中国岩溶
中國巖溶
중국암용
CARSOLOGICA SINICA
2015年
1期
79-85
,共7页
李肖南%阎长虹%许宝田%段成龙%周殷康
李肖南%閻長虹%許寶田%段成龍%週慇康
리초남%염장홍%허보전%단성룡%주은강
埋藏型岩溶%跨孔地震CT%溶洞%充填物来源%持力层
埋藏型巖溶%跨孔地震CT%溶洞%充填物來源%持力層
매장형암용%과공지진CT%용동%충전물래원%지력층
burial karst%cross-hole seismic CT method%karst cave%sources of fillings%bearing layer
研究埋藏型岩溶的发育特征和充填物来源对拟建超高层建筑的选址及持力层的选择具有重要意义。本文通过跨孔地震 CT 对溶洞和破碎带进行探测,并对部分代表性溶洞的充填物进行比重试验、颗粒分析和X 射线衍射分析,结合现场工程地质情况,研究了距地表以下80余米处岩溶的规模、分布情况、岩溶发育特征及溶洞充填物来源。结果表明:溶洞发育规模较小,面积多在2 m2以下,在垂直方向具有多层性;溶洞充填率达到92.7%,多为硬塑泥质全充填,承载力较大,可作为基础持力层;溶洞填充物的矿物成分基本相同,且与上覆基岩一致,充填物来源主要为上覆基岩的剥蚀;溶洞之间不存在大的连通通道,且地下水位已降至场地溶洞以下,故该处溶洞不会进一步发育,不会对上部地基稳定性造成威胁。
研究埋藏型巖溶的髮育特徵和充填物來源對擬建超高層建築的選阯及持力層的選擇具有重要意義。本文通過跨孔地震 CT 對溶洞和破碎帶進行探測,併對部分代錶性溶洞的充填物進行比重試驗、顆粒分析和X 射線衍射分析,結閤現場工程地質情況,研究瞭距地錶以下80餘米處巖溶的規模、分佈情況、巖溶髮育特徵及溶洞充填物來源。結果錶明:溶洞髮育規模較小,麵積多在2 m2以下,在垂直方嚮具有多層性;溶洞充填率達到92.7%,多為硬塑泥質全充填,承載力較大,可作為基礎持力層;溶洞填充物的礦物成分基本相同,且與上覆基巖一緻,充填物來源主要為上覆基巖的剝蝕;溶洞之間不存在大的連通通道,且地下水位已降至場地溶洞以下,故該處溶洞不會進一步髮育,不會對上部地基穩定性造成威脅。
연구매장형암용적발육특정화충전물래원대의건초고층건축적선지급지력층적선택구유중요의의。본문통과과공지진 CT 대용동화파쇄대진행탐측,병대부분대표성용동적충전물진행비중시험、과립분석화X 사선연사분석,결합현장공정지질정황,연구료거지표이하80여미처암용적규모、분포정황、암용발육특정급용동충전물래원。결과표명:용동발육규모교소,면적다재2 m2이하,재수직방향구유다층성;용동충전솔체도92.7%,다위경소니질전충전,승재력교대,가작위기출지력층;용동전충물적광물성분기본상동,차여상복기암일치,충전물래원주요위상복기암적박식;용동지간불존재대적련통통도,차지하수위이강지장지용동이하,고해처용동불회진일보발육,불회대상부지기은정성조성위협。
The development characteristics of burial karst and sources of the karst fillings are very important for choosing the location of super-high buildings and bearing strata.This study employed the cross-hole seis-mic CT method to detect the caves and fracture zones of a foundation in Wuxi,and made indoor tests on sam-ples of the karst fillings from the typical karst caves.Combined with the in-situ geological conditions,this paper presents a qualitative analysis of the scale,distribution and development characteristics of the karst and the sources of fillings which are more than 80 meters below the foundation.The results show that the karst is of a small size,the area of most caves is less than 2 m2 ,and there are many layers in the vertical direction. The rate of cave filling reaches 92.7%,and the caves are mostly filled with hard plastic mud which has a large bearing capacity and can be used as the bearing layer of foundation.XRD analysis of mineral composi-tion shows that the minerals of different cave fillings are generally the same,consistent with those of the o-verlying bedrock.Thus,the denudation of overlying bedrock is the main source of these fillings.There is no large connective channel between the caves,and the underground water level has dropped below the caves.It is therefore concluded that these caves will not further develop and pose no threat to the stability of the foun-dation.The results of this study will provide reference for the site selection,design and construction of su-per-high buildings,karst detection,stability analysis of foundations and the treatment of unfavorable geolog-ical bodies in the Suzhou-Wuxi-Changzhou areas,which are located on deep karst foundation.