなどの粗大な夾雑物１１を通過させないように、例えば数ミリメートル程度の網目間隔として、さらに、夾雑物１１を周囲に落ち易くするように、補強枠材などを用いて中央部を盛り上げ、その外周縁を溢流ノズル８の上端部に固着形成する。
【００１８】
上記のように、貯槽屋根４の中央部に突出する溢流ノズル８を設けたので、貯槽屋根４上に降る雨水１２は、中央部に集まり一旦溢流ノズル８にせき止められて、水より比重の大きい土砂などの夾雑物１１を沈降分離した後、溢流ノズル８を越えて貯槽内部へと自然流下によって流入する。また、上記溢流ノズル８の上部を被覆する夾雑物ろ過器９を設けた場合には、風や雨水１２などによって貯槽屋根４上の中央部に集まる落葉などの粗大な夾雑物１１は、夾雑物ろ過器９に遮られて貯槽内部へ侵入することがない。よって、雨水１２を貯槽屋根４上に滞留させることなく貯槽内部へ簡単容易に排水することができ、また夾雑物１１の侵入による貯蔵物の汚染もなく清浄を維持することができる。
【００１９】
そして、上記せき止める溢流ノズル８の突出高さを高くすることによって、水より比重の大きい土砂などの夾雑物１１は沈降させ充分に分離させ、また、被覆する夾雑物ろ過器９全体の表面積を広くし、中央部を盛り上げ傾斜を与えるなどして、落葉やゴミなどの粗大な夾雑物１１を周囲に落ち易くし、目詰まりや上部への堆積をなくすことによって、雨水量が多い場合でも排水が間に合わなくことはない。また、貯槽屋根４上の落葉や土砂などの夾雑物１１の除去や掃除などのメンテナンスは、中央部に掻き集めた状態で簡単容易に行える。
【００２０】
図３は、溢流ノズル８の上端縁にフロート１６付き蓋状弁１５を設けて形成した貯槽屋根４を一部欠徐して示す実施形態例である。カテナリー形状の貯槽屋根４の中央部を貫通する溢流ノズル８の上端縁に蓋状弁１５を設け、この蓋状弁１５は、浮力で開きかつ重力で閉じるように、蓋状弁１５の周囲に浮力体のフロート１６を設ける。さらに、上記溢流ノズル８の周囲には、該溢流ノズル８の高さより高い堰板１７を、可撓膜体５及び被覆強度材６と一体化するように立設し、この堰板１７の上部を被覆する金網などの夾雑物ろ過器９を、例えば山形コーン状に傾斜させて設ける。
【００２１】
上記溢流ノズル８の上端縁に設ける蓋状弁１５は、金属製材料又は合成樹脂材料よりなる平板材、或いはブロック材などを使用して蓋状に形成する。なお、この蓋状弁１５下面の溢流ノズル８との接触部端縁に、合成ゴムなどのパッキンなどを設けた場合には、上記重力による密着のシール性が良くなる。また、蓋状弁１５の周囲に設けるフロート１６は、合成樹脂材、合成ゴム材よりなるブロック体、或いは合成樹脂材、ステンレス材などを用いた中空体などを使用して浮力体に形成する。
【００２２】
このように形成した場合には、雨水１２が堰板１７を越えて侵入し、堰板１７と溢流ノズル８に囲まれた内側に溜った時に、雨水１２から受ける浮力でフロート１６が浮上して蓋状弁１５を平均に開口させ、雨水１２は溢流ノズル８の上端部から貯槽内へと流入する。雨水１２の量が少ない時や降雨がない通常使用時にはフロート１６及び蓋状弁１５は、その重力で水平を保ち平均に押圧して、溢流ノズル８の上端部を閉塞する。また、雨水１２や風などとともに屋根４の中央に集まってくる水より比重の大きい土砂など１１ｂは、堰板１７によってせき止められ沈降して堆積し、落葉など水に浮く粗大物１１ａは夾雑物ろ過器９によって遮られる。このように落葉や土砂などの夾雑物１１が堰板１７及び夾雑物ろ過器９から侵入しないので、その内部に位置するフロート１６及び蓋状弁１５は、夾雑物１１の介在による作動障害を受けることなく安全確実に作動する。
【００２３】
上記のように、屋根４上の雨水１２は中央部に集まり堰板１７を越え夾雑物ろ過器９を通過してフロート１６を浮上させ、フロート１６の浮力で蓋状弁１５を開口させるため、溢流ノズル８から安全確実に雨水１２を貯槽内部へ排出することができる。なお、雨水１２が排出された後などの通常使用時には、蓋状弁１５はフロート１６及び蓋状弁１５の重力によって溢流ノズル８を閉塞するので、貯槽内のガスは蒸発して大気中に流出することがない。
【００２４】
図４は、溢流ノズル８の下端部に貯槽外部へ至る排水管１８を設けて形成した貯槽屋根４を一部欠徐して示す実施形態例である。カテナリー形状の貯槽屋根４の中央部を貫通する溢流ノズル８から貯槽の気層部を通って貯槽外部に至るように、該溢流ノズル８の下端部に排水管１８を設け、さらに、この溢流ノズル８の周囲に堰板１７を立設し、その上部を被覆する金網などの夾雑物ろ過器９を、例えばドーム状に傾斜させて設けたものである。
【００２５】
この排水管１８には、特別な弁体などを取付ける必要はなく、例えば、硬質塩化ビニル管、ポリエチレン管、ライニング鋼管などの耐食性を有する軽量な管材を使用する。なお、排水管１８の接続部１９は、溢流ノズル８を上部から差し込む構造、或いはねじ込む構造などの着脱容易な接続構造とした場合には、貯槽屋根４の上部から点検や掃除などを行うメンテナンス作業が容易となる。
