福永街道2016年地质灾害治理工程-白石厦
社区昌荣有限电机厂南山体边坡工程
主 动 防 护 网 施 工 方 案
编 制 人: 审 核 人: 审 批 人: 编制单位:化工部郑州地质工程勘察院 审批日期:二O一七年七月二十日
福永街道2016年地质灾害治理工程-白石厦社区昌荣有限电机厂南山体边坡 主动防护网施工方案 目 录
一、工程概况 ···················································································· 3 二、编制依据 ···················································································· 3 三、工程措施 ···················································································· 4 四、施工工艺 ···················································································· 4 五、施工方法 ···················································································· 7
1、测量放线 ················································································ 7
2、人工清理坡面浮土及浮石、搭设施工脚手架 ·································· 7 3、测量放线确定锚杆孔、钻孔并清孔 ·············································· 7 4、安装锚杆并注浆 ······································································· 7 7、铺设高强度钢绳菱形网并缝合 ····················································· 8 8、预应力加固 ············································································· 8 六、施工进度安排 ·············································································· 8 七、资源配置 ···················································································· 8
1、劳动力配置 ············································································· 8 2、主要施工机械设备配置 ······························································ 8 3、主要材料供应 ·········································································· 9 八、交通安全、保通措施 ····································································· 9 九、质量保证措施 ············································································ 10 十、安全生产措施 ············································································ 10 十一、环境保护措施 ········································································· 11
福永街道2016年地质灾害治理工程-白石厦社区昌荣有限电机厂南山体边坡 主动防护网施工方案 SNS主动防护网施工技术方案
一、工程概况
本项目是宝安区政府2016年重点民生工程,该边坡原始地貌类型为低丘陵斜坡地形,后经人工开挖坡体、切割坡脚形成的现有边坡形态,该坡类型为岩质边坡,该边坡较高,主要由微风化花岗岩组成,但由于受局部构造、爆破裂隙和岩土体组合控制影响等影响可能发生垮塌等地质灾害对坡脚建筑及人员构成严重威胁,因此该边坡该边坡存在严重地质灾害安全隐患,需进行地质灾害综合治理工作。根据边坡所处地质环境条件,结合边坡以往所做工作,岩质边坡治理措施为:清除危岩及碎石+锚杆+主动防护网+排水,强风化边坡治理措施为:锚杆格构+排水绿化的措施进行边坡崩塌地质灾害的治理。
本合同段山体极为陡峭,其危岩、落石及岩体分化剥落比较发育,采用人工清除松动的岩体后挂设主动网进行支护,处治面积共计27410m2。 二、编制依据
1、 深圳市勘察研究院有限公司的《福永街道2016年地质灾害治理工程-白石厦社区昌荣有限电机厂南山体边坡边坡勘查报告、施工设计图》;
2、国家及广东省、深圳市有关部委颁发的相关法律、法规、规范性文件、标准、规范(程)包括
《中华人民共和国建筑法》 《中华人民共和国安全生产法》
《建筑边坡工程技术规范》(GB50330-2013) 《岩土锚杆(索)技术规程》(CECS22-2005) 《砌体结构设计规范》(GB50003-2011) 《建筑地基基础设计规范》(GB50007-2011) 《混凝土结构设计规范》(GB50010-2010)
福永街道2016年地质灾害治理工程-白石厦社区昌荣有限电机厂南山体边坡 主动防护网施工方案 《边坡生态防护指南》(SZDB/Z 31-2010) 《深圳经济特区建设项目环境保护条例》 3、探勘现场所了解的现场具体情况; 4、我司现有施工力量和技术装备情况; 5、我司在其它类似工程的施工中取得的经验; 6、《建设工程施工合同》。
5、现场实际施工地形、地质、电力及通讯杆线分布等情况。 三、工程措施
本系统说明的是SNS主动防护网系统,其采用带锚垫板的预应力钢筋锚杆将专用高强度格栅张紧固定覆盖于边坡上,适用于具有溜坍、崩塌、浅层滑动、风化剥落、危岩落石等潜在地质灾害的土质或岩石边坡加固和防护。
(2)主要构成
格栅:由高强度防腐钢丝编制,菱形网孔内切圆直径65mm,网块标准规格TC/30/65/10×3.5m;
锚杆:一般采用一端(外露段)带加工螺纹的Φ25普通螺纹钢筋锚杆,并进行热镀锌防腐处理;成孔困难时可采用自进式中空锚杆;
锚垫板:菱形钢板,四个角带有弯钩,尺寸不小于350×170mm,厚度不小于8mm;需要时可改变或简化其结构;
边界绳:地形边界复杂时或需提高边界封闭效果时考虑选用,φ16热镀锌钢绳,单根长度不宜大于40m,每根两端各配一根长度为2~3m的2φ16双股钢丝绳锚杆;
辅助锚杆:用于在局部低凹或边界处使格栅更好地紧贴坡面,构成与主要锚杆相同,但直径可约小,一般为20~25mm,长度一般选用1~1.5m;
打入式锚钉:用于边坡局部低凹或边界处使格栅更好地紧贴坡面,宜用Φ16钢筋,长度一般为0.3~0.6m,一端焊接弯钩;
福永街道2016年地质灾害治理工程-白石厦社区昌荣有限电机厂南山体边坡 主动防护网施工方案 (3)设计参数与材料配置及要求
防护区域:一般应向既有或潜在破坏区外延伸至少1m以上;
锚杆间距a和b:2~4m,本支护间距为a=2.5m;b=2.0m;由于边坡可能存在局部破碎区域,在该区域内应采取加强措施,可适当加密锚杆的间距与长度,视破碎区域的具体情况而定;
预应力P:存在区域性滑动失稳时按30~50kN设计,仅防护风化剥落或落石时拧紧螺母使格栅尽可能紧贴坡面即可;
锚杆长度L:微风化岩中锚杆长度3m(外露段长度10~18cm),宜锚入滑动边界以下1m以上,并保证抗拔力不低于40kN或1.3P;
锚杆直径D:一般为28mm,保证单根杆体抗破断拉力不低于100kN或3P; 锚杆倾角:一般宜近于垂直坡面,当格栅有悬空时,宜使锚杆与张紧后的格栅表面近于垂直;
锚杆孔:一般应干钻,孔径应比锚杆直径大12mm以上;
格栅:①需用材料面积=1.05~1.08×拟防护面积,就近取为整数张格栅的面积,现场可根据需要进行纵向分割;②钢丝格栅不应有明显机械损伤和锈蚀现象,其端头应至少扭结一次,扭结处不应有裂纹;③钢丝格栅编织用钢丝应符合“GB/T 343-1994”的规定,热镀锌等级不低于AB级;
缝合钢丝或钢丝绳:网块间的纵向接长采用与格栅编织用同型号钢丝加工的波纹缝合丝缝合或直接缝合,网块间的横向连接采用φ8热镀锌钢丝绳或与格栅编织用同型号钢丝,长度约为缝合路径直线长度的1.2倍;
锚垫板:数量与锚杆根数相同,并带专用螺母; (4)施工顺序(A)与方法
①清坡:规整地形边界,清除浮土浮石,需要时回填凹坑,砍伐无特殊保留价值的树木至根部;
②以坡脚为基准线放线布置锚杆孔位,宜设于天然凹坑处,但间距不应大于设计值的10%;
③在不具备能使格栅紧贴坡面的天然凹坑的孔位处开凿孔口凹坑;