【００２６】
上記のように形成した場合には、貯槽屋根４上の中央部に集まった雨水１２は、溢流ノズル８から排水管１８内を重力によって自然に流下し、貯槽外部へと排出除去される。また、夾雑物１１は、堰板１７及び夾雑物ろ過器９に遮断されて、排水管１８内部へ侵入することがなく詰まりも生じない。そして、貯槽内のベーパーやガスも大気中へ放出されることがない。
【００２７】
このように雨水１２は排水管１８によってタンク外部へ排出されるため、貯蔵物が雨水１２の侵入によって汚染され品質低下することがない。また、排水管１８は、貯蔵物内を通過していないので、貯蔵物が排水管１８の通過によって汚れることなく、貯蔵物が排水管１８内へ侵入することもないので雨水１２との混合の心配も生じない。よって、雨水１２の混入が好ましくない上水道水、油等の液体、或いは穀物や石炭等の粉粒体、若しくは乾燥ごみ等の貯蔵物などを貯蔵する大形貯槽の貯槽屋根４に設ける排水構造に適したものとなる。
【００２８】
なお、図１乃至図４の実施形態例は、貯槽屋根がコンクリート構造の場合について示したが、コンクリート以外の金属や合成樹脂などの構成部材で形成した大形カテナリー形状の貯槽屋根においても、上記と同様に適用することができる。
【００２９】
【発明の効果】
上述の説明で明らかなように、この発明に係る貯槽屋根は、側壁上部に端縁を固定しカテナリー状に掛け渡して緊張材を設け、該緊張材の上に設け貯槽本体を被覆する可撓膜体は中央部を貫通して上方に突出する筒状部材からなる溢流ノズルを設けてなり、該可撓膜体をカテナリー状の緊張状態下で、該可撓膜体の上面に設置する被覆強度材を剛体化せしめて形成したので、上記筒状部材を設けた可撓膜体中央部の強度が向上し、また、この筒状部材を使用した可撓膜体の吊り上げ及び取付けは作業性が良く、可撓膜体中央部が安定し平均に張設され、可撓膜体と被覆強度材と溢流ノズルとの一体化が向上し美観に優れたカテナリー形状となる。よって、仮設費用が少なく、かつ多くの熟練工も必要とせず、さらに作業能率良く短い工期で、より安全に構築できるとともに、形状に優れ高い強度を備えた大形カテナリー形状の貯槽屋根とすることができる。さらに、溢流ノズルの周囲には、該溢流ノズルの高さより高い堰板を、可撓膜体及び被覆強度材と一体化するように立設し、この堰板の上部を被覆する金網などの夾雑物ろ過器を設けたので、雨水や風などとともに屋根の中央に集まってくる水より比重の大きい土砂などは、堰板によってせき止められ沈降して堆積し、落葉など水に浮く粗大物は夾雑物ろ過器によって遮られ、その内部に位置するフロート及び蓋状弁は、夾雑物の介在による作動障害を受けることなく安全確実に作動する。
【００３０】
また、上記溢流ノズルの上端縁に蓋状弁を設け、かつ該蓋状弁は浮力で開き重力で閉じるようにフロートを設けて形成した貯槽屋根にあっては、屋根上の中央部に溜った雨水でフロートを浮上させ、その浮力で蓋状弁を開口させるため、雨水を確実容易に貯槽内部へ排出することができる。そして、雨水が排出された後の通常使用状態の蓋状弁は、フロート及び蓋状弁の重力によって閉塞されるので、貯槽内ガスと大気の出入りがないため、貯槽内を気密に保持した貯槽屋根となる。また、貯槽屋根の中央部に集まる落葉や土砂などの夾雑物は、突出した溢流ノズルによって遮られるため、フロート及び蓋状弁に作動障害を与えることがなく、貯槽内へ夾雑物が侵入することもなく貯蔵物を清浄な状態に維持する貯槽屋根となる。
【００３１】
また、上記溢流ノズルの下端部に排水管を設け、該排水管は貯槽の気層部を通って貯槽外部に至るように形成した貯槽屋根にあっては、貯蔵物が雨水の侵入によって汚染されることはなく、この排水管は、貯蔵物内を通過していないので、貯蔵物が排水管の通過によって汚れることなく、また貯蔵物が排水管内へ侵入することもない。このように、雨水と貯蔵物との混合の心配がないので、雨水との混合が好ましくない上水道等の液体、或いは穀物等の粉粒体などの貯蔵物を貯蔵する貯槽屋根に適したものとなる。
【００３２】
【図面の簡単な説明】
【図１】この発明に係る貯槽屋根の一実施形態例を一部簡略化して示す縦断面説明図である。
【図２】図１の貯槽屋根を一部切り欠いて示す斜視説明図である。
【図３】溢流ノズルの上端縁にフロート付き蓋状弁を設けた貯槽屋根を一部欠除して示した側断面説明図である。
【図４】溢流ノズルの下端部から貯槽外部へ至る排水管を設けた貯槽屋根を一部欠除して示した側断面説明図である。
【符号の説明】
１貯槽本体２底壁３側壁
４貯槽屋根５可撓膜体６被覆強度材
７筒状部材８溢流ノズル９夾雑物ろ過器
１０緊張材１１夾雑物１１ａ粗大物
１１ｂ土砂など１２雨水１３吊り係合部
１４遮閉蓋１５蓋状弁１６フロート
１７堰板１８排水管１９接続部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a storage tank roof provided in a large storage tank that stores liquids such as irrigation water and tap water, or granular materials such as grains and coal, or wastes such as waste waste under normal pressure.
[0002]
[Prior art]
The roof of a large storage tank that stores liquids such as irrigation water and tap water, or granular materials such as grains and coal, or waste waste, etc. under normal pressure is, for example, a steel bottom wall and a steel side wall. Conical or dome-shaped steel formed by placing a steel roof bone on the upper part of the steel side wall of the storage tank body, placing a steel plate roof plate on the roof bone, and welding together On the top of the concrete side wall of the storage tank body consisting of a roof made of concrete or a concrete bottom wall and a concrete side wall, a formwork supported by a support is provided, and reinforcing bars are placed on the formwork to pour the concrete. Alternatively, a concrete roof having a conical shape or a dome shape formed by spraying or the like is used.
[0003]
Further, as another roof, an air dome roof in which the internal air pressure is made higher than the external air pressure and the film body is supported by the difference in air pressure, or the concrete roof of the patent No. 2608474 related to the present applicant, that is, the storage tank body A concrete dome roof formed by installing concrete or the like on a flexible film body in a tension state subjected to internal pressurized air pressure is also widespread.
[0004]
[Problems to be solved by the invention]
The steel roof of the first prior art is a robust and excellent structure roof, but it takes a lot of labor to produce the roof parts in the factory and requires many technicians to construct the roof site. To do. In addition, the second prior art concrete roof, like the steel roof, is a robust and excellent roof, but requires a lot of temporary work such as support work, and the production work of the formwork. Etc. require highly skilled workers.
[0005]
The third conventional air dome roof has a simple structure and is suitable for large baseball stadium roofs, but there is still concern over strong winds and changes in atmospheric pressure due to typhoons, etc. Even always need great care. On the other hand, the concrete dome roof of Japanese Patent No. 2608474 is an excellent dome-shaped roof that can be constructed safely without requiring a lot of skilled work, and has only one place of rainwater that falls on the roof. It was not a roof with a catenary shape that could be collected and drained, and had an excellent design.
[0006]
This invention was made in order to solve the problems such as the problems inherent in the above-described prior art roof, has a low temporary cost, does not require many skilled workers, and further stabilizes the central portion with good work efficiency. It is intended to provide a large catenary-shaped storage tank roof that can be constructed more safely in a short construction period, and has a uniform central portion, uniform shape, and high strength.
[0007]
[Means for Solving the Problems]
The storage tank roof according to the present invention is provided with a tension material by fixing an edge to the upper portion of the side wall of the storage tank main body composed of a bottom wall and a side wall and extending in a catenary form, and is provided on the tension material to cover the storage tank main body. The flexible membrane body is provided with an overflow nozzle made of a cylindrical member that protrudes upward through the central portion of the flexible membrane body, and the flexible membrane body is under catenary tension, A covering strength material to be installed on the upper surface of the flexible membrane body is made rigid, and a dam plate higher than the height of the overflow nozzle is provided around the overflow nozzle, and the flexible membrane body and The filter is installed upright so as to be integrated with the covering strength material, and covers the upper part of the weir plate. Further, a lid-like valve is provided at the upper edge of the overflow nozzle protruding on the storage tank roof. The lid-like valve is provided with a float so as to open with buoyancy and close with gravity, and further to the storage formed above. The drainage pipe to the lower end of the overflow nozzle projecting on the roof provided, drainage pipe is obtained by so as to extend in the reservoir out through the air layer portion of the reservoir.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Based on FIG. 1 thru | or FIG. 4, the example of embodiment of the storage tank roof which concerns on this invention is demonstrated. FIG. 1 is an example of an embodiment in which a storage tank roof according to the present invention is applied to a concrete storage tank roof for storing irrigation water, and FIG. 2 is a perspective explanatory view showing a part of the storage tank roof. FIG. 3 is an embodiment showing a storage tank roof formed by providing a lid-like valve with a float at the upper edge of the overflow nozzle, and FIG. 4 shows a drain pipe extending from the lower end of the overflow nozzle to the outside of the storage tank. It is the example of an embodiment which shows the storage tank roof formed in this way.
[0011]
As shown in FIG. 1, the storage tank body 1 includes a lithographic concrete bottom wall 2, a cylindrical concrete side wall 3 standing upright in the vicinity of the outer peripheral edge of the bottom wall 2, and an upper end portion of the side wall 3. It is formed with a catenary-shaped storage tank roof 4 having peripheral edges combined. As shown in FIG. 2, the catenary-shaped storage tank roof 4 is stretched in a catenary shape by fixing the edge of the tension material 10 to the upper part of the side wall 3 of the storage tank body 1. A flexible membrane body 5 having a peripheral edge hermetically fixed to the upper portion of the side wall 3 is provided on 10, and then the inside of the storage tank is depressurized using an exhaust device (not shown) so that the flexible membrane body 5 is in a catenary tension state. Then, a coating strength material 6 such as concrete mortar that becomes rigid after installation is provided on the upper surface of the flexible film body 5 to make it rigid, and the reduced pressure in the storage tank is released.
[0012]
The flexible membrane body 5 provided in this catenary shape is provided with a cylindrical member 7 that penetrates the central portion of the flexible membrane body 5 in the vertical direction and protrudes upward. The overflow nozzle 8 is formed so as to penetrate through the center of the nozzle and protrude upward. In addition, when the contaminant filter 9 which coat | covers the upper part of the overflow nozzle 8 is installed, the contaminant 11 is isolate | separated and only the rainwater 12 is drained into a storage tank.
[0013]
Based on FIG. 2, the flexible film body 5 will be further described in detail. The flexible film body 5 is provided with a cylindrical member 7 penetrating through the central portion thereof. The cylindrical member 7 is formed on a center ring such as a metal cylinder or a synthetic resin cylinder excellent in tension performance so as to reinforce the peripheral edge of the opening through which the flexible film body 5 penetrates. 5 is bonded tightly and tightly in an airtight manner through adhesion, welding, or an attachment member. The tubular member 7 is provided with a suspension engaging portion 13 and the like at the upper end portion, and as shown by a two-dot chain line in the figure, the flexible film body 5 is lifted and carried over the storage tank, and the flexible film body 5 is used when airtightly fixing the periphery of 5 to the upper part of the side wall 3.
[0014]
The flexible film body 5 provided with the cylindrical member 7 as described above is welded by applying a reinforcing film to the vicinity of the periphery of the penetrating portion of the membrane material, or joined to the cylindrical member 7 by concentrating the periphery in an annular shape. This improves the strength of the peripheral edge of the central opening. Further, as shown by a two-dot chain line in the figure, when the wire is engaged with the suspension engaging portion 13 at the upper end edge of the cylindrical member 7 and the flexible film body 5 is lifted and moved upward in the center of the storage tank, the cylinder Since the load is distributed over the entire peripheral joint portion of the shaped member 7, an excessive force is not applied to the peripheral portion of the flexible film body 5, and there is no fear of damage or the like. Further, since the center of the flexible film body 5 is easily positioned, and the tension applied to the center is averaged by the cylindrical member 7 and can be pulled with a uniform force, the periphery of the flexible film body 5 is placed on the upper side of the side wall 3. Good workability for fixed installation. In addition, when the tension material 10 is provided radially and the central portion thereof is connected to the lower end portion of the cylindrical member 7, the tension material 10 is averagely tensioned around the cylindrical member 7. The center of gravity at the center is stable and a uniform shape is obtained. After the flexible membrane 5 is hermetically fixed to the periphery of the side wall 3, the opening of the cylindrical member 7 is closed by providing a shielding lid 14 indicated by a mesh line in the figure, and then the flexible film is hermetically fixed. The inside of the storage tank below the film body 5 is decompressed and stretched in a catenary manner. Even when this tension is applied under reduced pressure, the cylindrical member 7 stabilizes the center of gravity of the central portion of the flexible film body 5, so that a catenary shape that is uniform and excellent in appearance can be obtained.
[0015]
Next, a covering strength material 6 that is rigid after installation is provided on the upper surface of the flexible film body 5 in a tensioned state in the catenary form. At this time, the outer peripheral portion of the cylindrical member 7 is integrally coupled to a reinforcing bar or the like (not shown) in the covering strength material 6 through welding or a joining member. Next, after the covering strength material 6 becomes rigid, the decompression in the storage tank body 1 is released, and the storage tank roof 4 having a catenary shape is formed. When the decompression is released, the flexible film body 5 that has been in a catenary shape due to the decompression, and the tension material 10 that has been restrained by the flexible film body 5 and has exhibited a catenary shape in a downward direction are provided. Then, a push-up force is applied from the bottom upward to the rigid coating strength member 6 in an attempt to restore to the original catenary shape that floats on the average around the central cylindrical member 7. When the pushing-up force is energized, the integrated rigidity of the tension material 10, the flexible membrane body 5, and the covering strength material 6 is increased, and further, the center of the roof is integrated with the tubular member 7 at the center of the roof. The joint strength of the part is further improved. The integrated storage tank roof 4 with improved bonding force is also strong against external loads such as a snow load and a stagnant rainwater load applied to the storage tank roof 4 with the help of the lifting force. The catenary-shaped storage tank roof 4 is provided.
[0016]
As shown in FIG. 1, the cylindrical member 7 provided on the flexible membrane body 5 used for forming the storage tank roof 4 opens the blockage by removing the blocking lid 14, and the protruding cylindrical member 7 is left as it is. Alternatively, a pipe member or the like is added to the upper part of the tubular member 7, and the outer peripheral part is also coupled to the covering strength member 6, and the upper end edge thereof protrudes above the storage tank roof 4 to form the overflow nozzle 8. Thus, by using the cylindrical member 7 integrated with the flexible film body 5 as a whole or a part of the overflow nozzle 8, the flexible film body 5, the overflow nozzle 8, and the covering strength. The material 6 is integrated, and the strength of the peripheral portion of the overflow nozzle 8 is increased, so that the durability of the central portion of the storage tank roof 4 is improved.
[0017]
The overflow nozzle 8 formed on the storage tank roof 4 has a protruding height of, for example, about several centimeters to several tens of centimeters so as to prevent sediment 11 such as earth and sand having a specific gravity greater than that of water. It is formed using a tube material, a plate material, a panel material, or the like made of concrete material, synthetic resin material, or the like. The foreign matter filter 9 covering the upper part of the overflow nozzle 8 uses a net made of a metal material or a synthetic resin material so as not to pass coarse impurities 11 such as fallen leaves and dust. For example, as a mesh interval of about several millimeters, the central portion is raised using a reinforcing frame member so that the foreign matter 11 can easily fall to the periphery, and the outer peripheral edge thereof is fixed to the upper end portion of the overflow nozzle 8. To do.
[0018]
As described above, since the overflow nozzle 8 protruding in the central portion of the storage tank roof 4 is provided, the rainwater 12 falling on the storage tank roof 4 gathers in the central portion and is once dammed up by the overflow nozzle 8 to have a specific gravity from the water. After the sediment 11 such as large sediment is settled and separated, it flows into the storage tank through the overflow nozzle 8 by natural flow. In addition, when the foreign matter filter 9 covering the upper part of the overflow nozzle 8 is provided, coarse foreign matter 11 such as fallen leaves gathered at the central part on the storage tank roof 4 by wind or rainwater 12 is contaminated. It is not blocked by the material filter 9 and enters the storage tank. Therefore, the rainwater 12 can be easily drained into the storage tank without staying on the storage tank roof 4, and the cleanliness can be maintained without contamination of the storage product due to the intrusion of the impurities 11.
[0019]
Then, by increasing the protruding height of the overflow nozzle 8 to prevent the sediment 11 such as earth and sand having a specific gravity larger than that of water, the sediment 11 is sufficiently separated and the surface area of the entire dust filter 9 to be coated is reduced. Drain even when there is a lot of rainwater by increasing the width of the center and adding a slope to make coarse impurities 11 such as fallen leaves and garbage easy to fall around, eliminating clogging and accumulation on top. Can't miss it. In addition, maintenance such as removal and cleaning of foreign substances 11 such as fallen leaves and earth and sand on the storage tank roof 4 can be easily and easily performed in a state of being collected in the central portion.
[0020]
FIG. 3 shows an embodiment in which a part of the storage tank roof 4 formed by providing a lid-like valve 15 with a float 16 at the upper end edge of the overflow nozzle 8 is shown. A lid-like valve 15 is provided at the upper edge of the overflow nozzle 8 that passes through the central portion of the catenary-shaped storage tank roof 4, and this lid-like valve 15 is arranged around the lid-like valve 15 so as to open by buoyancy and close by gravity. The float 16 of the buoyancy body is provided in Further, a dam plate 17 higher than the height of the overflow nozzle 8 is provided around the overflow nozzle 8 so as to be integrated with the flexible film body 5 and the covering strength material 6. A foreign matter filter 9 such as a wire mesh covering the upper part of the wire is provided so as to be inclined in a chevron cone shape, for example.
[0021]
The lid-like valve 15 provided at the upper end edge of the overflow nozzle 8 is formed in a lid shape using a flat plate material or a block material made of a metal material or a synthetic resin material. In addition, when packing such as synthetic rubber is provided at the edge of the contact portion between the lower surface of the lid-like valve 15 and the overflow nozzle 8, the sealing performance for adhesion due to gravity is improved. The float 16 provided around the lid-like valve 15 is formed into a buoyancy body using a block body made of a synthetic resin material, a synthetic rubber material, or a hollow body made of a synthetic resin material, a stainless steel material, or the like.
[0022]
In this case, when the rainwater 12 enters beyond the dam plate 17 and accumulates inside the dam plate 17 and the overflow nozzle 8, the float 16 floats by the buoyancy received from the rainwater 12. Thus, the lid-like valve 15 is opened to the average, and the rainwater 12 flows into the storage tank from the upper end portion of the overflow nozzle 8. When the amount of rain water 12 is small or during normal use when there is no rainfall, the float 16 and the lid-like valve 15 are leveled by the gravity and pressed to the average to close the upper end portion of the overflow nozzle 8. In addition, earth and sand 11b having a specific gravity larger than the water gathered in the center of the roof 4 together with rain water 12 and wind is dammed and sedimented by the dam plate 17, and coarse matter 11a floating on the water such as fallen leaves is filtered by impurities. Blocked by vessel 9. In this way, the foreign matter 11 such as fallen leaves and earth and sand does not enter from the weir plate 17 and the foreign matter filter 9, so that the float 16 and the lid-like valve 15 located in the interior receive an operation failure due to the presence of the foreign matter 11. It operates safely and reliably.
[0023]
As described above, the rainwater 12 on the roof 4 gathers at the center, passes through the weir plate 17 and passes through the contaminant filter 9 to float the float 16, and opens the lid valve 15 by the buoyancy of the float 16. The rainwater 12 can be discharged from the overflow nozzle 8 safely and reliably into the storage tank. During normal use, such as after the rainwater 12 is discharged, the lid valve 15 closes the overflow nozzle 8 due to the gravity of the float 16 and the lid valve 15, so that the gas in the storage tank evaporates into the atmosphere. There is no leakage.
[0024]
FIG. 4 shows an embodiment in which a part of the storage tank roof 4 formed by providing a drain pipe 18 extending to the outside of the storage tank at the lower end of the overflow nozzle 8 is shown. A drain pipe 18 is provided at the lower end of the overflow nozzle 8 from the overflow nozzle 8 penetrating the central portion of the catenary-shaped storage tank roof 4 to the outside of the storage tank through the gas layer of the storage tank. A dam plate 17 is erected around the overflow nozzle 8 and a foreign matter filter 9 such as a wire mesh covering the upper portion thereof is provided so as to be inclined in a dome shape, for example.
[0025]
It is not necessary to attach a special valve body or the like to the drain pipe 18. For example, a lightweight pipe material having corrosion resistance such as a hard vinyl chloride pipe, a polyethylene pipe, or a lining steel pipe is used. In addition, when the connection part 19 of the drain pipe 18 is made into an easily attachable / detachable connection structure such as a structure in which the overflow nozzle 8 is inserted from the top or a structure in which the overflow nozzle 8 is screwed in, maintenance is performed such as inspection or cleaning from the top of the storage tank roof 4. Work becomes easy.
[0026]
When formed as described above, the rainwater 12 collected at the central portion on the storage tank roof 4 naturally flows down from the overflow nozzle 8 through the drain pipe 18 by gravity, and is discharged and removed outside the storage tank. Further, the contaminant 11 is blocked by the barrier plate 17 and the contaminant filter 9 and does not enter the drain pipe 18 and is not clogged. Further, neither vapor nor gas in the storage tank is released into the atmosphere.
[0027]
As described above, since the rainwater 12 is discharged to the outside of the tank by the drain pipe 18, the stored matter is not contaminated by the intrusion of the rainwater 12 and the quality is not deteriorated. Further, since the drain pipe 18 does not pass through the stored product, the stored product is not contaminated by the passage of the drain tube 18, and the stored product does not enter the drain tube 18. No worries. Therefore, in the drainage structure provided in the storage tank roof 4 of a large storage tank for storing water such as tap water, oil, etc., which is not preferably mixed with rainwater 12, or granular materials such as grains or coal, or storage such as dry waste It will be suitable.
[0028]
In addition, although the example of embodiment of FIG. 1 thru | or FIG. 4 showed about the case where a storage tank roof is a concrete structure, also in the large-sized catenary-shaped storage tank roof formed with structural members, such as metals other than concrete and synthetic resins, it is the above-mentioned. Can be applied as well.
[0029]
【The invention's effect】
As apparent from the above description above, the reservoir roof according to the invention, by passing over the fixed end edges to the side wall upper catenary shape provided tendon, covers the reservoir body provided on the tension member variable The flexible membrane body is provided with an overflow nozzle made of a cylindrical member that penetrates through the center and protrudes upward, and the flexible membrane body is placed on the upper surface of the flexible membrane body under a catenary tension state. Since the covering strength material to be formed is made rigid, the strength of the central portion of the flexible film body provided with the cylindrical member is improved, and the lifting and mounting of the flexible film body using the cylindrical member is The workability is good, the central portion of the flexible film body is stably and uniformly stretched, the integration of the flexible film body, the covering strength material, and the overflow nozzle is improved, and the catenary shape is excellent in aesthetics. Therefore, it is possible to construct a large catenary-shaped storage tank roof that has low temporary costs, does not require many skilled workers, can be constructed more safely with a short work period with high work efficiency, and has excellent shape and high strength. it can. Further, a dam plate higher than the height of the overflow nozzle is erected around the overflow nozzle so as to be integrated with the flexible film body and the covering strength material, and a wire mesh covering the upper portion of the dam plate. The soil filter, which has a greater specific gravity than the water gathered in the center of the roof along with rainwater and wind, is dammed and deposited by the weir plate. The float and the lid-like valve which are blocked by the foreign matter filter and located inside thereof operate safely and reliably without being subjected to an operation failure due to the presence of foreign matter.
[0030]
In addition, in the case of a storage tank roof provided with a lid valve on the upper edge of the overflow nozzle, and the lid valve is formed so as to open by buoyancy and close by gravity, it accumulates at the center of the roof. Since the float is floated by the rainwater and the lid valve is opened by the buoyancy, the rainwater can be discharged into the storage tank easily and reliably. Since the lid-like valve in the normal use state after the rainwater is discharged is closed by the gravity of the float and the lid-like valve, there is no entry and exit of gas and air in the storage tank, so that the storage tank is kept airtight. It becomes the roof. In addition, since foreign matters such as fallen leaves and earth and sand gathered in the central part of the storage tank roof are blocked by the protruding overflow nozzle, the foreign substances enter the storage tank without causing an operation failure to the float and the lid valve. It becomes a storage tank roof that keeps the stored items clean.
[0031]
In addition, a drainage pipe is provided at the lower end of the overflow nozzle, and the drainage pipe is stored in the storage tank roof formed so as to pass through the gas layer of the storage tank and reach the outside of the storage tank. Since the drain pipe does not pass through the stored product, the stored product is not contaminated by the passage of the drain tube, and the stored product does not enter the drain tube. In this way, since there is no concern about mixing rainwater with stored items, it is suitable for storage tank roofs that store stored products such as liquids such as waterworks or grains such as grains that are not preferable to mix with rainwater. Become.
[0032]
[Brief description of the drawings]
FIG. 1 is a longitudinal cross-sectional explanatory view showing a part of an embodiment of a storage tank roof according to the present invention in a simplified manner.
FIG. 2 is a perspective explanatory view showing the storage tank roof of FIG. 1 with a part cut away.
FIG. 3 is an explanatory side sectional view showing a part of a storage tank roof provided with a lid-like valve with a float at the upper end edge of an overflow nozzle.
FIG. 4 is a side cross-sectional explanatory view showing a part of a storage tank roof provided with a drain pipe extending from the lower end of the overflow nozzle to the outside of the storage tank.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Storage tank body 2 Bottom wall 3 Side wall 4 Storage tank roof 5 Flexible film body 6 Covering strength material 7 Cylindrical member 8 Overflow nozzle 9 Contaminant filter 10 Tensile material 11 Contaminant 11a Coarse material 11b Sediment etc. 12 Rainwater 13 Suspension Joint part 14 Shielding lid 15 Lid valve 16 Float 17 Dam plate 18 Drain pipe 19 Connection part

Claims

A flexible membrane body covering the storage tank body provided on the tension material by fixing an edge to the upper portion of the side wall of the storage tank body composed of a bottom wall and a side wall and laying it in a catenary shape. An overflow nozzle made of a cylindrical member that protrudes upward through the center of the flexible membrane body is provided, and the flexible membrane body is placed on the upper surface of the flexible membrane body in a catenary-like tension state. Formed by stiffening the covering strength material to be installed ,
Further, a dam plate higher than the height of the overflow nozzle is provided around the overflow nozzle so as to be integrated with the flexible film body and the covering strength material, and covers the upper portion of the dam plate. Provided with a filter
Furthermore, a lid-like valve is provided at the upper edge of the overflow nozzle protruding on the storage tank roof formed above, and the lid-like valve is provided with a float so as to open by buoyancy and close by gravity,
Furthermore, a drainage pipe is provided at the lower end portion of the overflow nozzle projecting on the storage tank roof formed above, and the drainage pipe is formed so as to reach the outside of the storage tank through the gas layer portion of the storage tank. .